Refactor progress handling (#2549)

Previously it was Backend's responsibility to store the last progress,
and when calling routines in Collection, one had to construct and pass
in a Fn, which wasn't the most ergonomic. This PR adds the last progress
state to the collection, so that the routines no longer need a separate
progress arg, and makes some other tweaks to improve ergonomics.

ThrottlingProgressHandler has been tweaked so that it now stores the
current state, so that callers don't need to store it separately. When
a long-running routine starts, it calls col.new_progress_handler(),
which automatically initializes the data to defaults, and updates the
shared UI state, so we no longer need to manually update the state at
the start of an operation.

The backend shares the Arc<Mutex<>> with the collection, so it can get
at the current state, and so we can update the state when importing a
backup.

Other tweaks:

- The current Incrementor was awkward to use in the media check, which
uses a single incrementing value across multiple method calls, so I've
added a simpler alternative for such cases. The old incrementor method
has been kept, but implemented directly on ThrottlingProgressHandler.
- The full sync code was passing the progress handler in a complicated
way that may once have been required, but no longer is.
- On the Qt side, timers are now stopped before deletion, or they keep
running for a few seconds.
- I left the ChangeTracker using a closure, as it's used for both importing
and syncing.

qt/aqt/mediacheck.py

@@ -59,6 +59,7 @@ class MediaChecker:
 
     def _set_progress_enabled(self, enabled: bool) -> None:
         if self._progress_timer:
+            self._progress_timer.stop()
             self._progress_timer.deleteLater()
             self._progress_timer = None
         if enabled:

qt/aqt/mediasync.py

@@ -78,6 +78,7 @@ class MediaSyncer:
     def _on_finished(self, future: Future) -> None:
         self._syncing = False
         if self._progress_timer:
+            self._progress_timer.stop()
             self._progress_timer.deleteLater()
             self._progress_timer = None
         gui_hooks.media_sync_did_start_or_stop(False)

qt/aqt/progress.py

@@ -236,6 +236,7 @@ class ProgressManager:
                 self._show_timer.stop()
                 self._show_timer = None
         if self._backend_timer:
+            self._backend_timer.stop()
             self._backend_timer.deleteLater()
             self._backend_timer = None
 

rslib/src/backend/collection.rs

@@ -7,11 +7,10 @@ pub(super) use anki_proto::collection::collection_service::Service as Collection
 use anki_proto::generic;
 use tracing::error;
 
-use super::progress::Progress;
 use super::Backend;
-use crate::backend::progress::progress_to_proto;
 use crate::collection::CollectionBuilder;
 use crate::prelude::*;
+use crate::progress::progress_to_proto;
 use crate::storage::SchemaVersion;
 
 impl CollectionService for Backend {
@@ -38,7 +37,8 @@ impl CollectionService for Backend {
             .set_force_schema11(input.force_schema11)
             .set_media_paths(input.media_folder_path, input.media_db_path)
             .set_server(self.server)
-            .set_tr(self.tr.clone());
+            .set_tr(self.tr.clone())
+            .set_shared_progress_state(self.progress_state.clone());
 
         *guard = Some(builder.build()?);
 
@@ -70,15 +70,10 @@ impl CollectionService for Backend {
         &self,
         _input: generic::Empty,
     ) -> Result<anki_proto::collection::CheckDatabaseResponse> {
-        let mut handler = self.new_progress_handler();
-        let progress_fn = move |progress, throttle| {
-            handler.update(Progress::DatabaseCheck(progress), throttle);
-        };
         self.with_col(|col| {
-            col.check_database(progress_fn).map(|problems| {
+            col.check_database()
-                anki_proto::collection::CheckDatabaseResponse {
+                .map(|problems| anki_proto::collection::CheckDatabaseResponse {
                     problems: problems.to_i18n_strings(&col.tr),
-                }
                 })
         })
     }

rslib/src/backend/import_export.rs

@@ -8,11 +8,8 @@ use anki_proto::import_export::export_limit;
 pub(super) use anki_proto::import_export::importexport_service::Service as ImportExportService;
 use anki_proto::import_export::ExportLimit;
 
-use super::progress::Progress;
 use super::Backend;
 use crate::import_export::package::import_colpkg;
-use crate::import_export::ExportProgress;
-use crate::import_export::ImportProgress;
 use crate::import_export::NoteLog;
 use crate::prelude::*;
 use crate::search::SearchNode;
@@ -30,12 +27,7 @@ impl ImportExportService for Backend {
 
         let col_inner = guard.take().unwrap();
         col_inner
-            .export_colpkg(
+            .export_colpkg(input.out_path, input.include_media, input.legacy)
-                input.out_path,
-                input.include_media,
-                input.legacy,
-                self.export_progress_fn(),
-            )
             .map(Into::into)
     }
 
@@ -50,7 +42,7 @@ impl ImportExportService for Backend {
             &input.col_path,
             Path::new(&input.media_folder),
             Path::new(&input.media_db),
-            self.import_progress_fn(),
+            self.new_progress_handler(),
         )
         .map(Into::into)
     }
@@ -59,7 +51,7 @@ impl ImportExportService for Backend {
         &self,
         input: anki_proto::import_export::ImportAnkiPackageRequest,
     ) -> Result<anki_proto::import_export::ImportResponse> {
-        self.with_col(|col| col.import_apkg(&input.package_path, self.import_progress_fn()))
+        self.with_col(|col| col.import_apkg(&input.package_path))
             .map(Into::into)
     }
 
@@ -75,7 +67,6 @@ impl ImportExportService for Backend {
                 input.with_media,
                 input.legacy,
                 None,
-                self.export_progress_fn(),
             )
         })
         .map(Into::into)
@@ -101,13 +92,7 @@ impl ImportExportService for Backend {
         &self,
         input: anki_proto::import_export::ImportCsvRequest,
     ) -> Result<anki_proto::import_export::ImportResponse> {
-        self.with_col(|col| {
+        self.with_col(|col| col.import_csv(&input.path, input.metadata.unwrap_or_default()))
-            col.import_csv(
-                &input.path,
-                input.metadata.unwrap_or_default(),
-                self.import_progress_fn(),
-            )
-        })
             .map(Into::into)
     }
 
@@ -115,7 +100,7 @@ impl ImportExportService for Backend {
         &self,
         input: anki_proto::import_export::ExportNoteCsvRequest,
     ) -> Result<generic::UInt32> {
-        self.with_col(|col| col.export_note_csv(input, self.export_progress_fn()))
+        self.with_col(|col| col.export_note_csv(input))
             .map(Into::into)
     }
 
@@ -128,7 +113,6 @@ impl ImportExportService for Backend {
                 &input.out_path,
                 SearchNode::from(input.limit.unwrap_or_default()),
                 input.with_html,
-                self.export_progress_fn(),
             )
         })
         .map(Into::into)
@@ -138,7 +122,7 @@ impl ImportExportService for Backend {
         &self,
         input: generic::String,
     ) -> Result<anki_proto::import_export::ImportResponse> {
-        self.with_col(|col| col.import_json_file(&input.val, self.import_progress_fn()))
+        self.with_col(|col| col.import_json_file(&input.val))
             .map(Into::into)
     }
 
@@ -146,23 +130,11 @@ impl ImportExportService for Backend {
         &self,
         input: generic::String,
     ) -> Result<anki_proto::import_export::ImportResponse> {
-        self.with_col(|col| col.import_json_string(&input.val, self.import_progress_fn()))
+        self.with_col(|col| col.import_json_string(&input.val))
             .map(Into::into)
     }
 }
 
-impl Backend {
-    fn import_progress_fn(&self) -> impl FnMut(ImportProgress, bool) -> bool {
-        let mut handler = self.new_progress_handler();
-        move |progress, throttle| handler.update(Progress::Import(progress), throttle)
-    }
-
-    fn export_progress_fn(&self) -> impl FnMut(ExportProgress, bool) -> bool {
-        let mut handler = self.new_progress_handler();
-        move |progress, throttle| handler.update(Progress::Export(progress), throttle)
-    }
-}
-
 impl From<OpOutput<NoteLog>> for anki_proto::import_export::ImportResponse {
     fn from(output: OpOutput<NoteLog>) -> Self {
         Self {

rslib/src/backend/media.rs

@@ -5,29 +5,20 @@ use anki_proto::generic;
 pub(super) use anki_proto::media::media_service::Service as MediaService;
 
 use super::notes::to_i64s;
-use super::progress::Progress;
 use super::Backend;
-use crate::media::check::MediaChecker;
 use crate::prelude::*;
 
 impl MediaService for Backend {
     type Error = AnkiError;
 
-    // media
-    //-----------------------------------------------
-
     fn check_media(&self, _input: generic::Empty) -> Result<anki_proto::media::CheckMediaResponse> {
-        let mut handler = self.new_progress_handler();
-        let progress_fn =
-            move |progress| handler.update(Progress::MediaCheck(progress as u32), true);
         self.with_col(|col| {
-            let mgr = col.media()?;
+            col.transact_no_undo(|col| {
-            col.transact_no_undo(|ctx| {
+                let mut checker = col.media_checker()?;
-                let mut checker = MediaChecker::new(ctx, &mgr, progress_fn);
                 let mut output = checker.check()?;
 
                 let mut report = checker.summarize_output(&mut output);
-                ctx.report_media_field_referencing_templates(&mut report)?;
+                col.report_media_field_referencing_templates(&mut report)?;
 
                 Ok(anki_proto::media::CheckMediaResponse {
                     unused: output.unused,
@@ -44,10 +35,7 @@ impl MediaService for Backend {
         &self,
         input: anki_proto::media::TrashMediaFilesRequest,
     ) -> Result<generic::Empty> {
-        self.with_col(|col| {
+        self.with_col(|col| col.media()?.remove_files(&input.fnames))
-            let mgr = col.media()?;
-            mgr.remove_files(&input.fnames)
-        })
             .map(Into::into)
     }
 
@@ -56,8 +44,8 @@ impl MediaService for Backend {
         input: anki_proto::media::AddMediaFileRequest,
     ) -> Result<generic::String> {
         self.with_col(|col| {
-            let mgr = col.media()?;
+            Ok(col
-            Ok(mgr
+                .media()?
                 .add_file(&input.desired_name, &input.data)?
                 .to_string()
                 .into())
@@ -65,27 +53,12 @@ impl MediaService for Backend {
     }
 
     fn empty_trash(&self, _input: generic::Empty) -> Result<generic::Empty> {
-        let mut handler = self.new_progress_handler();
+        self.with_col(|col| col.media_checker()?.empty_trash())
-        let progress_fn =
-            move |progress| handler.update(Progress::MediaCheck(progress as u32), true);
-
-        self.with_col(|col| {
-            let mgr = col.media()?;
-            let mut checker = MediaChecker::new(col, &mgr, progress_fn);
-            checker.empty_trash()
-        })
             .map(Into::into)
     }
 
     fn restore_trash(&self, _input: generic::Empty) -> Result<generic::Empty> {
-        let mut handler = self.new_progress_handler();
+        self.with_col(|col| col.media_checker()?.restore_trash())
-        let progress_fn =
-            move |progress| handler.update(Progress::MediaCheck(progress as u32), true);
-        self.with_col(|col| {
-            let mgr = col.media()?;
-            let mut checker = MediaChecker::new(col, &mgr, progress_fn);
-            checker.restore_trash()
-        })
             .map(Into::into)
     }
 }

rslib/src/backend/mod.rs

@@ -22,7 +22,6 @@ mod media;
 mod notes;
 mod notetypes;
 mod ops;
-mod progress;
 mod scheduler;
 mod search;
 mod stats;
@@ -36,7 +35,6 @@ use std::thread::JoinHandle;
 
 use anki_proto::ServiceIndex;
 use once_cell::sync::OnceCell;
-use progress::AbortHandleSlot;
 use prost::Message;
 use tokio::runtime;
 use tokio::runtime::Runtime;
@@ -55,7 +53,6 @@ use self::links::LinksService;
 use self::media::MediaService;
 use self::notes::NotesService;
 use self::notetypes::NotetypesService;
-use self::progress::ProgressState;
 use self::scheduler::SchedulerService;
 use self::search::SearchService;
 use self::stats::StatsService;
@@ -64,6 +61,10 @@ use self::sync::SyncState;
 use self::tags::TagsService;
 use crate::backend::dbproxy::db_command_bytes;
 use crate::prelude::*;
+use crate::progress::AbortHandleSlot;
+use crate::progress::Progress;
+use crate::progress::ProgressState;
+use crate::progress::ThrottlingProgressHandler;
 
 pub struct Backend {
     col: Arc<Mutex<Option<Collection>>>,
@@ -196,4 +197,13 @@ impl Backend {
     fn db_command(&self, input: &[u8]) -> Result<Vec<u8>> {
         self.with_col(|col| db_command_bytes(col, input))
     }
+
+    /// Useful for operations that function with a closed collection, such as
+    /// a colpkg import. For collection operations, you can use
+    /// [Collection::new_progress_handler] instead.
+    pub(crate) fn new_progress_handler<P: Into<Progress> + Default + Clone>(
+        &self,
+    ) -> ThrottlingProgressHandler<P> {
+        ThrottlingProgressHandler::new(self.progress_state.clone())
+    }
 }

rslib/src/backend/sync/mod.rs

@@ -13,15 +13,13 @@ use futures::future::Abortable;
 use reqwest::Url;
 use tracing::warn;
 
-use super::progress::AbortHandleSlot;
 use super::Backend;
 use crate::prelude::*;
+use crate::progress::AbortHandleSlot;
 use crate::sync::collection::normal::ClientSyncState;
-use crate::sync::collection::normal::NormalSyncProgress;
 use crate::sync::collection::normal::SyncActionRequired;
 use crate::sync::collection::normal::SyncOutput;
 use crate::sync::collection::progress::sync_abort;
-use crate::sync::collection::progress::FullSyncProgress;
 use crate::sync::collection::status::online_sync_status_check;
 use crate::sync::http_client::HttpSyncClient;
 use crate::sync::login::sync_login;
@@ -198,12 +196,13 @@ impl Backend {
         }
 
         // start the sync
-        let mgr = self.col.lock().unwrap().as_mut().unwrap().media()?;
+        let (mgr, progress) = {
-        let mut handler = self.new_progress_handler();
+            let mut col = self.col.lock().unwrap();
-        let progress_fn = move |progress| handler.update(progress, true);
+            let col = col.as_mut().unwrap();
-
+            (col.media()?, col.new_progress_handler())
+        };
         let rt = self.runtime_handle();
-        let sync_fut = mgr.sync_media(progress_fn, auth);
+        let sync_fut = mgr.sync_media(progress, auth);
         let abortable_sync = Abortable::new(sync_fut, abort_reg);
         let result = rt.block_on(abortable_sync);
 
@@ -308,12 +307,7 @@ impl Backend {
         let rt = self.runtime_handle();
 
         let ret = self.with_col(|col| {
-            let mut handler = self.new_progress_handler();
+            let sync_fut = col.normal_sync(auth.clone());
-            let progress_fn = move |progress: NormalSyncProgress, throttle: bool| {
-                handler.update(progress, throttle);
-            };
-
-            let sync_fut = col.normal_sync(auth.clone(), progress_fn);
             let abortable_sync = Abortable::new(sync_fut, abort_reg);
 
             match rt.block_on(abortable_sync) {
@@ -360,19 +354,14 @@ impl Backend {
 
         let (_guard, abort_reg) = self.sync_abort_handle()?;
 
-        let builder = col_inner.as_builder();
+        let mut builder = col_inner.as_builder();
-
-        let mut handler = self.new_progress_handler();
-        let progress_fn = Box::new(move |progress: FullSyncProgress, throttle: bool| {
-            handler.update(progress, throttle);
-        });
 
         let result = if upload {
-            let sync_fut = col_inner.full_upload(auth, progress_fn);
+            let sync_fut = col_inner.full_upload(auth);
             let abortable_sync = Abortable::new(sync_fut, abort_reg);
             rt.block_on(abortable_sync)
         } else {
-            let sync_fut = col_inner.full_download(auth, progress_fn);
+            let sync_fut = col_inner.full_download(auth);
             let abortable_sync = Abortable::new(sync_fut, abort_reg);
             rt.block_on(abortable_sync)
         };

rslib/src/collection/mod.rs

@@ -11,6 +11,7 @@ use std::fmt::Debug;
 use std::fmt::Formatter;
 use std::path::PathBuf;
 use std::sync::Arc;
+use std::sync::Mutex;
 
 use anki_i18n::I18n;
 use anki_io::create_dir_all;
@@ -21,6 +22,7 @@ use crate::decks::DeckId;
 use crate::error::Result;
 use crate::notetype::Notetype;
 use crate::notetype::NotetypeId;
+use crate::progress::ProgressState;
 use crate::scheduler::queue::CardQueues;
 use crate::scheduler::SchedulerInfo;
 use crate::storage::SchemaVersion;
@@ -39,6 +41,7 @@ pub struct CollectionBuilder {
     check_integrity: bool,
     // temporary option for AnkiDroid
     force_schema11: Option<bool>,
+    progress_handler: Option<Arc<Mutex<ProgressState>>>,
 }
 
 impl CollectionBuilder {
@@ -50,7 +53,7 @@ impl CollectionBuilder {
         builder
     }
 
-    pub fn build(&self) -> Result<Collection> {
+    pub fn build(&mut self) -> Result<Collection> {
         let col_path = self
             .collection_path
             .clone()
@@ -74,7 +77,10 @@ impl CollectionBuilder {
             media_db,
             tr,
             server,
-            state: CollectionState::default(),
+            state: CollectionState {
+                progress: self.progress_handler.clone().unwrap_or_default(),
+                ..Default::default()
+            },
         };
 
         Ok(col)
@@ -121,6 +127,13 @@ impl CollectionBuilder {
         self.check_integrity = check_integrity;
         self
     }
+
+    /// If provided, progress info will be written to the provided mutex, and
+    /// can be tracked on a separate thread.
+    pub fn set_shared_progress_state(&mut self, state: Arc<Mutex<ProgressState>>) -> &mut Self {
+        self.progress_handler = Some(state);
+        self
+    }
 }
 
 #[derive(Debug, Default)]
@@ -137,11 +150,11 @@ pub struct CollectionState {
     /// The modification time at the last backup, so we don't create multiple
     /// identical backups.
     pub(crate) last_backup_modified: Option<TimestampMillis>,
+    pub(crate) progress: Arc<Mutex<ProgressState>>,
 }
 
 pub struct Collection {
     pub storage: SqliteStorage,
-    #[allow(dead_code)]
     pub(crate) col_path: PathBuf,
     pub(crate) media_folder: PathBuf,
     pub(crate) media_db: PathBuf,

rslib/src/dbcheck.rs

@@ -21,6 +21,7 @@ use crate::notetype::Notetype;
 use crate::notetype::NotetypeId;
 use crate::notetype::NotetypeKind;
 use crate::prelude::*;
+use crate::progress::ThrottlingProgressHandler;
 use crate::timestamp::TimestampMillis;
 use crate::timestamp::TimestampSecs;
 
@@ -39,12 +40,16 @@ pub struct CheckDatabaseOutput {
     invalid_ids: usize,
 }
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, Default)]
-pub(crate) enum DatabaseCheckProgress {
+pub enum DatabaseCheckProgress {
+    #[default]
     Integrity,
     Optimize,
     Cards,
-    Notes { current: u32, total: u32 },
+    Notes {
+        current: usize,
+        total: usize,
+    },
     History,
 }
 
@@ -93,11 +98,9 @@ impl CheckDatabaseOutput {
 
 impl Collection {
     /// Check the database, returning a list of problems that were fixed.
-    pub(crate) fn check_database<F>(&mut self, mut progress_fn: F) -> Result<CheckDatabaseOutput>
+    pub(crate) fn check_database(&mut self) -> Result<CheckDatabaseOutput> {
-    where
+        let mut progress = self.new_progress_handler();
-        F: FnMut(DatabaseCheckProgress, bool),
+        progress.set(DatabaseCheckProgress::Integrity)?;
-    {
-        progress_fn(DatabaseCheckProgress::Integrity, false);
         debug!("quick check");
         if self.storage.quick_check_corrupt() {
             debug!("quick check failed");
@@ -107,21 +110,21 @@ impl Collection {
             ));
         }
 
-        progress_fn(DatabaseCheckProgress::Optimize, false);
+        progress.set(DatabaseCheckProgress::Optimize)?;
         debug!("optimize");
         self.storage.optimize()?;
 
-        self.transact_no_undo(|col| col.check_database_inner(progress_fn))
+        self.transact_no_undo(|col| col.check_database_inner(progress))
     }
 
-    fn check_database_inner<F>(&mut self, mut progress_fn: F) -> Result<CheckDatabaseOutput>
+    fn check_database_inner(
-    where
+        &mut self,
-        F: FnMut(DatabaseCheckProgress, bool),
+        mut progress: ThrottlingProgressHandler<DatabaseCheckProgress>,
-    {
+    ) -> Result<CheckDatabaseOutput> {
         let mut out = CheckDatabaseOutput::default();
 
         // cards first, as we need to be able to read them to process notes
-        progress_fn(DatabaseCheckProgress::Cards, false);
+        progress.set(DatabaseCheckProgress::Cards)?;
         debug!("check cards");
         self.check_card_properties(&mut out)?;
         self.check_orphaned_cards(&mut out)?;
@@ -131,9 +134,9 @@ impl Collection {
         self.check_filtered_cards(&mut out)?;
 
         debug!("check notetypes");
-        self.check_notetypes(&mut out, &mut progress_fn)?;
+        self.check_notetypes(&mut out, &mut progress)?;
 
-        progress_fn(DatabaseCheckProgress::History, false);
+        progress.set(DatabaseCheckProgress::History)?;
 
         debug!("check review log");
         self.check_revlog(&mut out)?;
@@ -207,14 +210,11 @@ impl Collection {
         Ok(())
     }
 
-    fn check_notetypes<F>(
+    fn check_notetypes(
         &mut self,
         out: &mut CheckDatabaseOutput,
-        mut progress_fn: F,
+        progress: &mut ThrottlingProgressHandler<DatabaseCheckProgress>,
-    ) -> Result<()>
+    ) -> Result<()> {
-    where
-        F: FnMut(DatabaseCheckProgress, bool),
-    {
         let nids_by_notetype = self.storage.all_note_ids_by_notetype()?;
         let norm = self.get_config_bool(BoolKey::NormalizeNoteText);
         let usn = self.usn()?;
@@ -225,8 +225,11 @@ impl Collection {
         self.storage.clear_all_tags()?;
 
         let total_notes = self.storage.total_notes()?;
-        let mut checked_notes = 0;
 
+        progress.set(DatabaseCheckProgress::Notes {
+            current: 0,
+            total: total_notes as usize,
+        })?;
         for (ntid, group) in &nids_by_notetype.into_iter().group_by(|tup| tup.0) {
             debug!("check notetype: {}", ntid);
             let mut group = group.peekable();
@@ -241,14 +244,10 @@ impl Collection {
 
             let mut genctx = None;
             for (_, nid) in group {
-                progress_fn(
+                progress.increment(|p| {
-                    DatabaseCheckProgress::Notes {
+                    let DatabaseCheckProgress::Notes { current, .. } = p else { unreachable!() };
-                        current: checked_notes,
+                    current
-                        total: total_notes,
+                })?;
-                    },
-                    true,
-                );
-                checked_notes += 1;
 
                 let mut note = self.get_note_fixing_invalid_utf8(nid, out)?;
                 let original = note.clone();
@@ -434,8 +433,6 @@ mod test {
     use crate::decks::DeckId;
     use crate::search::SortMode;
 
-    fn progress_fn(_progress: DatabaseCheckProgress, _throttle: bool) {}
-
     #[test]
     fn cards() -> Result<()> {
         let mut col = Collection::new();
@@ -448,7 +445,7 @@ mod test {
             .db
             .execute_batch("update cards set ivl=1.5,due=2000000,odue=1.5")?;
 
-        let out = col.check_database(progress_fn)?;
+        let out = col.check_database()?;
         assert_eq!(
             out,
             CheckDatabaseOutput {
@@ -458,12 +455,12 @@ mod test {
             }
         );
         // should be idempotent
-        assert_eq!(col.check_database(progress_fn)?, Default::default());
+        assert_eq!(col.check_database()?, Default::default());
 
         // missing deck
         col.storage.db.execute_batch("update cards set did=123")?;
 
-        let out = col.check_database(progress_fn)?;
+        let out = col.check_database()?;
         assert_eq!(
             out,
             CheckDatabaseOutput {
@@ -482,7 +479,7 @@ mod test {
 
         // missing note
         col.storage.remove_note(note.id)?;
-        let out = col.check_database(progress_fn)?;
+        let out = col.check_database()?;
         assert_eq!(
             out,
             CheckDatabaseOutput {
@@ -508,7 +505,7 @@ mod test {
         values (0,0,0,0,1.5,1.5,0,0,0)",
         )?;
 
-        let out = col.check_database(progress_fn)?;
+        let out = col.check_database()?;
         assert_eq!(
             out,
             CheckDatabaseOutput {
@@ -536,7 +533,7 @@ mod test {
         card.id.0 += 1;
         col.storage.add_card(&mut card)?;
 
-        let out = col.check_database(progress_fn)?;
+        let out = col.check_database()?;
         assert_eq!(
             out,
             CheckDatabaseOutput {
@@ -556,7 +553,7 @@ mod test {
         card.template_idx = 10;
         col.storage.add_card(&mut card)?;
 
-        let out = col.check_database(progress_fn)?;
+        let out = col.check_database()?;
         assert_eq!(
             out,
             CheckDatabaseOutput {
@@ -583,7 +580,7 @@ mod test {
         col.storage
             .db
             .execute_batch("update notes set flds = 'a\x1fb\x1fc\x1fd'")?;
-        let out = col.check_database(progress_fn)?;
+        let out = col.check_database()?;
         assert_eq!(
             out,
             CheckDatabaseOutput {
@@ -598,7 +595,7 @@ mod test {
         col.storage
             .db
             .execute_batch("update notes set flds = 'a'")?;
-        let out = col.check_database(progress_fn)?;
+        let out = col.check_database()?;
         assert_eq!(
             out,
             CheckDatabaseOutput {
@@ -626,7 +623,7 @@ mod test {
             .execute([deck.id])?;
         assert_eq!(col.storage.get_all_deck_names()?.len(), 2);
 
-        let out = col.check_database(progress_fn)?;
+        let out = col.check_database()?;
         assert_eq!(
             out,
             CheckDatabaseOutput {
@@ -657,7 +654,7 @@ mod test {
 
         col.set_tag_collapsed("one", false)?;
 
-        col.check_database(progress_fn)?;
+        col.check_database()?;
 
         assert!(col.storage.get_tag("one")?.unwrap().expanded);
         assert!(!col.storage.get_tag("two")?.unwrap().expanded);

rslib/src/import_export/gather.rs

@@ -8,10 +8,10 @@ use anki_io::filename_is_safe;
 use itertools::Itertools;
 
 use super::ExportProgress;
-use super::IncrementableProgress;
 use crate::decks::immediate_parent_name;
 use crate::latex::extract_latex;
 use crate::prelude::*;
+use crate::progress::ThrottlingProgressHandler;
 use crate::revlog::RevlogEntry;
 use crate::search::CardTableGuard;
 use crate::search::NoteTableGuard;
@@ -61,7 +61,7 @@ impl ExchangeData {
 
     pub(super) fn gather_media_names(
         &mut self,
-        progress: &mut IncrementableProgress<ExportProgress>,
+        progress: &mut ThrottlingProgressHandler<ExportProgress>,
     ) -> Result<()> {
         let mut inserter = |name: String| {
             if filename_is_safe(&name) {

rslib/src/import_export/mod.rs

@@ -6,8 +6,6 @@ mod insert;
 pub mod package;
 pub mod text;
 
-use std::marker::PhantomData;
-
 pub use anki_proto::import_export::import_response::Log as NoteLog;
 pub use anki_proto::import_export::import_response::Note as LogNote;
 use snafu::Snafu;
@@ -18,18 +16,20 @@ use crate::text::strip_html_preserving_media_filenames;
 use crate::text::truncate_to_char_boundary;
 use crate::text::CowMapping;
 
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
 pub enum ImportProgress {
-    File,
+    #[default]
     Extracting,
+    File,
     Gathering,
     Media(usize),
     MediaCheck(usize),
     Notes(usize),
 }
 
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
 pub enum ExportProgress {
+    #[default]
     File,
     Gathering,
     Notes(usize),
@@ -37,80 +37,6 @@ pub enum ExportProgress {
     Media(usize),
 }
 
-/// Wrapper around a progress function, usually passed by the
-/// [crate::backend::Backend], to make repeated calls more ergonomic.
-pub(crate) struct IncrementableProgress<P>(Box<dyn FnMut(P, bool) -> bool>);
-
-impl<P> IncrementableProgress<P> {
-    /// `progress_fn: (progress, throttle) -> should_continue`
-    pub(crate) fn new(progress_fn: impl 'static + FnMut(P, bool) -> bool) -> Self {
-        Self(Box::new(progress_fn))
-    }
-
-    /// Returns an [Incrementor] with an `increment()` function for use in
-    /// loops.
-    pub(crate) fn incrementor<'inc, 'progress: 'inc, 'map: 'inc>(
-        &'progress mut self,
-        mut count_map: impl 'map + FnMut(usize) -> P,
-    ) -> Incrementor<'inc, impl FnMut(usize) -> Result<()> + 'inc> {
-        Incrementor::new(move |u| self.update(count_map(u), true))
-    }
-
-    /// Manually triggers an update.
-    /// Returns [AnkiError::Interrupted] if the operation should be cancelled.
-    pub(crate) fn call(&mut self, progress: P) -> Result<()> {
-        self.update(progress, false)
-    }
-
-    fn update(&mut self, progress: P, throttle: bool) -> Result<()> {
-        if (self.0)(progress, throttle) {
-            Ok(())
-        } else {
-            Err(AnkiError::Interrupted)
-        }
-    }
-
-    /// Stopgap for returning a progress fn compliant with the media code.
-    pub(crate) fn media_db_fn(
-        &mut self,
-        count_map: impl 'static + Fn(usize) -> P,
-    ) -> Result<impl FnMut(usize) -> bool + '_> {
-        Ok(move |count| (self.0)(count_map(count), true))
-    }
-}
-
-pub(crate) struct Incrementor<'f, F: 'f + FnMut(usize) -> Result<()>> {
-    update_fn: F,
-    count: usize,
-    update_interval: usize,
-    _phantom: PhantomData<&'f ()>,
-}
-
-impl<'f, F: 'f + FnMut(usize) -> Result<()>> Incrementor<'f, F> {
-    fn new(update_fn: F) -> Self {
-        Self {
-            update_fn,
-            count: 0,
-            update_interval: 17,
-            _phantom: PhantomData,
-        }
-    }
-
-    /// Increments the progress counter, periodically triggering an update.
-    /// Returns [AnkiError::Interrupted] if the operation should be cancelled.
-    pub(crate) fn increment(&mut self) -> Result<()> {
-        self.count += 1;
-        if self.count % self.update_interval != 0 {
-            return Ok(());
-        }
-        (self.update_fn)(self.count)
-    }
-
-    pub(crate) fn count(&self) -> usize {
-        self.count
-    }
-}
-
 impl Note {
     pub(crate) fn into_log_note(self) -> LogNote {
         LogNote {

rslib/src/import_export/package/apkg/export.rs

@@ -16,8 +16,8 @@ use crate::import_export::package::colpkg::export::export_collection;
 use crate::import_export::package::media::MediaIter;
 use crate::import_export::package::Meta;
 use crate::import_export::ExportProgress;
-use crate::import_export::IncrementableProgress;
 use crate::prelude::*;
+use crate::progress::ThrottlingProgressHandler;
 
 impl Collection {
     /// Returns number of exported notes.
@@ -30,10 +30,8 @@ impl Collection {
         with_media: bool,
         legacy: bool,
         media_fn: Option<Box<dyn FnOnce(HashSet<String>) -> MediaIter>>,
-        progress_fn: impl 'static + FnMut(ExportProgress, bool) -> bool,
     ) -> Result<usize> {
-        let mut progress = IncrementableProgress::new(progress_fn);
+        let mut progress = self.new_progress_handler();
-        progress.call(ExportProgress::File)?;
         let temp_apkg = new_tempfile_in_parent_of(out_path.as_ref())?;
         let mut temp_col = new_tempfile()?;
         let temp_col_path = temp_col
@@ -54,7 +52,7 @@ impl Collection {
             with_media,
         )?;
 
-        progress.call(ExportProgress::File)?;
+        progress.set(ExportProgress::File)?;
         let media = if let Some(media_fn) = media_fn {
             media_fn(data.media_filenames)
         } else {
@@ -80,19 +78,19 @@ impl Collection {
         meta: &Meta,
         path: &str,
         search: impl TryIntoSearch,
-        progress: &mut IncrementableProgress<ExportProgress>,
+        progress: &mut ThrottlingProgressHandler<ExportProgress>,
         with_scheduling: bool,
         with_media: bool,
     ) -> Result<ExchangeData> {
         let mut data = ExchangeData::default();
-        progress.call(ExportProgress::Gathering)?;
+        progress.set(ExportProgress::Gathering)?;
         data.gather_data(self, search, with_scheduling)?;
         if with_media {
             data.gather_media_names(progress)?;
         }
 
         let mut temp_col = Collection::new_minimal(path)?;
-        progress.call(ExportProgress::File)?;
+        progress.set(ExportProgress::File)?;
         temp_col.insert_data(&data)?;
         temp_col.set_creation_stamp(self.storage.creation_stamp()?)?;
         temp_col.set_creation_utc_offset(data.creation_utc_offset)?;

rslib/src/import_export/package/apkg/import/media.rs

@@ -15,10 +15,10 @@ use crate::import_export::package::media::extract_media_entries;
 use crate::import_export::package::media::MediaCopier;
 use crate::import_export::package::media::SafeMediaEntry;
 use crate::import_export::ImportProgress;
-use crate::import_export::IncrementableProgress;
 use crate::media::files::add_hash_suffix_to_file_stem;
 use crate::media::files::sha1_of_reader;
 use crate::prelude::*;
+use crate::progress::ThrottlingProgressHandler;
 
 /// Map of source media files, that do not already exist in the target.
 #[derive(Default)]
@@ -76,7 +76,7 @@ fn prepare_media(
     media_entries: Vec<SafeMediaEntry>,
     archive: &mut ZipArchive<File>,
     existing_sha1s: &HashMap<String, Sha1Hash>,
-    progress: &mut IncrementableProgress<ImportProgress>,
+    progress: &mut ThrottlingProgressHandler<ImportProgress>,
 ) -> Result<MediaUseMap> {
     let mut media_map = MediaUseMap::default();
     let mut incrementor = progress.incrementor(ImportProgress::MediaCheck);

rslib/src/import_export/package/apkg/import/mod.rs

@@ -24,10 +24,10 @@ use crate::collection::CollectionBuilder;
 use crate::import_export::gather::ExchangeData;
 use crate::import_export::package::Meta;
 use crate::import_export::ImportProgress;
-use crate::import_export::IncrementableProgress;
 use crate::import_export::NoteLog;
 use crate::media::MediaManager;
 use crate::prelude::*;
+use crate::progress::ThrottlingProgressHandler;
 use crate::search::SearchNode;
 
 struct Context<'a> {
@@ -37,20 +37,17 @@ struct Context<'a> {
     meta: Meta,
     data: ExchangeData,
     usn: Usn,
-    progress: IncrementableProgress<ImportProgress>,
+    progress: ThrottlingProgressHandler<ImportProgress>,
 }
 
 impl Collection {
-    pub fn import_apkg(
+    pub fn import_apkg(&mut self, path: impl AsRef<Path>) -> Result<OpOutput<NoteLog>> {
-        &mut self,
-        path: impl AsRef<Path>,
-        progress_fn: impl 'static + FnMut(ImportProgress, bool) -> bool,
-    ) -> Result<OpOutput<NoteLog>> {
         let file = open_file(path)?;
         let archive = ZipArchive::new(file)?;
+        let progress = self.new_progress_handler();
 
         self.transact(Op::Import, |col| {
-            let mut ctx = Context::new(archive, col, progress_fn)?;
+            let mut ctx = Context::new(archive, col, progress)?;
             ctx.import()
         })
     }
@@ -60,10 +57,8 @@ impl<'a> Context<'a> {
     fn new(
         mut archive: ZipArchive<File>,
         target_col: &'a mut Collection,
-        progress_fn: impl 'static + FnMut(ImportProgress, bool) -> bool,
+        mut progress: ThrottlingProgressHandler<ImportProgress>,
     ) -> Result<Self> {
-        let mut progress = IncrementableProgress::new(progress_fn);
-        progress.call(ImportProgress::Extracting)?;
         let media_manager = target_col.media()?;
         let meta = Meta::from_archive(&mut archive)?;
         let data = ExchangeData::gather_from_archive(
@@ -102,7 +97,7 @@ impl ExchangeData {
         archive: &mut ZipArchive<File>,
         meta: &Meta,
         search: impl TryIntoSearch,
-        progress: &mut IncrementableProgress<ImportProgress>,
+        progress: &mut ThrottlingProgressHandler<ImportProgress>,
         with_scheduling: bool,
     ) -> Result<Self> {
         let tempfile = collection_to_tempfile(meta, archive)?;
@@ -110,7 +105,7 @@ impl ExchangeData {
         col.maybe_fix_invalid_ids()?;
         col.maybe_upgrade_scheduler()?;
 
-        progress.call(ImportProgress::Gathering)?;
+        progress.set(ImportProgress::Gathering)?;
         let mut data = ExchangeData::default();
         data.gather_data(&mut col, search, with_scheduling)?;
 

rslib/src/import_export/package/apkg/import/notes.rs

@@ -14,9 +14,9 @@ use super::media::MediaUseMap;
 use super::Context;
 use crate::import_export::package::media::safe_normalized_file_name;
 use crate::import_export::ImportProgress;
-use crate::import_export::IncrementableProgress;
 use crate::import_export::NoteLog;
 use crate::prelude::*;
+use crate::progress::ThrottlingProgressHandler;
 use crate::text::replace_media_refs;
 
 struct NoteContext<'a> {
@@ -164,7 +164,7 @@ impl<'n> NoteContext<'n> {
     fn import_notes(
         &mut self,
         notes: Vec<Note>,
-        progress: &mut IncrementableProgress<ImportProgress>,
+        progress: &mut ThrottlingProgressHandler<ImportProgress>,
     ) -> Result<()> {
         let mut incrementor = progress.incrementor(ImportProgress::Notes);
 
@@ -297,15 +297,15 @@ mod test {
     macro_rules! import_note {
         ($col:expr, $note:expr, $old_notetype:expr => $new_notetype:expr) => {{
             let mut media_map = MediaUseMap::default();
+            let mut progress = $col.new_progress_handler();
             let mut ctx = NoteContext::new(Usn(1), &mut $col, &mut media_map).unwrap();
             ctx.remapped_notetypes.insert($old_notetype, $new_notetype);
-            let mut progress = IncrementableProgress::new(|_, _| true);
             ctx.import_notes(vec![$note], &mut progress).unwrap();
             ctx.imports.log
         }};
         ($col:expr, $note:expr, $media_map:expr) => {{
+            let mut progress = $col.new_progress_handler();
             let mut ctx = NoteContext::new(Usn(1), &mut $col, &mut $media_map).unwrap();
-            let mut progress = IncrementableProgress::new(|_, _| true);
             ctx.import_notes(vec![$note], &mut progress).unwrap();
             ctx.imports.log
         }};

rslib/src/import_export/package/apkg/tests.rs

@@ -48,10 +48,9 @@ fn roundtrip_inner(legacy: bool) {
             true,
             legacy,
             None,
-            |_, _| true,
         )
         .unwrap();
-    target_col.import_apkg(&apkg_path, |_, _| true).unwrap();
+    target_col.import_apkg(&apkg_path).unwrap();
 
     target_col.assert_decks();
     target_col.assert_notetype(&notetype);

rslib/src/import_export/package/colpkg/export.rs

@@ -33,8 +33,8 @@ use crate::import_export::package::media::new_media_entry;
 use crate::import_export::package::media::MediaCopier;
 use crate::import_export::package::media::MediaIter;
 use crate::import_export::ExportProgress;
-use crate::import_export::IncrementableProgress;
 use crate::prelude::*;
+use crate::progress::ThrottlingProgressHandler;
 use crate::storage::SchemaVersion;
 
 /// Enable multithreaded compression if over this size. For smaller files,
@@ -48,10 +48,8 @@ impl Collection {
         out_path: impl AsRef<Path>,
         include_media: bool,
         legacy: bool,
-        progress_fn: impl 'static + FnMut(ExportProgress, bool) -> bool,
     ) -> Result<()> {
-        let mut progress = IncrementableProgress::new(progress_fn);
+        let mut progress = self.new_progress_handler();
-        progress.call(ExportProgress::File)?;
         let colpkg_name = out_path.as_ref();
         let temp_colpkg = new_tempfile_in_parent_of(colpkg_name)?;
         let src_path = self.col_path.clone();
@@ -87,7 +85,7 @@ fn export_collection_file(
     media_dir: Option<PathBuf>,
     legacy: bool,
     tr: &I18n,
-    progress: &mut IncrementableProgress<ExportProgress>,
+    progress: &mut ThrottlingProgressHandler<ExportProgress>,
 ) -> Result<()> {
     let meta = if legacy {
         Meta::new_legacy()
@@ -112,6 +110,7 @@ pub(crate) fn export_colpkg_from_data(
     tr: &I18n,
 ) -> Result<()> {
     let col_size = col_data.len();
+    let mut progress = ThrottlingProgressHandler::new(Default::default());
     export_collection(
         Meta::new(),
         out_path,
@@ -119,7 +118,7 @@ pub(crate) fn export_colpkg_from_data(
         col_size,
         MediaIter::empty(),
         tr,
-        &mut IncrementableProgress::new(|_, _| true),
+        &mut progress,
     )
 }
 
@@ -130,9 +129,8 @@ pub(crate) fn export_collection(
     col_size: usize,
     media: MediaIter,
     tr: &I18n,
-    progress: &mut IncrementableProgress<ExportProgress>,
+    progress: &mut ThrottlingProgressHandler<ExportProgress>,
 ) -> Result<()> {
-    progress.call(ExportProgress::File)?;
     let out_file = File::create(&out_path)?;
     let mut zip = ZipWriter::new(out_file);
 
@@ -217,7 +215,7 @@ fn write_media(
     meta: &Meta,
     zip: &mut ZipWriter<File>,
     media: MediaIter,
-    progress: &mut IncrementableProgress<ExportProgress>,
+    progress: &mut ThrottlingProgressHandler<ExportProgress>,
 ) -> Result<()> {
     let mut media_entries = vec![];
     write_media_files(meta, zip, media, &mut media_entries, progress)?;
@@ -261,7 +259,7 @@ fn write_media_files(
     zip: &mut ZipWriter<File>,
     media: MediaIter,
     media_entries: &mut Vec<MediaEntry>,
-    progress: &mut IncrementableProgress<ExportProgress>,
+    progress: &mut ThrottlingProgressHandler<ExportProgress>,
 ) -> Result<()> {
     let mut copier = MediaCopier::new(meta.zstd_compressed());
     let mut incrementor = progress.incrementor(ExportProgress::Media);

rslib/src/import_export/package/colpkg/import.rs

@@ -24,19 +24,17 @@ use crate::import_export::package::media::SafeMediaEntry;
 use crate::import_export::package::Meta;
 use crate::import_export::ImportError;
 use crate::import_export::ImportProgress;
-use crate::import_export::IncrementableProgress;
 use crate::media::MediaManager;
 use crate::prelude::*;
+use crate::progress::ThrottlingProgressHandler;
 
 pub fn import_colpkg(
     colpkg_path: &str,
     target_col_path: &str,
     target_media_folder: &Path,
     media_db: &Path,
-    progress_fn: impl 'static + FnMut(ImportProgress, bool) -> bool,
+    mut progress: ThrottlingProgressHandler<ImportProgress>,
 ) -> Result<()> {
-    let mut progress = IncrementableProgress::new(progress_fn);
-    progress.call(ImportProgress::File)?;
     let col_path = PathBuf::from(target_col_path);
     let mut tempfile = new_tempfile_in_parent_of(&col_path)?;
 
@@ -45,9 +43,9 @@ pub fn import_colpkg(
     let meta = Meta::from_archive(&mut archive)?;
 
     copy_collection(&mut archive, &mut tempfile, &meta)?;
-    progress.call(ImportProgress::File)?;
+    progress.set(ImportProgress::File)?;
     check_collection_and_mod_schema(tempfile.path())?;
-    progress.call(ImportProgress::File)?;
+    progress.set(ImportProgress::File)?;
 
     restore_media(
         &meta,
@@ -82,7 +80,7 @@ fn check_collection_and_mod_schema(col_path: &Path) -> Result<()> {
 
 fn restore_media(
     meta: &Meta,
-    progress: &mut IncrementableProgress<ImportProgress>,
+    progress: &mut ThrottlingProgressHandler<ImportProgress>,
     archive: &mut ZipArchive<File>,
     media_folder: &Path,
     media_db: &Path,
@@ -164,7 +162,7 @@ struct MediaComparer<'a>(Option<Box<GetChecksumFn<'a>>>);
 impl<'a> MediaComparer<'a> {
     fn new(
         meta: &Meta,
-        progress: &mut IncrementableProgress<ImportProgress>,
+        progress: &mut ThrottlingProgressHandler<ImportProgress>,
         media_manager: &'a MediaManager,
     ) -> Result<Self> {
         Ok(Self(if meta.media_list_is_hashmap() {

rslib/src/import_export/package/colpkg/tests.rs

@@ -40,7 +40,8 @@ fn roundtrip() -> Result<()> {
         // export to a file
         let col = collection_with_media(dir, name)?;
         let colpkg_name = dir.join(format!("{name}.colpkg"));
-        col.export_colpkg(&colpkg_name, true, legacy, |_, _| true)?;
+        let progress = col.new_progress_handler();
+        col.export_colpkg(&colpkg_name, true, legacy)?;
 
         // import into a new collection
         let anki2_name = dir
@@ -56,7 +57,7 @@ fn roundtrip() -> Result<()> {
             &anki2_name,
             &import_media_dir,
             &import_media_db,
-            |_, _| true,
+            progress,
         )?;
 
         // confirm collection imported
@@ -89,8 +90,7 @@ fn normalization_check_on_export() -> Result<()> {
     // manually write a file in the wrong encoding.
     write_file(col.media_folder.join("ぱぱ.jpg"), "nfd encoding")?;
     assert_eq!(
-        col.export_colpkg(&colpkg_name, true, false, |_, _| true,)
+        col.export_colpkg(&colpkg_name, true, false,).unwrap_err(),
-            .unwrap_err(),
         AnkiError::MediaCheckRequired
     );
     // file should have been cleaned up

rslib/src/import_export/text/csv/export.rs

@@ -15,7 +15,6 @@ use regex::Regex;
 use super::metadata::Delimiter;
 use crate::import_export::text::csv::metadata::DelimeterExt;
 use crate::import_export::ExportProgress;
-use crate::import_export::IncrementableProgress;
 use crate::notetype::RenderCardOutput;
 use crate::prelude::*;
 use crate::search::SearchNode;
@@ -32,10 +31,8 @@ impl Collection {
         path: &str,
         search: impl TryIntoSearch,
         with_html: bool,
-        progress_fn: impl 'static + FnMut(ExportProgress, bool) -> bool,
     ) -> Result<usize> {
-        let mut progress = IncrementableProgress::new(progress_fn);
+        let mut progress = self.new_progress_handler::<ExportProgress>();
-        progress.call(ExportProgress::File)?;
         let mut incrementor = progress.incrementor(ExportProgress::Cards);
 
         let mut writer = file_writer_with_header(path, with_html)?;
@@ -52,13 +49,8 @@ impl Collection {
         Ok(cards.len())
     }
 
-    pub fn export_note_csv(
+    pub fn export_note_csv(&mut self, mut request: ExportNoteCsvRequest) -> Result<usize> {
-        &mut self,
+        let mut progress = self.new_progress_handler::<ExportProgress>();
-        mut request: ExportNoteCsvRequest,
-        progress_fn: impl 'static + FnMut(ExportProgress, bool) -> bool,
-    ) -> Result<usize> {
-        let mut progress = IncrementableProgress::new(progress_fn);
-        progress.call(ExportProgress::File)?;
         let mut incrementor = progress.incrementor(ExportProgress::Notes);
 
         let guard = self.search_notes_into_table(Into::<SearchNode>::into(&mut request))?;

rslib/src/import_export/text/csv/import.rs

@@ -18,24 +18,19 @@ use crate::import_export::text::csv::metadata::Delimiter;
 use crate::import_export::text::ForeignData;
 use crate::import_export::text::ForeignNote;
 use crate::import_export::text::NameOrId;
-use crate::import_export::ImportProgress;
 use crate::import_export::NoteLog;
 use crate::prelude::*;
 use crate::text::strip_utf8_bom;
 
 impl Collection {
-    pub fn import_csv(
+    pub fn import_csv(&mut self, path: &str, metadata: CsvMetadata) -> Result<OpOutput<NoteLog>> {
-        &mut self,
+        let progress = self.new_progress_handler();
-        path: &str,
-        metadata: CsvMetadata,
-        progress_fn: impl 'static + FnMut(ImportProgress, bool) -> bool,
-    ) -> Result<OpOutput<NoteLog>> {
         let file = open_file(path)?;
         let mut ctx = ColumnContext::new(&metadata)?;
         let notes = ctx.deserialize_csv(file, metadata.delimiter())?;
         let mut data = ForeignData::from(metadata);
         data.notes = notes;
-        data.import(self, progress_fn)
+        data.import(self, progress)
     }
 }
 

rslib/src/import_export/text/import.rs

@@ -18,7 +18,6 @@ use crate::import_export::text::ForeignNotetype;
 use crate::import_export::text::ForeignTemplate;
 use crate::import_export::text::MatchScope;
 use crate::import_export::ImportProgress;
-use crate::import_export::IncrementableProgress;
 use crate::import_export::NoteLog;
 use crate::notes::field_checksum;
 use crate::notes::normalize_field;
@@ -26,16 +25,16 @@ use crate::notetype::CardGenContext;
 use crate::notetype::CardTemplate;
 use crate::notetype::NoteField;
 use crate::prelude::*;
+use crate::progress::ThrottlingProgressHandler;
 use crate::text::strip_html_preserving_media_filenames;
 
 impl ForeignData {
     pub fn import(
         self,
         col: &mut Collection,
-        progress_fn: impl 'static + FnMut(ImportProgress, bool) -> bool,
+        mut progress: ThrottlingProgressHandler<ImportProgress>,
     ) -> Result<OpOutput<NoteLog>> {
-        let mut progress = IncrementableProgress::new(progress_fn);
+        progress.set(ImportProgress::File)?;
-        progress.call(ImportProgress::File)?;
         col.transact(Op::Import, |col| {
             self.update_config(col)?;
             let mut ctx = Context::new(&self, col)?;
@@ -229,7 +228,7 @@ impl<'a> Context<'a> {
         notes: Vec<ForeignNote>,
         global_tags: &[String],
         updated_tags: &[String],
-        progress: &mut IncrementableProgress<ImportProgress>,
+        progress: &mut ThrottlingProgressHandler<ImportProgress>,
     ) -> Result<NoteLog> {
         let mut incrementor = progress.incrementor(ImportProgress::Notes);
         let mut log = new_note_log(self.dupe_resolution, notes.len() as u32);
@@ -654,8 +653,10 @@ mod test {
         data.add_note(&["same", "old"]);
         data.dupe_resolution = DupeResolution::Duplicate;
 
-        data.clone().import(&mut col, |_, _| true).unwrap();
+        let progress = col.new_progress_handler();
-        data.import(&mut col, |_, _| true).unwrap();
+        data.clone().import(&mut col, progress).unwrap();
+        let progress = col.new_progress_handler();
+        data.import(&mut col, progress).unwrap();
         assert_eq!(col.storage.notes_table_len(), 2);
     }
 
@@ -665,12 +666,13 @@ mod test {
         let mut data = ForeignData::with_defaults();
         data.add_note(&["same", "old"]);
         data.dupe_resolution = DupeResolution::Preserve;
-
+        let progress = col.new_progress_handler();
-        data.clone().import(&mut col, |_, _| true).unwrap();
+        data.clone().import(&mut col, progress).unwrap();
         assert_eq!(col.storage.notes_table_len(), 1);
 
         data.notes[0].fields[1].replace("new".to_string());
-        data.import(&mut col, |_, _| true).unwrap();
+        let progress = col.new_progress_handler();
+        data.import(&mut col, progress).unwrap();
         let notes = col.storage.get_all_notes();
         assert_eq!(notes.len(), 1);
         assert_eq!(notes[0].fields()[1], "old");
@@ -682,12 +684,13 @@ mod test {
         let mut data = ForeignData::with_defaults();
         data.add_note(&["same", "old"]);
         data.dupe_resolution = DupeResolution::Update;
-
+        let progress = col.new_progress_handler();
-        data.clone().import(&mut col, |_, _| true).unwrap();
+        data.clone().import(&mut col, progress).unwrap();
         assert_eq!(col.storage.notes_table_len(), 1);
 
         data.notes[0].fields[1].replace("new".to_string());
-        data.import(&mut col, |_, _| true).unwrap();
+        let progress = col.new_progress_handler();
+        data.import(&mut col, progress).unwrap();
         assert_eq!(col.storage.get_all_notes()[0].fields()[1], "new");
     }
 
@@ -698,13 +701,14 @@ mod test {
         data.add_note(&["same", "unchanged"]);
         data.add_note(&["same", "unchanged"]);
         data.dupe_resolution = DupeResolution::Update;
-
+        let progress = col.new_progress_handler();
-        data.clone().import(&mut col, |_, _| true).unwrap();
+        data.clone().import(&mut col, progress).unwrap();
         assert_eq!(col.storage.notes_table_len(), 2);
 
         data.notes[0].fields[1] = None;
         data.notes[1].fields.pop();
-        data.import(&mut col, |_, _| true).unwrap();
+        let progress = col.new_progress_handler();
+        data.import(&mut col, progress).unwrap();
         let notes = col.storage.get_all_notes();
         assert_eq!(notes[0].fields(), &["same", "unchanged"]);
         assert_eq!(notes[0].fields(), &["same", "unchanged"]);
@@ -719,13 +723,15 @@ mod test {
         let mut data = ForeignData::with_defaults();
         data.dupe_resolution = DupeResolution::Update;
         data.add_note(&["神", "new"]);
+        let progress = col.new_progress_handler();
 
-        data.clone().import(&mut col, |_, _| true).unwrap();
+        data.clone().import(&mut col, progress).unwrap();
         assert_eq!(col.storage.get_all_notes()[0].fields(), &["神", "new"]);
 
         col.set_config_bool(BoolKey::NormalizeNoteText, false, false)
             .unwrap();
-        data.import(&mut col, |_, _| true).unwrap();
+        let progress = col.new_progress_handler();
+        data.import(&mut col, progress).unwrap();
         let notes = col.storage.get_all_notes();
         assert_eq!(notes[0].fields(), &["神", "new"]);
         assert_eq!(notes[1].fields(), &["神", "new"]);
@@ -738,8 +744,8 @@ mod test {
         data.add_note(&["foo"]);
         data.notes[0].tags.replace(vec![String::from("bar")]);
         data.global_tags = vec![String::from("baz")];
-
+        let progress = col.new_progress_handler();
-        data.import(&mut col, |_, _| true).unwrap();
+        data.import(&mut col, progress).unwrap();
         assert_eq!(col.storage.get_all_notes()[0].tags, ["bar", "baz"]);
     }
 
@@ -750,8 +756,8 @@ mod test {
         data.add_note(&["foo"]);
         data.notes[0].tags.replace(vec![String::from("bar")]);
         data.global_tags = vec![String::from("baz")];
-
+        let progress = col.new_progress_handler();
-        data.import(&mut col, |_, _| true).unwrap();
+        data.import(&mut col, progress).unwrap();
         assert_eq!(col.storage.get_all_notes()[0].tags, ["bar", "baz"]);
     }
 
@@ -769,8 +775,8 @@ mod test {
         let mut data = ForeignData::with_defaults();
         data.match_scope = MatchScope::NotetypeAndDeck;
         data.add_note(&["foo", "new"]);
-
+        let progress = col.new_progress_handler();
-        data.import(&mut col, |_, _| true).unwrap();
+        data.import(&mut col, progress).unwrap();
         let notes = col.storage.get_all_notes();
         // same deck, should be updated
         assert_eq!(notes[0].fields()[1], "new");

rslib/src/import_export/text/json.rs

@@ -4,29 +4,20 @@
 use anki_io::read_file;
 
 use crate::import_export::text::ForeignData;
-use crate::import_export::ImportProgress;
 use crate::import_export::NoteLog;
 use crate::prelude::*;
 
 impl Collection {
-    pub fn import_json_file(
+    pub fn import_json_file(&mut self, path: &str) -> Result<OpOutput<NoteLog>> {
-        &mut self,
+        let progress = self.new_progress_handler();
-        path: &str,
-        mut progress_fn: impl 'static + FnMut(ImportProgress, bool) -> bool,
-    ) -> Result<OpOutput<NoteLog>> {
-        progress_fn(ImportProgress::Gathering, false);
         let slice = read_file(path)?;
         let data: ForeignData = serde_json::from_slice(&slice)?;
-        data.import(self, progress_fn)
+        data.import(self, progress)
     }
 
-    pub fn import_json_string(
+    pub fn import_json_string(&mut self, json: &str) -> Result<OpOutput<NoteLog>> {
-        &mut self,
+        let progress = self.new_progress_handler();
-        json: &str,
-        mut progress_fn: impl 'static + FnMut(ImportProgress, bool) -> bool,
-    ) -> Result<OpOutput<NoteLog>> {
-        progress_fn(ImportProgress::Gathering, false);
         let data: ForeignData = serde_json::from_str(json)?;
-        data.import(self, progress_fn)
+        data.import(self, progress)
     }
 }

rslib/src/lib.rs

@@ -28,6 +28,7 @@ pub mod notetype;
 pub mod ops;
 mod preferences;
 pub mod prelude;
+mod progress;
 pub mod revlog;
 pub mod scheduler;
 pub mod search;

rslib/src/media/check.rs

@@ -19,6 +19,8 @@ use crate::media::files::normalize_nfc_filename;
 use crate::media::files::trash_folder;
 use crate::media::MediaManager;
 use crate::prelude::*;
+use crate::progress::ThrottlingProgressHandler;
+use crate::sync::media::progress::MediaCheckProgress;
 use crate::sync::media::MAX_INDIVIDUAL_MEDIA_FILE_SIZE;
 use crate::text::extract_media_refs;
 use crate::text::normalize_to_nfc;
@@ -45,31 +47,25 @@ struct MediaFolderCheck {
     oversize: Vec<String>,
 }
 
-pub struct MediaChecker<'a, 'b, P>
+impl Collection {
-where
+    pub fn media_checker(&mut self) -> Result<MediaChecker<'_>> {
-    P: FnMut(usize) -> bool,
+        MediaChecker::new(self)
-{
+    }
-    ctx: &'a mut Collection,
-    mgr: &'b MediaManager,
-    progress_cb: P,
-    checked: usize,
 }
 
-impl<P> MediaChecker<'_, '_, P>
+pub struct MediaChecker<'a> {
-where
+    col: &'a mut Collection,
-    P: FnMut(usize) -> bool,
+    media: MediaManager,
-{
+    progress: ThrottlingProgressHandler<MediaCheckProgress>,
-    pub(crate) fn new<'a, 'b>(
-        ctx: &'a mut Collection,
-        mgr: &'b MediaManager,
-        progress_cb: P,
-    ) -> MediaChecker<'a, 'b, P> {
-        MediaChecker {
-            ctx,
-            mgr,
-            progress_cb,
-            checked: 0,
 }
+
+impl MediaChecker<'_> {
+    pub(crate) fn new(col: &mut Collection) -> Result<MediaChecker<'_>> {
+        Ok(MediaChecker {
+            media: col.media()?,
+            progress: col.new_progress_handler(),
+            col,
+        })
     }
 
     pub fn check(&mut self) -> Result<MediaCheckOutput> {
@@ -91,7 +87,7 @@ where
 
     pub fn summarize_output(&self, output: &mut MediaCheckOutput) -> String {
         let mut buf = String::new();
-        let tr = &self.ctx.tr;
+        let tr = &self.col.tr;
 
         // top summary area
         if output.trash_count > 0 {
@@ -179,6 +175,10 @@ where
         buf
     }
 
+    fn increment_progress(&mut self) -> Result<()> {
+        self.progress.increment(|p| &mut p.checked)
+    }
+
     /// Check all the files in the media folder.
     ///
     /// - Renames files with invalid names
@@ -186,13 +186,11 @@ where
     /// - Gathers a list of all files
     fn check_media_folder(&mut self) -> Result<MediaFolderCheck> {
         let mut out = MediaFolderCheck::default();
-        for dentry in self.mgr.media_folder.read_dir()? {
+
+        for dentry in self.media.media_folder.read_dir()? {
             let dentry = dentry?;
 
-            self.checked += 1;
+            self.increment_progress()?;
-            if self.checked % 10 == 0 {
-                self.fire_progress_cb()?;
-            }
 
             // if the filename is not valid unicode, skip it
             let fname_os = dentry.file_name();
@@ -220,7 +218,7 @@ where
             if let Some(norm_name) = filename_if_normalized(disk_fname) {
                 out.files.push(norm_name.into_owned());
             } else {
-                match data_for_file(&self.mgr.media_folder, disk_fname)? {
+                match data_for_file(&self.media.media_folder, disk_fname)? {
                     Some(data) => {
                         let norm_name = self.normalize_file(disk_fname, data)?;
                         out.renamed
@@ -242,38 +240,27 @@ where
     /// Write file data to normalized location, moving old file to trash.
     fn normalize_file<'a>(&mut self, disk_fname: &'a str, data: Vec<u8>) -> Result<Cow<'a, str>> {
         // add a copy of the file using the correct name
-        let fname = self.mgr.add_file(disk_fname, &data)?;
+        let fname = self.media.add_file(disk_fname, &data)?;
         debug!(from = disk_fname, to = &fname.as_ref(), "renamed");
         assert_ne!(fname.as_ref(), disk_fname);
 
         // remove the original file
-        let path = &self.mgr.media_folder.join(disk_fname);
+        let path = &self.media.media_folder.join(disk_fname);
         fs::remove_file(path)?;
 
         Ok(fname)
     }
 
-    fn fire_progress_cb(&mut self) -> Result<()> {
-        if (self.progress_cb)(self.checked) {
-            Ok(())
-        } else {
-            Err(AnkiError::Interrupted)
-        }
-    }
-
     /// Returns the count and total size of the files in the trash folder
     fn files_in_trash(&mut self) -> Result<(u64, u64)> {
-        let trash = trash_folder(&self.mgr.media_folder)?;
+        let trash = trash_folder(&self.media.media_folder)?;
         let mut total_files = 0;
         let mut total_bytes = 0;
 
         for dentry in trash.read_dir()? {
             let dentry = dentry?;
 
-            self.checked += 1;
+            self.increment_progress()?;
-            if self.checked % 10 == 0 {
-                self.fire_progress_cb()?;
-            }
 
             if dentry.file_name() == ".DS_Store" {
                 continue;
@@ -289,15 +276,12 @@ where
     }
 
     pub fn empty_trash(&mut self) -> Result<()> {
-        let trash = trash_folder(&self.mgr.media_folder)?;
+        let trash = trash_folder(&self.media.media_folder)?;
 
         for dentry in trash.read_dir()? {
             let dentry = dentry?;
 
-            self.checked += 1;
+            self.increment_progress()?;
-            if self.checked % 10 == 0 {
-                self.fire_progress_cb()?;
-            }
 
             fs::remove_file(dentry.path())?;
         }
@@ -306,17 +290,14 @@ where
     }
 
     pub fn restore_trash(&mut self) -> Result<()> {
-        let trash = trash_folder(&self.mgr.media_folder)?;
+        let trash = trash_folder(&self.media.media_folder)?;
 
         for dentry in trash.read_dir()? {
             let dentry = dentry?;
 
-            self.checked += 1;
+            self.increment_progress()?;
-            if self.checked % 10 == 0 {
-                self.fire_progress_cb()?;
-            }
 
-            let orig_path = self.mgr.media_folder.join(dentry.file_name());
+            let orig_path = self.media.media_folder.join(dentry.file_name());
             // if the original filename doesn't exist, we can just rename
             if let Err(e) = fs::metadata(&orig_path) {
                 if e.kind() == io::ErrorKind::NotFound {
@@ -329,7 +310,7 @@ where
                 let fname_os = dentry.file_name();
                 let fname = fname_os.to_string_lossy();
                 if let Some(data) = data_for_file(&trash, fname.as_ref())? {
-                    let _new_fname = self.mgr.add_file(fname.as_ref(), &data)?;
+                    let _new_fname = self.media.add_file(fname.as_ref(), &data)?;
                 } else {
                     debug!(?fname, "file disappeared while restoring trash");
                 }
@@ -346,17 +327,14 @@ where
         renamed: &HashMap<String, String>,
     ) -> Result<HashMap<String, Vec<NoteId>>> {
         let mut referenced_files = HashMap::new();
-        let notetypes = self.ctx.get_all_notetypes()?;
+        let notetypes = self.col.get_all_notetypes()?;
         let mut collection_modified = false;
 
-        let nids = self.ctx.search_notes_unordered("")?;
+        let nids = self.col.search_notes_unordered("")?;
-        let usn = self.ctx.usn()?;
+        let usn = self.col.usn()?;
         for nid in nids {
-            self.checked += 1;
+            self.increment_progress()?;
-            if self.checked % 10 == 0 {
+            let mut note = self.col.storage.get_note(nid)?.unwrap();
-                self.fire_progress_cb()?;
-            }
-            let mut note = self.ctx.storage.get_note(nid)?.unwrap();
             let nt = notetypes.get(&note.notetype_id).ok_or_else(|| {
                 AnkiError::db_error("missing note type", DbErrorKind::MissingEntity)
             })?;
@@ -366,12 +344,16 @@ where
                     .or_insert_with(Vec::new)
                     .push(nid)
             };
-            if fix_and_extract_media_refs(&mut note, &mut tracker, renamed, &self.mgr.media_folder)?
+            if fix_and_extract_media_refs(
-            {
+                &mut note,
+                &mut tracker,
+                renamed,
+                &self.media.media_folder,
+            )? {
                 // note was modified, needs saving
                 note.prepare_for_update(nt, false)?;
                 note.set_modified(usn);
-                self.ctx.storage.update_note(&note)?;
+                self.col.storage.update_note(&note)?;
                 collection_modified = true;
             }
 
@@ -557,10 +539,8 @@ pub(crate) mod test {
         write_file(mgr.media_folder.join("_under.jpg"), "foo")?;
         write_file(mgr.media_folder.join("unused.jpg"), "foo")?;
 
-        let progress = |_n| true;
-
         let (output, report) = {
-            let mut checker = MediaChecker::new(&mut col, &mgr, progress);
+            let mut checker = col.media_checker()?;
             let output = checker.check()?;
             let summary = checker.summarize_output(&mut output.clone());
             (output, summary)
@@ -628,9 +608,7 @@ Unused: unused.jpg
         let trash_folder = trash_folder(&mgr.media_folder)?;
         write_file(trash_folder.join("test.jpg"), "test")?;
 
-        let progress = |_n| true;
+        let mut checker = col.media_checker()?;
-
-        let mut checker = MediaChecker::new(&mut col, &mgr, progress);
         checker.restore_trash()?;
 
         // file should have been moved to media folder
@@ -644,7 +622,7 @@ Unused: unused.jpg
         // are equal
         write_file(trash_folder.join("test.jpg"), "test")?;
 
-        let mut checker = MediaChecker::new(&mut col, &mgr, progress);
+        let mut checker = col.media_checker()?;
         checker.restore_trash()?;
 
         assert_eq!(files_in_dir(&trash_folder), Vec::<String>::new());
@@ -656,7 +634,7 @@ Unused: unused.jpg
         // but rename if required
         write_file(trash_folder.join("test.jpg"), "test2")?;
 
-        let mut checker = MediaChecker::new(&mut col, &mgr, progress);
+        let mut checker = col.media_checker()?;
         checker.restore_trash()?;
 
         assert_eq!(files_in_dir(&trash_folder), Vec::<String>::new());
@@ -677,10 +655,8 @@ Unused: unused.jpg
 
         write_file(mgr.media_folder.join("ぱぱ.jpg"), "nfd encoding")?;
 
-        let progress = |_n| true;
-
         let mut output = {
-            let mut checker = MediaChecker::new(&mut col, &mgr, progress);
+            let mut checker = col.media_checker()?;
             checker.check()
         }?;
 

rslib/src/media/mod.rs

@@ -16,6 +16,7 @@ use crate::media::files::mtime_as_i64;
 use crate::media::files::remove_files;
 use crate::media::files::sha1_of_data;
 use crate::prelude::*;
+use crate::progress::ThrottlingProgressHandler;
 use crate::sync::http_client::HttpSyncClient;
 use crate::sync::login::SyncAuth;
 use crate::sync::media::database::client::changetracker::ChangeTracker;
@@ -139,10 +140,11 @@ impl MediaManager {
     }
 
     /// Sync media.
-    pub async fn sync_media<F>(self, progress: F, auth: SyncAuth) -> Result<()>
+    pub async fn sync_media(
-    where
+        self,
-        F: FnMut(MediaSyncProgress) -> bool,
+        progress: ThrottlingProgressHandler<MediaSyncProgress>,
-    {
+        auth: SyncAuth,
+    ) -> Result<()> {
         let client = HttpSyncClient::new(auth);
         let mut syncer = MediaSyncer::new(self, progress, client)?;
         syncer.sync().await

rslib/src/progress.rs

@@ -1,54 +1,131 @@
 // Copyright: Ankitects Pty Ltd and contributors
 // License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 
+use std::marker::PhantomData;
 use std::sync::Arc;
 use std::sync::Mutex;
 
 use anki_i18n::I18n;
 use futures::future::AbortHandle;
 
-use super::Backend;
 use crate::dbcheck::DatabaseCheckProgress;
+use crate::error::AnkiError;
+use crate::error::Result;
 use crate::import_export::ExportProgress;
 use crate::import_export::ImportProgress;
+use crate::prelude::Collection;
 use crate::sync::collection::normal::NormalSyncProgress;
 use crate::sync::collection::progress::FullSyncProgress;
 use crate::sync::collection::progress::SyncStage;
+use crate::sync::media::progress::MediaCheckProgress;
 use crate::sync::media::progress::MediaSyncProgress;
 
-pub(super) struct ThrottlingProgressHandler {
+/// Stores progress state that can be updated cheaply, and will update a
-    pub state: Arc<Mutex<ProgressState>>,
+/// Mutex-protected copy that other threads can check, if more than 0.1
-    pub last_update: coarsetime::Instant,
+/// secs has elapsed since the previous update.
+/// If another thread has set the `want_abort` flag on the shared state,
+/// then the next non-throttled update will fail with [AnkiError::Interrupted].
+/// Automatically updates the shared state on creation, with the default
+/// value for the type.
+#[derive(Debug, Default)]
+pub struct ThrottlingProgressHandler<P: Into<Progress> + Default> {
+    pub(crate) state: P,
+    shared_state: Arc<Mutex<ProgressState>>,
+    last_shared_update: coarsetime::Instant,
 }
 
-impl ThrottlingProgressHandler {
+impl<P: Into<Progress> + Default + Clone> ThrottlingProgressHandler<P> {
-    /// Returns true if should continue.
+    pub(crate) fn new(shared_state: Arc<Mutex<ProgressState>>) -> Self {
-    pub(super) fn update(&mut self, progress: impl Into<Progress>, throttle: bool) -> bool {
+        let initial = P::default();
-        let now = coarsetime::Instant::now();
+        {
-        if throttle && now.duration_since(self.last_update).as_f64() < 0.1 {
+            let mut guard = shared_state.lock().unwrap();
-            return true;
+            guard.last_progress = Some(initial.clone().into());
-        }
-        self.last_update = now;
-        let mut guard = self.state.lock().unwrap();
-        guard.last_progress.replace(progress.into());
-        let want_abort = guard.want_abort;
             guard.want_abort = false;
-        !want_abort
+        }
+        Self {
+            shared_state,
+            state: initial,
+            ..Default::default()
         }
     }
 
-pub(super) struct ProgressState {
+    /// Overwrite the currently-stored state. This does not throttle, and should
+    /// be used when you want to ensure the UI state gets updated, and
+    /// ensure that the abort flag is checked between expensive steps.
+    pub(crate) fn set(&mut self, progress: P) -> Result<()> {
+        self.update(false, |state| *state = progress)
+    }
+
+    /// Mutate the currently-stored state, and maybe update shared state.
+    pub(crate) fn update(&mut self, throttle: bool, mutator: impl FnOnce(&mut P)) -> Result<()> {
+        mutator(&mut self.state);
+
+        let now = coarsetime::Instant::now();
+        if throttle && now.duration_since(self.last_shared_update).as_f64() < 0.1 {
+            return Ok(());
+        }
+        self.last_shared_update = now;
+
+        let mut guard = self.shared_state.lock().unwrap();
+        guard.last_progress.replace(self.state.clone().into());
+
+        if std::mem::take(&mut guard.want_abort) {
+            Err(AnkiError::Interrupted)
+        } else {
+            Ok(())
+        }
+    }
+
+    /// Check the abort flag, and trigger a UI update if it was throttled.
+    pub(crate) fn check_cancelled(&mut self) -> Result<()> {
+        self.set(self.state.clone())
+    }
+
+    /// An alternative to incrementor() below, that can be used across function
+    /// calls easily, as it continues from the previous state.
+    pub(crate) fn increment(&mut self, accessor: impl Fn(&mut P) -> &mut usize) -> Result<()> {
+        let field = accessor(&mut self.state);
+        *field += 1;
+        if *field % 17 == 0 {
+            self.update(true, |_| ())?;
+        }
+        Ok(())
+    }
+
+    /// Returns an [Incrementor] with an `increment()` function for use in
+    /// loops.
+    pub(crate) fn incrementor<'inc, 'progress: 'inc, 'map: 'inc>(
+        &'progress mut self,
+        mut count_map: impl 'map + FnMut(usize) -> P,
+    ) -> Incrementor<'inc, impl FnMut(usize) -> Result<()> + 'inc> {
+        Incrementor::new(move |u| self.update(true, |p| *p = count_map(u)))
+    }
+
+    /// Stopgap for returning a progress fn compliant with the media code.
+    pub(crate) fn media_db_fn(
+        &mut self,
+        count_map: impl 'static + Fn(usize) -> P,
+    ) -> Result<impl FnMut(usize) -> bool + '_>
+    where
+        P: Into<Progress>,
+    {
+        Ok(move |count| self.update(true, |p| *p = count_map(count)).is_ok())
+    }
+}
+
+#[derive(Default, Debug)]
+pub struct ProgressState {
     pub want_abort: bool,
     pub last_progress: Option<Progress>,
 }
 
 // fixme: this should support multiple abort handles.
-pub(super) type AbortHandleSlot = Arc<Mutex<Option<AbortHandle>>>;
+pub(crate) type AbortHandleSlot = Arc<Mutex<Option<AbortHandle>>>;
 
-#[derive(Clone, Copy)]
+#[derive(Clone, Copy, Debug)]
-pub(super) enum Progress {
+pub enum Progress {
     MediaSync(MediaSyncProgress),
-    MediaCheck(u32),
+    MediaCheck(MediaCheckProgress),
     FullSync(FullSyncProgress),
     NormalSync(NormalSyncProgress),
     DatabaseCheck(DatabaseCheckProgress),
@@ -56,7 +133,7 @@ pub(super) enum Progress {
     Export(ExportProgress),
 }
 
-pub(super) fn progress_to_proto(
+pub(crate) fn progress_to_proto(
     progress: Option<Progress>,
     tr: &I18n,
 ) -> anki_proto::collection::Progress {
@@ -66,7 +143,7 @@ pub(super) fn progress_to_proto(
                 anki_proto::collection::progress::Value::MediaSync(media_sync_progress(p, tr))
             }
             Progress::MediaCheck(n) => anki_proto::collection::progress::Value::MediaCheck(
-                tr.media_check_checked(n).into(),
+                tr.media_check_checked(n.checked).into(),
             ),
             Progress::FullSync(p) => anki_proto::collection::progress::Value::FullSync(
                 anki_proto::collection::progress::FullSync {
@@ -113,8 +190,8 @@ pub(super) fn progress_to_proto(
                 anki_proto::collection::progress::Value::DatabaseCheck(
                     anki_proto::collection::progress::DatabaseCheck {
                         stage,
-                        stage_total,
+                        stage_total: stage_total as u32,
-                        stage_current,
+                        stage_current: stage_current as u32,
                     },
                 )
             }
@@ -175,22 +252,72 @@ impl From<MediaSyncProgress> for Progress {
     }
 }
 
+impl From<MediaCheckProgress> for Progress {
+    fn from(p: MediaCheckProgress) -> Self {
+        Progress::MediaCheck(p)
+    }
+}
+
 impl From<NormalSyncProgress> for Progress {
     fn from(p: NormalSyncProgress) -> Self {
         Progress::NormalSync(p)
     }
 }
 
-impl Backend {
+impl From<DatabaseCheckProgress> for Progress {
-    pub(super) fn new_progress_handler(&self) -> ThrottlingProgressHandler {
+    fn from(p: DatabaseCheckProgress) -> Self {
-        {
+        Progress::DatabaseCheck(p)
-            let mut guard = self.progress_state.lock().unwrap();
-            guard.want_abort = false;
-            guard.last_progress = None;
-        }
-        ThrottlingProgressHandler {
-            state: Arc::clone(&self.progress_state),
-            last_update: coarsetime::Instant::now(),
     }
 }
+
+impl From<ImportProgress> for Progress {
+    fn from(p: ImportProgress) -> Self {
+        Progress::Import(p)
+    }
+}
+
+impl From<ExportProgress> for Progress {
+    fn from(p: ExportProgress) -> Self {
+        Progress::Export(p)
+    }
+}
+
+impl Collection {
+    pub fn new_progress_handler<P: Into<Progress> + Default + Clone>(
+        &self,
+    ) -> ThrottlingProgressHandler<P> {
+        ThrottlingProgressHandler::new(self.state.progress.clone())
+    }
+}
+
+pub(crate) struct Incrementor<'f, F: 'f + FnMut(usize) -> Result<()>> {
+    update_fn: F,
+    count: usize,
+    update_interval: usize,
+    _phantom: PhantomData<&'f ()>,
+}
+
+impl<'f, F: 'f + FnMut(usize) -> Result<()>> Incrementor<'f, F> {
+    fn new(update_fn: F) -> Self {
+        Self {
+            update_fn,
+            count: 0,
+            update_interval: 17,
+            _phantom: PhantomData,
+        }
+    }
+
+    /// Increments the progress counter, periodically triggering an update.
+    /// Returns [AnkiError::Interrupted] if the operation should be cancelled.
+    pub(crate) fn increment(&mut self) -> Result<()> {
+        self.count += 1;
+        if self.count % self.update_interval != 0 {
+            return Ok(());
+        }
+        (self.update_fn)(self.count)
+    }
+
+    pub(crate) fn count(&self) -> usize {
+        self.count
+    }
 }

rslib/src/sync/collection/changes.rs

@@ -19,7 +19,6 @@ use crate::error::SyncErrorKind;
 use crate::notetype::NotetypeSchema11;
 use crate::prelude::*;
 use crate::sync::collection::normal::ClientSyncState;
-use crate::sync::collection::normal::NormalSyncProgress;
 use crate::sync::collection::normal::NormalSyncer;
 use crate::sync::collection::protocol::SyncProtocol;
 use crate::sync::collection::start::ServerSyncState;
@@ -52,10 +51,7 @@ pub struct DecksAndConfig {
     config: Vec<DeckConfSchema11>,
 }
 
-impl<F> NormalSyncer<'_, F>
+impl NormalSyncer<'_> {
-where
-    F: FnMut(NormalSyncProgress, bool),
-{
     // This was assumed to a cheap operation when originally written - it didn't
     // anticipate the large deck trees and note types some users would create.
     // They should be chunked in the future, like other objects. Syncing tags
@@ -79,16 +75,18 @@ where
             "sending"
         );
 
-        self.progress.local_update += local.notetypes.len()
+        self.progress.update(false, |p| {
+            p.local_update += local.notetypes.len()
                 + local.decks_and_config.decks.len()
                 + local.decks_and_config.config.len()
                 + local.tags.len();
+        })?;
         let remote = self
             .server
             .apply_changes(ApplyChangesRequest { changes: local }.try_into_sync_request()?)
             .await?
             .json()?;
-        self.fire_progress_cb(true);
+        self.progress.check_cancelled()?;
 
         debug!(
             notetypes = remote.notetypes.len(),
@@ -98,13 +96,15 @@ where
             "received"
         );
 
-        self.progress.remote_update += remote.notetypes.len()
+        self.progress.update(false, |p| {
+            p.remote_update += remote.notetypes.len()
                 + remote.decks_and_config.decks.len()
                 + remote.decks_and_config.config.len()
                 + remote.tags.len();
+        })?;
 
         self.col.apply_changes(remote, state.server_usn)?;
-        self.fire_progress_cb(true);
+        self.progress.check_cancelled()?;
         Ok(())
     }
 }

rslib/src/sync/collection/chunks.rs

@@ -17,7 +17,6 @@ use crate::serde::deserialize_int_from_number;
 use crate::storage::card::data::card_data_string;
 use crate::storage::card::data::CardData;
 use crate::sync::collection::normal::ClientSyncState;
-use crate::sync::collection::normal::NormalSyncProgress;
 use crate::sync::collection::normal::NormalSyncer;
 use crate::sync::collection::protocol::EmptyInput;
 use crate::sync::collection::protocol::SyncProtocol;
@@ -87,10 +86,7 @@ pub struct CardEntry {
     pub data: String,
 }
 
-impl<F> NormalSyncer<'_, F>
+impl NormalSyncer<'_> {
-where
-    F: FnMut(NormalSyncProgress, bool),
-{
     pub(in crate::sync) async fn process_chunks_from_server(
         &mut self,
         state: &ClientSyncState,
@@ -106,13 +102,14 @@ where
                 "received"
             );
 
-            self.progress.remote_update +=
+            self.progress.update(false, |p| {
-                chunk.cards.len() + chunk.notes.len() + chunk.revlog.len();
+                p.remote_update += chunk.cards.len() + chunk.notes.len() + chunk.revlog.len()
+            })?;
 
             let done = chunk.done;
             self.col.apply_chunk(chunk, state.pending_usn)?;
 
-            self.fire_progress_cb(true);
+            self.progress.check_cancelled()?;
 
             if done {
                 return Ok(());
@@ -138,14 +135,15 @@ where
                 "sending"
             );
 
-            self.progress.local_update +=
+            self.progress.update(false, |p| {
-                chunk.cards.len() + chunk.notes.len() + chunk.revlog.len();
+                p.local_update += chunk.cards.len() + chunk.notes.len() + chunk.revlog.len()
+            })?;
 
             self.server
                 .apply_chunk(ApplyChunkRequest { chunk }.try_into_sync_request()?)
                 .await?;
 
-            self.fire_progress_cb(true);
+            self.progress.check_cancelled()?;
 
             if done {
                 return Ok(());

rslib/src/sync/collection/download.rs

@@ -9,9 +9,7 @@ use anki_io::write_file;
 use crate::collection::CollectionBuilder;
 use crate::prelude::*;
 use crate::storage::SchemaVersion;
-use crate::sync::collection::progress::FullSyncProgressFn;
 use crate::sync::collection::protocol::EmptyInput;
-use crate::sync::collection::protocol::SyncProtocol;
 use crate::sync::error::HttpResult;
 use crate::sync::error::OrHttpErr;
 use crate::sync::http_client::HttpSyncClient;
@@ -19,21 +17,21 @@ use crate::sync::login::SyncAuth;
 
 impl Collection {
     /// Download collection from AnkiWeb. Caller must re-open afterwards.
-    pub async fn full_download(
+    pub async fn full_download(self, auth: SyncAuth) -> Result<()> {
-        self,
+        self.full_download_with_server(HttpSyncClient::new(auth))
-        auth: SyncAuth,
+            .await
-        progress_fn: FullSyncProgressFn,
-    ) -> Result<()> {
-        let mut server = HttpSyncClient::new(auth);
-        server.set_full_sync_progress_fn(Some(progress_fn));
-        self.full_download_with_server(server).await
     }
 
-    pub(crate) async fn full_download_with_server(self, server: HttpSyncClient) -> Result<()> {
+    // pub for tests
+    pub(super) async fn full_download_with_server(self, server: HttpSyncClient) -> Result<()> {
         let col_path = self.col_path.clone();
         let _col_folder = col_path.parent().or_invalid("couldn't get col_folder")?;
+        let progress = self.new_progress_handler();
         self.close(None)?;
-        let out_data = server.download(EmptyInput::request()).await?.data;
+        let out_data = server
+            .download_with_progress(EmptyInput::request(), progress)
+            .await?
+            .data;
         // check file ok
         let temp_file = new_tempfile_in_parent_of(&col_path)?;
         write_file(temp_file.path(), out_data)?;

rslib/src/sync/collection/finish.rs

@@ -3,15 +3,11 @@
 
 use crate::prelude::*;
 use crate::sync::collection::normal::ClientSyncState;
-use crate::sync::collection::normal::NormalSyncProgress;
 use crate::sync::collection::normal::NormalSyncer;
 use crate::sync::collection::protocol::EmptyInput;
 use crate::sync::collection::protocol::SyncProtocol;
 
-impl<F> NormalSyncer<'_, F>
+impl NormalSyncer<'_> {
-where
-    F: FnMut(NormalSyncProgress, bool),
-{
     pub(in crate::sync) async fn finalize(&mut self, state: &ClientSyncState) -> Result<()> {
         let new_server_mtime = self.server.finish(EmptyInput::request()).await?.json()?;
         self.col.finalize_sync(state, new_server_mtime)

rslib/src/sync/collection/normal.rs

@@ -9,6 +9,7 @@ use crate::error::AnkiError;
 use crate::error::SyncError;
 use crate::error::SyncErrorKind;
 use crate::prelude::Usn;
+use crate::progress::ThrottlingProgressHandler;
 use crate::sync::collection::progress::SyncStage;
 use crate::sync::collection::protocol::EmptyInput;
 use crate::sync::collection::protocol::SyncProtocol;
@@ -16,11 +17,10 @@ use crate::sync::collection::status::online_sync_status_check;
 use crate::sync::http_client::HttpSyncClient;
 use crate::sync::login::SyncAuth;
 
-pub struct NormalSyncer<'a, F> {
+pub struct NormalSyncer<'a> {
     pub(in crate::sync) col: &'a mut Collection,
     pub(in crate::sync) server: HttpSyncClient,
-    pub(in crate::sync) progress: NormalSyncProgress,
+    pub(in crate::sync) progress: ThrottlingProgressHandler<NormalSyncProgress>,
-    pub(in crate::sync) progress_fn: F,
 }
 
 #[derive(Default, Debug, Clone, Copy)]
@@ -54,29 +54,17 @@ pub struct ClientSyncState {
     pub(in crate::sync) pending_usn: Usn,
 }
 
-impl<F> NormalSyncer<'_, F>
+impl NormalSyncer<'_> {
-where
+    pub fn new(col: &mut Collection, server: HttpSyncClient) -> NormalSyncer<'_> {
-    F: FnMut(NormalSyncProgress, bool),
-{
-    pub fn new(col: &mut Collection, server: HttpSyncClient, progress_fn: F) -> NormalSyncer<'_, F>
-    where
-        F: FnMut(NormalSyncProgress, bool),
-    {
         NormalSyncer {
+            progress: col.new_progress_handler(),
             col,
             server,
-            progress: NormalSyncProgress::default(),
-            progress_fn,
         }
     }
 
-    pub(in crate::sync) fn fire_progress_cb(&mut self, throttle: bool) {
-        (self.progress_fn)(self.progress, throttle)
-    }
-
     pub async fn sync(&mut self) -> error::Result<SyncOutput> {
         debug!("fetching meta...");
-        self.fire_progress_cb(false);
         let local = self.col.sync_meta()?;
         let state = online_sync_status_check(local, &mut self.server).await?;
         debug!(?state, "fetched");
@@ -120,8 +108,8 @@ where
     /// Sync. Caller must have created a transaction, and should call
     /// abort on failure.
     async fn normal_sync_inner(&mut self, mut state: ClientSyncState) -> error::Result<SyncOutput> {
-        self.progress.stage = SyncStage::Syncing;
+        self.progress
-        self.fire_progress_cb(false);
+            .update(false, |p| p.stage = SyncStage::Syncing)?;
 
         debug!("start");
         self.start_and_process_deletions(&state).await?;
@@ -132,8 +120,8 @@ where
         debug!("begin stream to server");
         self.send_chunks_to_server(&state).await?;
 
-        self.progress.stage = SyncStage::Finalizing;
+        self.progress
-        self.fire_progress_cb(false);
+            .update(false, |p| p.stage = SyncStage::Finalizing)?;
 
         debug!("sanity check");
         self.sanity_check().await?;
@@ -164,15 +152,8 @@ impl From<ClientSyncState> for SyncOutput {
 }
 
 impl Collection {
-    pub async fn normal_sync<F>(
+    pub async fn normal_sync(&mut self, auth: SyncAuth) -> error::Result<SyncOutput> {
-        &mut self,
+        NormalSyncer::new(self, HttpSyncClient::new(auth))
-        auth: SyncAuth,
-        progress_fn: F,
-    ) -> error::Result<SyncOutput>
-    where
-        F: FnMut(NormalSyncProgress, bool),
-    {
-        NormalSyncer::new(self, HttpSyncClient::new(auth), progress_fn)
             .sync()
             .await
     }

rslib/src/sync/collection/progress.rs

@@ -27,5 +27,3 @@ pub async fn sync_abort(auth: SyncAuth) -> error::Result<()> {
         .await?
         .json()
 }
-
-pub type FullSyncProgressFn = Box<dyn FnMut(FullSyncProgress, bool) + Send + Sync + 'static>;

rslib/src/sync/collection/sanity.rs

@@ -10,7 +10,6 @@ use tracing::info;
 use crate::error::SyncErrorKind;
 use crate::prelude::*;
 use crate::serde::default_on_invalid;
-use crate::sync::collection::normal::NormalSyncProgress;
 use crate::sync::collection::normal::NormalSyncer;
 use crate::sync::collection::protocol::SyncProtocol;
 use crate::sync::request::IntoSyncRequest;
@@ -51,10 +50,7 @@ pub struct SanityCheckDueCounts {
     pub review: u32,
 }
 
-impl<F> NormalSyncer<'_, F>
+impl NormalSyncer<'_> {
-where
-    F: FnMut(NormalSyncProgress, bool),
-{
     /// Caller should force full sync after rolling back.
     pub(in crate::sync) async fn sanity_check(&mut self) -> Result<()> {
         let local_counts = self.col.storage.sanity_check_info()?;

rslib/src/sync/collection/start.rs

@@ -11,15 +11,11 @@ use crate::sync::collection::chunks::ChunkableIds;
 use crate::sync::collection::graves::ApplyGravesRequest;
 use crate::sync::collection::graves::Graves;
 use crate::sync::collection::normal::ClientSyncState;
-use crate::sync::collection::normal::NormalSyncProgress;
 use crate::sync::collection::normal::NormalSyncer;
 use crate::sync::collection::protocol::SyncProtocol;
 use crate::sync::request::IntoSyncRequest;
 
-impl<F> NormalSyncer<'_, F>
+impl NormalSyncer<'_> {
-where
-    F: FnMut(NormalSyncProgress, bool),
-{
     pub(in crate::sync) async fn start_and_process_deletions(
         &mut self,
         state: &ClientSyncState,
@@ -58,16 +54,20 @@ where
 
         while let Some(chunk) = local.take_chunk() {
             debug!("sending graves chunk");
-            self.progress.local_remove += chunk.cards.len() + chunk.notes.len() + chunk.decks.len();
+            self.progress.update(false, |p| {
+                p.local_remove += chunk.cards.len() + chunk.notes.len() + chunk.decks.len()
+            })?;
             self.server
                 .apply_graves(ApplyGravesRequest { chunk }.try_into_sync_request()?)
                 .await?;
-            self.fire_progress_cb(true);
+            self.progress.check_cancelled()?;
         }
 
-        self.progress.remote_remove = remote.cards.len() + remote.notes.len() + remote.decks.len();
+        self.progress.update(false, |p| {
+            p.remote_remove = remote.cards.len() + remote.notes.len() + remote.decks.len()
+        })?;
         self.col.apply_graves(remote, state.server_usn)?;
-        self.fire_progress_cb(true);
+        self.progress.check_cancelled()?;
         debug!("applied server graves");
 
         Ok(())

rslib/src/sync/collection/tests.rs

@@ -34,11 +34,9 @@ use crate::revlog::RevlogEntry;
 use crate::search::SortMode;
 use crate::sync::collection::graves::ApplyGravesRequest;
 use crate::sync::collection::meta::MetaRequest;
-use crate::sync::collection::normal::NormalSyncProgress;
 use crate::sync::collection::normal::NormalSyncer;
 use crate::sync::collection::normal::SyncActionRequired;
 use crate::sync::collection::normal::SyncOutput;
-use crate::sync::collection::progress::FullSyncProgress;
 use crate::sync::collection::protocol::EmptyInput;
 use crate::sync::collection::protocol::SyncProtocol;
 use crate::sync::collection::start::StartRequest;
@@ -111,10 +109,6 @@ fn unwrap_sync_err_kind(err: AnkiError) -> SyncErrorKind {
     kind
 }
 
-fn norm_progress(_: NormalSyncProgress, _: bool) {}
-
-fn full_progress(_: FullSyncProgress, _: bool) {}
-
 #[tokio::test]
 async fn host_key() -> Result<()> {
     with_active_server(|mut client| async move {
@@ -209,7 +203,7 @@ async fn aborting_is_idempotent() -> Result<()> {
 #[tokio::test]
 async fn new_syncs_cancel_old_ones() -> Result<()> {
     with_active_server(|mut client| async move {
-        let ctx = SyncTestContext::new(client.partial_clone());
+        let ctx = SyncTestContext::new(client.clone());
 
         // start a sync
         let req = StartRequest {
@@ -296,7 +290,7 @@ async fn sanity_check_should_roll_back_and_force_full_sync() -> Result<()> {
             .execute("update decks set usn=0 where id=?", [deck.id])?;
 
         // the sync should fail
-        let err = NormalSyncer::new(&mut col1, ctx.cloned_client(), norm_progress)
+        let err = NormalSyncer::new(&mut col1, ctx.cloned_client())
             .sync()
             .await
             .unwrap_err();
@@ -349,7 +343,7 @@ async fn sync_errors_should_prompt_db_check() -> Result<()> {
         col1.storage.db.execute("update notetypes set usn=0", [])?;
 
         // the sync should fail
-        let err = NormalSyncer::new(&mut col1, ctx.cloned_client(), norm_progress)
+        let err = NormalSyncer::new(&mut col1, ctx.cloned_client())
             .sync()
             .await
             .unwrap_err();
@@ -362,7 +356,7 @@ async fn sync_errors_should_prompt_db_check() -> Result<()> {
         assert_eq!(out.required, SyncActionRequired::NoChanges);
 
         // and the client should be able to sync again without a forced one-way sync
-        let err = NormalSyncer::new(&mut col1, ctx.cloned_client(), norm_progress)
+        let err = NormalSyncer::new(&mut col1, ctx.cloned_client())
             .sync()
             .await
             .unwrap_err();
@@ -417,9 +411,7 @@ async fn string_grave_ids_are_handled() -> Result<()> {
 #[tokio::test]
 async fn invalid_uploads_should_be_handled() -> Result<()> {
     with_active_server(|client| async move {
-        let mut ctx = SyncTestContext::new(client);
+        let ctx = SyncTestContext::new(client);
-        ctx.client
-            .set_full_sync_progress_fn(Some(Box::new(full_progress)));
         let res = ctx
             .client
             .upload(b"fake data".to_vec().try_into_sync_request()?)
@@ -494,7 +486,7 @@ impl SyncTestContext {
     }
 
     async fn normal_sync(&self, col: &mut Collection) -> SyncOutput {
-        NormalSyncer::new(col, self.cloned_client(), norm_progress)
+        NormalSyncer::new(col, self.cloned_client())
             .sync()
             .await
             .unwrap()
@@ -513,9 +505,7 @@ impl SyncTestContext {
     }
 
     fn cloned_client(&self) -> HttpSyncClient {
-        let mut client = self.client.partial_clone();
+        self.client.clone()
-        client.set_full_sync_progress_fn(Some(Box::new(full_progress)));
-        client
     }
 }
 

rslib/src/sync/collection/upload.rs

@@ -18,8 +18,6 @@ use crate::collection::CollectionBuilder;
 use crate::error::SyncErrorKind;
 use crate::prelude::*;
 use crate::storage::SchemaVersion;
-use crate::sync::collection::progress::FullSyncProgressFn;
-use crate::sync::collection::protocol::SyncProtocol;
 use crate::sync::error::HttpResult;
 use crate::sync::error::OrHttpErr;
 use crate::sync::http_client::HttpSyncClient;
@@ -34,15 +32,16 @@ pub const CORRUPT_MESSAGE: &str =
 
 impl Collection {
     /// Upload collection to AnkiWeb. Caller must re-open afterwards.
-    pub async fn full_upload(self, auth: SyncAuth, progress_fn: FullSyncProgressFn) -> Result<()> {
+    pub async fn full_upload(self, auth: SyncAuth) -> Result<()> {
-        let mut server = HttpSyncClient::new(auth);
+        self.full_upload_with_server(HttpSyncClient::new(auth))
-        server.set_full_sync_progress_fn(Some(progress_fn));
+            .await
-        self.full_upload_with_server(server).await
     }
 
-    pub(crate) async fn full_upload_with_server(mut self, server: HttpSyncClient) -> Result<()> {
+    // pub for tests
+    pub(super) async fn full_upload_with_server(mut self, server: HttpSyncClient) -> Result<()> {
         self.before_upload()?;
         let col_path = self.col_path.clone();
+        let progress = self.new_progress_handler();
         self.close(Some(SchemaVersion::V18))?;
         let col_data = fs::read(&col_path)?;
 
@@ -55,7 +54,7 @@ impl Collection {
         }
 
         match server
-            .upload(col_data.try_into_sync_request()?)
+            .upload_with_progress(col_data.try_into_sync_request()?, progress)
             .await?
             .upload_response()
         {

rslib/src/sync/http_client/full_sync.rs

@@ -7,8 +7,8 @@ use std::time::Duration;
 use tokio::select;
 use tokio::time::interval;
 
+use crate::progress::ThrottlingProgressHandler;
 use crate::sync::collection::progress::FullSyncProgress;
-use crate::sync::collection::progress::FullSyncProgressFn;
 use crate::sync::collection::protocol::EmptyInput;
 use crate::sync::collection::protocol::SyncMethod;
 use crate::sync::collection::upload::UploadResponse;
@@ -19,49 +19,47 @@ use crate::sync::request::SyncRequest;
 use crate::sync::response::SyncResponse;
 
 impl HttpSyncClient {
-    pub fn set_full_sync_progress_fn(&mut self, func: Option<FullSyncProgressFn>) {
+    fn full_sync_progress_monitor(
-        *self.full_sync_progress_fn.lock().unwrap() = func;
+        &self,
-    }
+        sending: bool,
-
+        mut progress: ThrottlingProgressHandler<FullSyncProgress>,
-    fn full_sync_progress_monitor(&self, sending: bool) -> (IoMonitor, impl Future<Output = ()>) {
+    ) -> (IoMonitor, impl Future<Output = ()>) {
-        let mut progress = FullSyncProgress {
-            transferred_bytes: 0,
-            total_bytes: 0,
-        };
-        let mut progress_fn = self
-            .full_sync_progress_fn
-            .lock()
-            .unwrap()
-            .take()
-            .expect("progress func was not set");
         let io_monitor = IoMonitor::new();
         let io_monitor2 = io_monitor.clone();
         let update_progress = async move {
             let mut interval = interval(Duration::from_millis(100));
             loop {
                 interval.tick().await;
+                let (total_bytes, transferred_bytes) = {
                     let guard = io_monitor2.0.lock().unwrap();
-                progress.total_bytes = if sending {
+                    (
+                        if sending {
                             guard.total_bytes_to_send
                         } else {
                             guard.total_bytes_to_receive
-                } as usize;
+                        },
-                progress.transferred_bytes = if sending {
+                        if sending {
                             guard.bytes_sent
                         } else {
                             guard.bytes_received
-                } as usize;
+                        },
-                progress_fn(progress, true)
+                    )
+                };
+                _ = progress.update(false, |p| {
+                    p.total_bytes = total_bytes as usize;
+                    p.transferred_bytes = transferred_bytes as usize;
+                })
             }
         };
         (io_monitor, update_progress)
     }
 
-    pub(super) async fn download_inner(
+    pub(in super::super) async fn download_with_progress(
         &self,
         req: SyncRequest<EmptyInput>,
+        progress: ThrottlingProgressHandler<FullSyncProgress>,
     ) -> HttpResult<SyncResponse<Vec<u8>>> {
-        let (io_monitor, progress_fut) = self.full_sync_progress_monitor(false);
+        let (io_monitor, progress_fut) = self.full_sync_progress_monitor(false, progress);
         let output = self.request_ext(SyncMethod::Download, req, io_monitor);
         select! {
             _ = progress_fut => unreachable!(),
@@ -69,11 +67,12 @@ impl HttpSyncClient {
         }
     }
 
-    pub(super) async fn upload_inner(
+    pub(in super::super) async fn upload_with_progress(
         &self,
         req: SyncRequest<Vec<u8>>,
+        progress: ThrottlingProgressHandler<FullSyncProgress>,
     ) -> HttpResult<SyncResponse<UploadResponse>> {
-        let (io_monitor, progress_fut) = self.full_sync_progress_monitor(true);
+        let (io_monitor, progress_fut) = self.full_sync_progress_monitor(true, progress);
         let output = self.request_ext(SyncMethod::Upload, req, io_monitor);
         select! {
             _ = progress_fut => unreachable!(),

rslib/src/sync/http_client/mod.rs

@@ -5,7 +5,6 @@ pub(crate) mod full_sync;
 pub(crate) mod io_monitor;
 mod protocol;
 
-use std::sync::Mutex;
 use std::time::Duration;
 
 use reqwest::Client;
@@ -14,7 +13,6 @@ use reqwest::StatusCode;
 use reqwest::Url;
 
 use crate::notes;
-use crate::sync::collection::progress::FullSyncProgressFn;
 use crate::sync::collection::protocol::AsSyncEndpoint;
 use crate::sync::error::HttpError;
 use crate::sync::error::HttpResult;
@@ -25,6 +23,7 @@ use crate::sync::request::header_and_stream::SYNC_HEADER_NAME;
 use crate::sync::request::SyncRequest;
 use crate::sync::response::SyncResponse;
 
+#[derive(Clone)]
 pub struct HttpSyncClient {
     /// Set to the empty string for initial login
     pub sync_key: String,
@@ -32,7 +31,6 @@ pub struct HttpSyncClient {
     client: Client,
     pub endpoint: Url,
     pub io_timeout: Duration,
-    full_sync_progress_fn: Mutex<Option<FullSyncProgressFn>>,
 }
 
 impl HttpSyncClient {
@@ -46,19 +44,6 @@ impl HttpSyncClient {
                 .endpoint
                 .unwrap_or_else(|| Url::try_from("https://sync.ankiweb.net/").unwrap()),
             io_timeout,
-            full_sync_progress_fn: Mutex::new(None),
-        }
-    }
-
-    #[cfg(test)]
-    pub fn partial_clone(&self) -> Self {
-        Self {
-            sync_key: self.sync_key.clone(),
-            session_key: self.session_key.clone(),
-            client: self.client.clone(),
-            endpoint: self.endpoint.clone(),
-            full_sync_progress_fn: Mutex::new(None),
-            io_timeout: self.io_timeout,
         }
     }
 

rslib/src/sync/http_client/protocol.rs

@@ -4,6 +4,7 @@
 use async_trait::async_trait;
 
 use crate::prelude::TimestampMillis;
+use crate::progress::ThrottlingProgressHandler;
 use crate::sync::collection::changes::ApplyChangesRequest;
 use crate::sync::collection::changes::UnchunkedChanges;
 use crate::sync::collection::chunks::ApplyChunkRequest;
@@ -97,11 +98,13 @@ impl SyncProtocol for HttpSyncClient {
     }
 
     async fn upload(&self, req: SyncRequest<Vec<u8>>) -> HttpResult<SyncResponse<UploadResponse>> {
-        self.upload_inner(req).await
+        self.upload_with_progress(req, ThrottlingProgressHandler::default())
+            .await
     }
 
     async fn download(&self, req: SyncRequest<EmptyInput>) -> HttpResult<SyncResponse<Vec<u8>>> {
-        self.download_inner(req).await
+        self.download_with_progress(req, ThrottlingProgressHandler::default())
+            .await
     }
 }
 

rslib/src/sync/media/progress.rs

@@ -9,3 +9,9 @@ pub struct MediaSyncProgress {
     pub uploaded_files: usize,
     pub uploaded_deletions: usize,
 }
+
+#[derive(Debug, Default, Clone, Copy)]
+#[repr(transparent)]
+pub struct MediaCheckProgress {
+    pub checked: usize,
+}

rslib/src/sync/media/syncer.rs

@@ -10,6 +10,7 @@ use crate::error::SyncErrorKind;
 use crate::media::files::mtime_as_i64;
 use crate::media::MediaManager;
 use crate::prelude::*;
+use crate::progress::ThrottlingProgressHandler;
 use crate::sync::http_client::HttpSyncClient;
 use crate::sync::media::begin::SyncBeginRequest;
 use crate::sync::media::begin::SyncBeginResponse;
@@ -30,41 +31,25 @@ use crate::sync::media::MAX_MEDIA_FILES_IN_ZIP;
 use crate::sync::request::IntoSyncRequest;
 use crate::version;
 
-pub struct MediaSyncer<P>
+pub struct MediaSyncer {
-where
-    P: FnMut(MediaSyncProgress) -> bool,
-{
     mgr: MediaManager,
     client: HttpSyncClient,
-    progress_cb: P,
+    progress: ThrottlingProgressHandler<MediaSyncProgress>,
-    progress: MediaSyncProgress,
 }
 
-impl<P> MediaSyncer<P>
+impl MediaSyncer {
-where
-    P: FnMut(MediaSyncProgress) -> bool,
-{
     pub fn new(
         mgr: MediaManager,
-        progress_cb: P,
+        progress: ThrottlingProgressHandler<MediaSyncProgress>,
         client: HttpSyncClient,
-    ) -> Result<MediaSyncer<P>> {
+    ) -> Result<MediaSyncer> {
         Ok(MediaSyncer {
             mgr,
             client,
-            progress_cb,
+            progress,
-            progress: Default::default(),
         })
     }
 
-    fn fire_progress_cb(&mut self) -> Result<()> {
-        if (self.progress_cb)(self.progress) {
-            Ok(())
-        } else {
-            Err(AnkiError::Interrupted)
-        }
-    }
-
     pub async fn sync(&mut self) -> Result<()> {
         self.sync_inner().await.map_err(|e| {
             debug!("sync error: {:?}", e);
@@ -100,8 +85,6 @@ where
             self.finalize_sync().await?;
         }
 
-        self.fire_progress_cb()?;
-
         debug!("media sync complete");
 
         Ok(())
@@ -129,16 +112,9 @@ where
 
     /// Make sure media DB is up to date.
     fn register_changes(&mut self) -> Result<()> {
-        // make borrow checker happy
+        let progress_cb = |checked| self.progress.update(true, |p| p.checked = checked).is_ok();
-        let progress = &mut self.progress;
+        ChangeTracker::new(self.mgr.media_folder.as_path(), progress_cb)
-        let progress_cb = &mut self.progress_cb;
+            .register_changes(&self.mgr.db)
-
-        let progress = |checked| {
-            progress.checked = checked;
-            (progress_cb)(*progress)
-        };
-
-        ChangeTracker::new(self.mgr.media_folder.as_path(), progress).register_changes(&self.mgr.db)
     }
 
     async fn fetch_changes(&mut self, mut meta: MediaDatabaseMetadata) -> Result<()> {
@@ -157,16 +133,15 @@ where
             }
             last_usn = batch.last().unwrap().usn;
 
-            self.progress.checked += batch.len();
+            self.progress.update(false, |p| p.checked += batch.len())?;
-            self.fire_progress_cb()?;
 
             let (to_download, to_delete, to_remove_pending) =
                 changes::determine_required_changes(&self.mgr.db, batch)?;
 
             // file removal
             self.mgr.remove_files(to_delete.as_slice())?;
-            self.progress.downloaded_deletions += to_delete.len();
+            self.progress
-            self.fire_progress_cb()?;
+                .update(false, |p| p.downloaded_deletions += to_delete.len())?;
 
             // file download
             let mut downloaded = vec![];
@@ -189,8 +164,7 @@ where
                 dl_fnames = &dl_fnames[len..];
                 downloaded.extend(download_batch);
 
-                self.progress.downloaded_files += len;
+                self.progress.update(false, |p| p.downloaded_files += len)?;
-                self.fire_progress_cb()?;
             }
 
             // then update the DB
@@ -227,8 +201,8 @@ where
                 None => {
                     // discard zip info and retry batch - not particularly efficient,
                     // but this is a corner case
-                    self.progress.checked += pending.len();
+                    self.progress
-                    self.fire_progress_cb()?;
+                        .update(false, |p| p.checked += pending.len())?;
                     continue;
                 }
                 Some(data) => zip_files_for_upload(data)?,
@@ -245,9 +219,10 @@ where
                 .take(reply.processed)
                 .partition(|e| e.sha1.is_some());
 
-            self.progress.uploaded_files += processed_files.len();
+            self.progress.update(false, |p| {
-            self.progress.uploaded_deletions += processed_deletions.len();
+                p.uploaded_files += processed_files.len();
-            self.fire_progress_cb()?;
+                p.uploaded_deletions += processed_deletions.len();
+            })?;
 
             let fnames: Vec<_> = processed_files
                 .into_iter()

rslib/src/sync/media/tests.rs

@@ -15,6 +15,7 @@ use reqwest::Client;
 use crate::error::Result;
 use crate::media::MediaManager;
 use crate::prelude::AnkiError;
+use crate::progress::ThrottlingProgressHandler;
 use crate::sync::collection::protocol::AsSyncEndpoint;
 use crate::sync::collection::tests::with_active_server;
 use crate::sync::collection::tests::SyncTestContext;
@@ -104,7 +105,7 @@ async fn legacy_session_key_works() -> Result<()> {
 #[tokio::test]
 async fn sanity_check() -> Result<()> {
     with_active_server(|client| async move {
-        let ctx = SyncTestContext::new(client.partial_clone());
+        let ctx = SyncTestContext::new(client.clone());
         let media1 = ctx.media1();
         ctx.sync_media1().await?;
         // may be non-zero when testing on external endpoint
@@ -134,8 +135,8 @@ async fn sanity_check() -> Result<()> {
     .await
 }
 
-fn ignore_progress(_progress: MediaSyncProgress) -> bool {
+fn ignore_progress() -> ThrottlingProgressHandler<MediaSyncProgress> {
-    true
+    ThrottlingProgressHandler::new(Default::default())
 }
 
 impl SyncTestContext {
@@ -149,13 +150,13 @@ impl SyncTestContext {
 
     async fn sync_media1(&self) -> Result<()> {
         let mut syncer =
-            MediaSyncer::new(self.media1(), ignore_progress, self.client.partial_clone()).unwrap();
+            MediaSyncer::new(self.media1(), ignore_progress(), self.client.clone()).unwrap();
         syncer.sync().await
     }
 
     async fn sync_media2(&self) -> Result<()> {
         let mut syncer =
-            MediaSyncer::new(self.media2(), ignore_progress, self.client.partial_clone()).unwrap();
+            MediaSyncer::new(self.media2(), ignore_progress(), self.client.clone()).unwrap();
         syncer.sync().await
     }
 
@@ -171,7 +172,7 @@ impl SyncTestContext {
 #[tokio::test]
 async fn media_roundtrip() -> Result<()> {
     with_active_server(|client| async move {
-        let ctx = SyncTestContext::new(client.partial_clone());
+        let ctx = SyncTestContext::new(client.clone());
         let media1 = ctx.media1();
         let media2 = ctx.media2();
         ctx.sync_media1().await?;
@@ -219,7 +220,7 @@ async fn media_roundtrip() -> Result<()> {
 #[tokio::test]
 async fn parallel_requests() -> Result<()> {
     with_active_server(|client| async move {
-        let ctx = SyncTestContext::new(client.partial_clone());
+        let ctx = SyncTestContext::new(client.clone());
         let media1 = ctx.media1();
         let media2 = ctx.media2();
         ctx.sleep();