e767d84bea
We do not make all transactions [IMMEDIATE](https://www.sqlite.org/lang_transaction.html#deferred_immediate_and_exclusive_transactions) for more parallelism -- at least read transactions can be made DEFERRED to run in parallel w/o any drawbacks. But if we make write transactions DEFERRED also w/o any external locking, then they are upgraded from read to write ones on the first write statement. This has some drawbacks: - If there are other write transactions, we block the thread and the db connection until upgraded. Also if some reader comes then, it has to get next, less used connection with a worse per-connection page cache. - If a transaction is blocked for more than busy_timeout, it fails with SQLITE_BUSY. - Configuring busy_timeout is not the best way to manage transaction timeouts, we would prefer it to be integrated with Rust/tokio asyncs. Moreover, SQLite implements waiting using sleeps. - If upon a successful upgrade to a write transaction the db has been modified by another one, the transaction has to be rolled back and retried. It is an extra work in terms of CPU/battery. - Maybe minor, but we lose some fairness in servicing write transactions, i.e. we service them in the order of the first write statement, not in the order they come. The only pro of making write transactions DEFERRED w/o the external locking is some parallelism between them. Also we have an option to make write transactions IMMEDIATE, also w/o the external locking. But then the most of cons above are still valid. Instead, if we perform all write transactions under an async mutex, the only cons is losing some parallelism for write transactions.
Delta Chat Rust
Deltachat-core written in Rust
Installing Rust and Cargo
To download and install the official compiler for the Rust programming language, and the Cargo package manager, run the command in your user environment:
$ curl https://sh.rustup.rs -sSf | sh
On Windows, you may need to also install Perl to be able to compile deltachat-core.
Using the CLI client
Compile and run Delta Chat Core command line utility, using cargo:
$ RUST_LOG=repl=info cargo run -p deltachat-repl -- ~/deltachat-db
where ~/deltachat-db is the database file. Delta Chat will create it if it does not exist.
Optionally, install deltachat-repl binary with
$ cargo install --path deltachat-repl/
and run as
$ deltachat-repl ~/deltachat-db
Configure your account (if not already configured):
Delta Chat Core is awaiting your commands.
> set addr your@email.org
> set mail_pw yourpassword
> configure
Connect to your mail server (if already configured):
> connect
Create a contact:
> addcontact yourfriends@email.org
Command executed successfully.
List contacts:
> listcontacts
Contact#10: <name unset> <yourfriends@email.org>
Contact#1: Me √√ <your@email.org>
Create a chat with your friend and send a message:
> createchat 10
Single#10 created successfully.
> chat 10
Single#10: yourfriends@email.org [yourfriends@email.org]
> send hi
Message sent.
If yourfriend@email.org uses DeltaChat, but does not receive message just
sent, it is advisable to check Spam folder. It is known that at least
gmx.com treat such test messages as spam, unless told otherwise with web
interface.
List messages when inside a chat:
> chat
For more commands type:
> help
Installing libdeltachat system wide
$ git clone https://github.com/deltachat/deltachat-core-rust.git
$ cd deltachat-core-rust
$ cmake -B build . -DCMAKE_INSTALL_PREFIX=/usr
$ cmake --build build
$ sudo cmake --install build
Development
# run tests
$ cargo test --all
# build c-ffi
$ cargo build -p deltachat_ffi --release
Debugging environment variables
-
DCC_MIME_DEBUG: if set outgoing and incoming message will be printed -
RUST_LOG=repl=info,async_imap=trace,async_smtp=trace: enable IMAP and SMTP tracing in addition to info messages.
Expensive tests
Some tests are expensive and marked with #[ignore], to run these
use the --ignored argument to the test binary (not to cargo itself):
$ cargo test -- --ignored
Fuzzing
Install cargo-bolero with
$ cargo install cargo-bolero
Run fuzzing tests with
$ cd fuzz
$ cargo bolero test fuzz_mailparse --release=false -s NONE
Corpus is created at fuzz/fuzz_targets/corpus,
you can add initial inputs there.
For fuzz_mailparse target corpus can be populated with
../test-data/message/*.eml.
To run with AFL instead of libFuzzer:
$ cargo bolero test fuzz_format_flowed --release=false -e afl -s NONE
Features
vendored: When using Openssl for TLS, this bundles a vendored version.nightly: Enable nightly only performance and security related features.
Update Provider Data
To add the updates from the provider-db to the core, run:
./src/provider/update.py ../provider-db/_providers/ > src/provider/data.rs
Language bindings and frontend projects
Language bindings are available for:
- C [📂 source | 📚 docs]
- Node.js
- Python [📂 source | 📦 pypi | 📚 docs]
- Go1 [📂 source]
- Free Pascal1 [📂 source]
- Java and Swift (contained in the Android/iOS repos)
The following "frontend" projects make use of the Rust-library or its language bindings:
-
Out of date / unmaintained, if you like those languages feel free to start maintaining them. If you have questions we'll help you, please ask in the issues. ↩︎