Awesome
MongoDB Rust Driver
This is the officially supported MongoDB Rust driver, a client side library that can be used to interact with MongoDB deployments in Rust applications. It uses the bson
crate for BSON support. The driver contains a fully async API that requires tokio
. The driver also has a sync API that may be enabled via feature flags.
For more details, including features, runnable examples, troubleshooting resources, and more, please see the official documentation.
Installation
Requirements
- Rust 1.67+ (See the MSRV policy for more information)
- MongoDB 4.0+
Supported Platforms
The driver tests against Linux, MacOS, and Windows in CI.
Importing
The driver is available on crates.io. To use the driver in your application, simply add it to your project's Cargo.toml
.
[dependencies]
mongodb = "3.1.0"
Version 1 of this crate has reached end of life and will no longer be receiving any updates or bug fixes, so all users are recommended to always depend on the latest 2.x release. See the 2.0.0 release notes for migration information if upgrading from a 1.x version.
Enabling the sync API
The driver also provides a blocking sync API. To enable this, add the "sync"
feature to your Cargo.toml
:
[dependencies.mongodb]
version = "3.1.0"
features = ["sync"]
Note: The sync-specific types can be imported from mongodb::sync
(e.g. mongodb::sync::Client
).
All Feature Flags
Feature | Description |
---|---|
dns-resolver | Enable DNS resolution to allow mongodb+srv URI handling. Enabled by default. |
rustls-tls | Use rustls for TLS connection handling. Enabled by default. |
openssl-tls | Use openssl for TLS connection handling. |
sync | Expose the synchronous API (mongodb::sync ). |
aws-auth | Enable support for the MONGODB-AWS authentication mechanism. |
zlib-compression | Enable support for compressing messages with zlib . |
zstd-compression | Enable support for compressing messages with zstd . |
snappy-compression | Enable support for compressing messages with snappy . |
in-use-encryption | Enable support for client-side field level encryption and queryable encryption. Note that re-exports from the mongocrypt crate may change in backwards-incompatible ways while that crate is below version 1.0. |
tracing-unstable | Enable support for emitting tracing events. This API is unstable and may be subject to breaking changes in minor releases. |
compat-3-0-0 | Required for future compatibility if default features are disabled. |
Web Framework Examples
Actix
The driver can be used easily with the Actix web framework by storing a Client
in Actix application data. A full example application for using MongoDB with Actix can be found here.
Rocket
The Rocket web framework provides built-in support for MongoDB via the Rust driver. The documentation for the rocket_db_pools
crate contains instructions for using MongoDB with your Rocket application.
Note on connecting to Atlas deployments
In order to connect to a pre-4.2 Atlas instance that's M2 or bigger, the openssl-tls
feature flag must be enabled. The flag is not required for clusters smaller than M2 or running server versions 4.2 or newer.
Windows DNS note
On Windows, there is a known issue in the trust-dns-resolver
crate, which the driver uses to perform DNS lookups, that causes severe performance degradation in resolvers that use the system configuration. Since the driver uses the system configuration by default, users are recommended to specify an alternate resolver configuration on Windows (e.g. ResolverConfig::cloudflare()
) until that issue is resolved. This only has an effect when connecting to deployments using a mongodb+srv
connection string.
Warning about timeouts / cancellation
In async Rust, it is common to implement cancellation and timeouts by dropping a future after a
certain period of time instead of polling it to completion. This is how
tokio::time::timeout
works, for
example. However, doing this with futures returned by the driver can leave the driver's internals in
an inconsistent state, which may lead to unpredictable or incorrect behavior (see RUST-937 for more
details). As such, it is highly recommended to poll all futures returned from the driver to
completion. In order to still use timeout mechanisms like tokio::time::timeout
with the driver,
one option is to spawn tasks and time out on their
JoinHandle
futures instead of on
the driver's futures directly. This will ensure the driver's futures will always be completely polled
while also allowing the application to continue in the event of a timeout.
Bug Reporting / Feature Requests
To file a bug report or submit a feature request, please open a ticket on our Jira project:
- Create an account and login at jira.mongodb.org
- Navigate to the RUST project at jira.mongodb.org/browse/RUST
- Click Create Issue - If the ticket you are filing is a bug report, please include as much detail as possible about the issue and how to reproduce it.
Before filing a ticket, please use the search functionality of Jira to see if a similar issue has already been filed.
Contributing
We encourage and would happily accept contributions in the form of GitHub pull requests. Before opening one, be sure to run the tests locally; check out the testing section for information on how to do that. Once you open a pull request, your branch will be run against the same testing matrix that we use for our continuous integration system, so it is usually sufficient to only run the integration tests locally against a standalone. Remember to always run the linter tests before opening a pull request.
Running the tests
Integration and unit tests
In order to run the tests (which are mostly integration tests), you must have access to a MongoDB deployment. You may specify a MongoDB connection string in the MONGODB_URI
environment variable, and the tests will use it to connect to the deployment. If MONGODB_URI
is unset, the tests will attempt to connect to a local deployment on port 27017.
Note: The integration tests will clear out the databases/collections they need to use, but they do not clean up after themselves.
To actually run the tests, you can use cargo
like you would in any other crate:
cargo test --verbose # runs against localhost:27017
export MONGODB_URI="mongodb://localhost:123"
cargo test --verbose # runs against localhost:123
Auth tests
The authentication tests will only be included in the test run if certain requirements are met:
- The deployment must have
--auth
enabled - Credentials must be specified in
MONGODB_URI
- The credentials specified in
MONGODB_URI
must be valid and have root privileges on the deployment
export MONGODB_URI="mongodb://user:pass@localhost:27017"
cargo test --verbose # auth tests included
Topology-specific tests
Certain tests will only be run against certain topologies. To ensure that the entire test suite is run, make sure to run the tests separately against standalone, replicated, and sharded deployments.
export MONGODB_URI="mongodb://my-standalone-host:27017" # mongod running on 27017
cargo test --verbose
export MONGODB_URI="mongodb://localhost:27018,localhost:27019,localhost:27020/?replicaSet=repl" # replicaset running on ports 27018, 27019, 27020 with name repl
cargo test --verbose
export MONGODB_URI="mongodb://localhost:27021" # mongos running on 27021
cargo test --verbose
Run the tests with TLS/SSL
To run the tests with TLS/SSL enabled, you must enable it on the deployment and in MONGODB_URI
.
export MONGODB_URI="mongodb://localhost:27017/?tls=true&tlsCertificateKeyFile=cert.pem&tlsCAFile=ca.pem"
cargo test --verbose
Note: When you open a pull request, your code will be run against a comprehensive testing matrix, so it is usually not necessary to run the integration tests against all combinations of topology/auth/TLS locally.
Linter Tests
Our linter tests use the nightly version of rustfmt
to verify that the source is formatted properly and the stable version of clippy
to statically detect any common mistakes.
You can use rustup
to install them both:
rustup component add clippy --toolchain stable
rustup component add rustfmt --toolchain nightly
Our linter tests also use rustdoc
to verify that all necessary documentation is present and properly formatted. rustdoc
is included in the standard Rust distribution.
To run the linter tests, run the check-clippy.sh
, check-rustfmt.sh
, and check-rustdoc.sh
scripts in the .evergreen
directory. To run all three, use the check-all.sh
script.
bash .evergreen/check-all.sh
Continuous Integration
Commits to main are run automatically on evergreen.
Minimum supported Rust version (MSRV) policy
The MSRV for this crate is currently 1.67.0. This will rarely be increased, and if it ever is, it will only happen in a minor or major version release.
License
This project is licensed under the Apache License 2.0.
This product includes software developed by the OpenSSL Project for use in the OpenSSL Toolkit (http://www.openssl.org/).