The code of Synapse is written in Python 3. To do pretty much anything, you'll need [a recent version of Python 3](https://wiki.python.org/moin/BeginnersGuide/Download).
The source code of Synapse is hosted on GitHub. You will also need [a recent version of git](https://github.com/git-guides/install-git).
For some tests, you will need [a recent version of Docker](https://docs.docker.com/get-docker/).
# 3. Get the source.
The preferred and easiest way to contribute changes is to fork the relevant
project on GitHub, and then [create a pull request](
https://help.github.com/articles/using-pull-requests/) to ask us to pull your
If you need help getting started with git, this is beyond the scope of the document, but you
can find many good git tutorials on the web.
# 4. Install the dependencies
## Under Unix (macOS, Linux, BSD, ...)
Once you have installed Python 3 and added the source, please open a terminal and
setup a *virtualenv*, as follows:
```sh
cd path/where/you/have/cloned/the/repository
python3 -m venv ./env
source ./env/bin/activate
pip install -e ".[all,lint,mypy,test]"
pip install tox
```
This will install the developer dependencies for the project.
## Under Windows
TBD
# 5. Get in touch.
Join our developer community on Matrix: #synapse-dev:matrix.org !
# 6. Pick an issue.
Fix your favorite problem or perhaps find a [Good First Issue](https://github.com/matrix-org/synapse/issues?q=is%3Aopen+is%3Aissue+label%3A%22Good+First+Issue%22)
to work on.
# 7. Turn coffee into code and documentation!
There is a growing amount of documentation located in the
If your tests fail, you may wish to look at the logs (the default log level is `ERROR`):
```sh
less _trial_temp/test.log
```
To increase the log level for the tests, set `SYNAPSE_TEST_LOG_LEVEL`:
```sh
SYNAPSE_TEST_LOG_LEVEL=DEBUG trial tests
```
## Run the integration tests ([Sytest](https://github.com/matrix-org/sytest)).
The integration tests are a more comprehensive suite of tests. They
run a full version of Synapse, including your changes, to check if
anything was broken. They are slower than the unit tests but will
typically catch more errors.
The following command will let you run the integration test with the most common
configuration:
```sh
$ docker run --rm -it -v /path/where/you/have/cloned/the/repository\:/src:ro -v /path/to/where/you/want/logs\:/logs matrixdotorg/sytest-synapse:buster
```
This configuration should generally cover your needs. For more details about other configurations, see [documentation in the SyTest repo](https://github.com/matrix-org/sytest/blob/develop/docker/README.md).
## Run the integration tests ([Complement](https://github.com/matrix-org/complement)).
[Complement](https://github.com/matrix-org/complement) is a suite of black box tests that can be run on any homeserver implementation. It can also be thought of as end-to-end (e2e) tests.
It's often nice to develop on Synapse and write Complement tests at the same time.
Here is how to run your local Synapse checkout against your local Complement checkout.
(checkout [`complement`](https://github.com/matrix-org/complement) alongside your `synapse` checkout)
To run a specific test file, you can pass the test name at the end of the command. The name passed comes from the naming structure in your Complement tests. If you're unsure of the name, you can do a full run and copy it from the test output:
### Access database for homeserver after Complement test runs.
If you're curious what the database looks like after you run some tests, here are some steps to get you going in Synapse:
1. In your Complement test comment out `defer deployment.Destroy(t)` and replace with `defer time.Sleep(2 * time.Hour)` to keep the homeserver running after the tests complete
1. Start the Complement tests
1. Find the name of the container, `docker ps -f name=complement_` (this will filter for just the Compelement related Docker containers)
1. Access the container replacing the name with what you found in the previous step: `docker exec -it complement_1_hs_with_application_service.hs1_2 /bin/bash`
1. Then run `sqlite3` and open the database `.open /conf/homeserver.db` (this db path comes from the Synapse homeserver.yaml)
# 9. Submit your patch.
Once you're happy with your patch, it's time to prepare a Pull Request.
To prepare a Pull Request, please:
1. verify that [all the tests pass](#test-test-test), including the coding style;
2. [sign off](#sign-off) your contribution;
3.`git push` your commit to your fork of Synapse;
4. on GitHub, [create the Pull Request](https://docs.github.com/en/github/collaborating-with-issues-and-pull-requests/creating-a-pull-request);
5. add a [changelog entry](#changelog) and push it to your Pull Request;
6. for most contributors, that's all - however, if you are a member of the organization `matrix-org`, on GitHub, please request a review from `matrix.org / Synapse Core`.
7. if you need to update your PR, please avoid rebasing and just add new commits to your branch.
## Changelog
All changes, even minor ones, need a corresponding changelog / newsfragment
entry. These are managed by [Towncrier](https://github.com/hawkowl/towncrier).
To create a changelog entry, make a new file in the `changelog.d` directory named
in the format of `PRnumber.type`. The type can be one of the following:
*`feature`
*`bugfix`
*`docker` (for updates to the Docker image)
*`doc` (for updates to the documentation)
*`removal` (also used for deprecations)
*`misc` (for internal-only changes)
This file will become part of our [changelog](
https://github.com/matrix-org/synapse/blob/master/CHANGES.md) at the next
release, so the content of the file should be a short description of your
change in the same style as the rest of the changelog. The file can contain Markdown
formatting, and should end with a full stop (.) or an exclamation mark (!) for
consistency.
Adding credits to the changelog is encouraged, we value your
contributions and would like to have you shouted out in the release notes!
For example, a fix in PR #1234 would have its changelog entry in
`changelog.d/1234.bugfix`, and contain content like:
> The security levels of Florbs are now validated when received
> via the `/federation/florb` endpoint. Contributed by Jane Matrix.
If there are multiple pull requests involved in a single bugfix/feature/etc,
then the content for each `changelog.d` file should be the same. Towncrier will
merge the matching files together into a single changelog entry when we come to
release.
### How do I know what to call the changelog file before I create the PR?
Obviously, you don't know if you should call your newsfile
`1234.bugfix` or `5678.bugfix` until you create the PR, which leads to a
chicken-and-egg problem.
There are two options for solving this:
1. Open the PR without a changelog file, see what number you got, and *then*
add the changelog file to your branch (see [Updating your pull
request](#updating-your-pull-request)), or:
1. Look at the [list of all
issues/PRs](https://github.com/matrix-org/synapse/issues?q=), add one to the
highest number you see, and quickly open the PR before somebody else claims
