This PR replaces the existing Python-driven sync server with a new one in Rust.
The new server supports both collection and media syncing, and is compatible
with both the new protocol mentioned below, and older clients. A setting has
been added to the preferences screen to point Anki to a local server, and a
similar setting is likely to come to AnkiMobile soon.
Documentation is available here: <https://docs.ankiweb.net/sync-server.html>
In addition to the new server and refactoring, this PR also makes changes to the
sync protocol. The existing sync protocol places payloads and metadata inside a
multipart POST body, which causes a few headaches:
- Legacy clients build the request in a non-deterministic order, meaning the
entire request needs to be scanned to extract the metadata.
- Reqwest's multipart API directly writes the multipart body, without exposing
the resulting stream to us, making it harder to track the progress of the
transfer. We've been relying on a patched version of reqwest for timeouts,
which is a pain to keep up to date.
To address these issues, the metadata is now sent in a HTTP header, with the
data payload sent directly in the body. Instead of the slower gzip, we now
use zstd. The old timeout handling code has been replaced with a new implementation
that wraps the request and response body streams to track progress, allowing us
to drop the git dependencies for reqwest, hyper-timeout and tokio-io-timeout.
The main other change to the protocol is that one-way syncs no longer need to
downgrade the collection to schema 11 prior to sending.
1. Add outer brackets.
2. Coalesce aggregate, because `null and true` is `null` in SQL land,
so cards that were not introduced, but manually rescheduled in the
period of interest, would not show up in a negated search.
* Relax chrono specification for AnkiDroid
https://github.com/ankidroid/Anki-Android-Backend/pull/251
* Add AnkiDroid service and AnkiDroid customizations
Most of the work here was done by David in the Backend repo; integrating
it into this repo for ease of future maintenance.
Based on 5d9f262f4c
with some tweaks:
- Protobuf imports have been fixed to match the recent refactor
- FatalError has been renamed to AnkidroidPanicError
- Tweaks to the desktop code to deal with the extra arg to open_collection,
and exclude AnkiDroid service methods from our Python code.
* Refactor AnkiDroid's DB code to avoid uses of unsafe
The Rust community appear to have converged on tracing - it's used by
the Rust compiler, and receives close to 10x the number of downloads
that slog does. Its API is more ergonomic, and it does a much nicer
job with async rust.
To make this change, we no longer pass around explicit loggers, and rely
on a globally-registered one. The log file location has been changed
from one in each profile folder to a single one in the base folder. This
will remain empty for most users, since only errors are logged by default,
but may be useful for debugging future changes.
The existing architecture serializes all cards and revlog entries in
the search range into a protobuf message, which the web frontend needs
to decode and then process. The thinking at the time was that this would
make it easier for add-ons to add extra graphs, but in the ~2.5 years
since the new graphs were introduced, no add-ons appear to have taken
advantage of it.
The cards and revlog entries can grow quite large on large collections -
on a collection I tested with approximately 2.5M reviews, the serialized
data is about 110MB, which is a lot to have to deserialize in JavaScript.
This commit shifts the preliminary processing of the data to the Rust end,
which means the data is able to be processed faster, and less needs to
be sent to the frontend. On the test collection above, this reduces the
serialized data from about 110MB to about 160KB, resulting in a more
than 2x performance improvement, and reducing frontend memory usage from
about 400MB to about 40MB.
This also makes #2043 more feasible - while it is still about 50-100%
slower than protobufjs, with the much smaller message size, the difference
is only about 10ms.
* Run cargo +nightly fmt
* Latest prost-build includes clippy workaround
* Tweak Rust protobuf imports
- Avoid use of stringify!(), as JetBrains editors get confused by it
- Stop merging all protobuf symbols into a single namespace
* Remove some unnecessary qualifications
Found via IntelliJ lint
* Migrate some asserts to assert_eq/ne
* Remove mention of node_modules exclusion
This no longer seems to be necessary after migrating away from Bazel,
and excluding it means TS/Svelte files can't be edited properly.
This reverts commit 09cb8b3cf6.
Overhead on larger folders/slower devices is more than I originally
anticipated, and can run into multiple seconds. This seems to be
particularly egregious on mobile, which I presume is due to sandboxing
overhead.
* Remove deprecated `and_hms()`
* Update chrono
* Update licenses and fix script
* Remove deprecated Date struct
* Remove chrono pin
* Skip format check on .vscode
Was failing for no reason.
* Replace deprecated chrono functions
* Add cargo-deny to update-licenses & pin versions (dae)
* Remove time 0.1 dependency (dae)
We don't need to wait for chrono 0.5; it was provided behind a legacy
feature flag.
(for upgrading users, please see the notes at the bottom)
Bazel brought a lot of nice things to the table, such as rebuilds based on
content changes instead of modification times, caching of build products,
detection of incorrect build rules via a sandbox, and so on. Rewriting the build
in Bazel was also an opportunity to improve on the Makefile-based build we had
prior, which was pretty poor: most dependencies were external or not pinned, and
the build graph was poorly defined and mostly serialized. It was not uncommon
for fresh checkouts to fail due to floating dependencies, or for things to break
when trying to switch to an older commit.
For day-to-day development, I think Bazel served us reasonably well - we could
generally switch between branches while being confident that builds would be
correct and reasonably fast, and not require full rebuilds (except on Windows,
where the lack of a sandbox and the TS rules would cause build breakages when TS
files were renamed/removed).
Bazel achieves that reliability by defining rules for each programming language
that define how source files should be turned into outputs. For the rules to
work with Bazel's sandboxing approach, they often have to reimplement or
partially bypass the standard tools that each programming language provides. The
Rust rules call Rust's compiler directly for example, instead of using Cargo,
and the Python rules extract each PyPi package into a separate folder that gets
added to sys.path.
These separate language rules allow proper declaration of inputs and outputs,
and offer some advantages such as caching of build products and fine-grained
dependency installation. But they also bring some downsides:
- The rules don't always support use-cases/platforms that the standard language
tools do, meaning they need to be patched to be used. I've had to contribute a
number of patches to the Rust, Python and JS rules to unblock various issues.
- The dependencies we use with each language sometimes make assumptions that do
not hold in Bazel, meaning they either need to be pinned or patched, or the
language rules need to be adjusted to accommodate them.
I was hopeful that after the initial setup work, things would be relatively
smooth-sailing. Unfortunately, that has not proved to be the case. Things
frequently broke when dependencies or the language rules were updated, and I
began to get frustrated at the amount of Anki development time I was instead
spending on build system upkeep. It's now about 2 years since switching to
Bazel, and I think it's time to cut losses, and switch to something else that's
a better fit.
The new build system is based on a small build tool called Ninja, and some
custom Rust code in build/. This means that to build Anki, Bazel is no longer
required, but Ninja and Rust need to be installed on your system. Python and
Node toolchains are automatically downloaded like in Bazel.
This new build system should result in faster builds in some cases:
- Because we're using cargo to build now, Rust builds are able to take advantage
of pipelining and incremental debug builds, which we didn't have with Bazel.
It's also easier to override the default linker on Linux/macOS, which can
further improve speeds.
- External Rust crates are now built with opt=1, which improves performance
of debug builds.
- Esbuild is now used to transpile TypeScript, instead of invoking the TypeScript
compiler. This results in faster builds, by deferring typechecking to test/check
time, and by allowing more work to happen in parallel.
As an example of the differences, when testing with the mold linker on Linux,
adding a new message to tags.proto (which triggers a recompile of the bulk of
the Rust and TypeScript code) results in a compile that goes from about 22s on
Bazel to about 7s in the new system. With the standard linker, it's about 9s.
Some other changes of note:
- Our Rust workspace now uses cargo-hakari to ensure all packages agree on
available features, preventing unnecessary rebuilds.
- pylib/anki is now a PEP420 implicit namespace, avoiding the need to merge
source files and generated files into a single folder for running. By telling
VSCode about the extra search path, code completion now works with generated
files without needing to symlink them into the source folder.
- qt/aqt can't use PEP420 as it's difficult to get rid of aqt/__init__.py.
Instead, the generated files are now placed in a separate _aqt package that's
added to the path.
- ts/lib is now exposed as @tslib, so the source code and generated code can be
provided under the same namespace without a merging step.
- MyPy and PyLint are now invoked once for the entire codebase.
- dprint will be used to format TypeScript/json files in the future instead of
the slower prettier (currently turned off to avoid causing conflicts). It can
automatically defer to prettier when formatting Svelte files.
- svelte-check is now used for typechecking our Svelte code, which revealed a
few typing issues that went undetected with the old system.
- The Jest unit tests now work on Windows as well.
If you're upgrading from Bazel, updated usage instructions are in docs/development.md and docs/build.md. A summary of the changes:
- please remove node_modules and .bazel
- install rustup (https://rustup.rs/)
- install rsync if not already installed (on windows, use pacman - see docs/windows.md)
- install Ninja (unzip from https://github.com/ninja-build/ninja/releases/tag/v1.11.1 and
place on your path, or from your distro/homebrew if it's 1.10+)
- update .vscode/settings.json from .vscode.dist
* Fix reparented_name not correctly handling tags that are prefixes of the
new parent
To reproduce the issue:
1. Add two tags: `a` and `ab`.
2. From the browser's sidebar, drag & drop `a` into `ab`.
Result: panic
* Fix reparent_tags panicking if new parent is a child of source tag
This is the "foo, foo::bar" case that should be a no-op.
* Add more tests for tag reparenting
* Add crate snafu
* Replace all inline structs in AnkiError
* Derive Snafu on AnkiError
* Use snafu for card type errors
* Use snafu whatever error for InvalidInput
* Use snafu for NotFoundError and improve message
* Use snafu for FileIoError to attach context
Remove IoError.
Add some context-attaching helpers to replace code returning bare
io::Errors.
* Add more context-attaching io helpers
* Add message, context and backtrace to new snafus
* Utilize error context and backtrace on frontend
* Rename LocalizedError -> BackendError.
* Remove DocumentedError.
* Have all backend exceptions inherit BackendError.
* Rename localized(_description) -> message
* Remove accidentally committed experimental trait
* invalid_input_context -> ok_or_invalid
* ensure_valid_input! -> require!
* Always return `Err` from `invalid_input!`
Instead of a Result to unwrap, the macro accepts a source error now.
* new_tempfile_in_parent -> new_tempfile_in_parent_of
* ok_or_not_found -> or_not_found
* ok_or_invalid -> or_invalid
* Add crate convert_case
* Use unqualified lowercase type name
* Remove uses of snafu::ensure
* Allow public construction of InvalidInputErrors (dae)
Needed to port the AnkiDroid changes.
* Make into_protobuf() public (dae)
Also required for AnkiDroid. Not sure why it worked previously - possible
bug in older Rust version?
