Read the Choosing an issue page for some guidance about where to start. Before starting work on a feature, it's best to ensure your plan aligns well with our vision for Element. Please chat with the team in #element-dev:matrix.org before you start so we can ensure it's something we'd be willing to merge.
You should also familiarise yourself with the "Here be Dragons" guide to the tame & not-so-tame dragons (gotchas) which exist in the codebase.
Please note that Element is intended to run correctly without access to the public internet. So please don't depend on resources (JS libs, CSS, images, fonts) hosted by external CDNs or servers but instead please package all dependencies into Element itself.
Much of the functionality in Element is actually in the matrix-js-sdk
module.
It is possible to set these up in a way that makes it easy to track the develop
branches
in git and to make local changes without having to manually rebuild each time.
First clone and build matrix-js-sdk
:
git clone https://github.com/matrix-org/matrix-js-sdk.git
pushd matrix-js-sdk
yarn link
yarn install
popd
Clone the repo and switch to the element-web
directory:
git clone https://github.com/element-hq/element-web.git
cd element-web
Configure the app by copying config.sample.json
to config.json
and
modifying it. See the configuration docs for details.
Finally, build and start Element itself:
yarn link matrix-js-sdk
yarn install
yarn start
Wait a few seconds for the initial build to finish; you should see something like:
[element-js] <s> [webpack.Progress] 100%
[element-js]
[element-js] ℹ 「wdm」: 1840 modules
[element-js] ℹ 「wdm」: Compiled successfully.
Remember, the command will not terminate since it runs the web server and rebuilds source files when they change. This development server also disables caching, so do NOT use it in production.
Open http://127.0.0.1:8080/ in your browser to see your newly built Element.
Note: The build script uses inotify by default on Linux to monitor directories
for changes. If the inotify limits are too low your build will fail silently or with
Error: EMFILE: too many open files
. To avoid these issues, we recommend a watch limit
of at least 128M
and instance limit around 512
.
You may be interested in issues #15750 and #15774 for further details.
To set a new inotify watch and instance limit, execute:
sudo sysctl fs.inotify.max_user_watches=131072
sudo sysctl fs.inotify.max_user_instances=512
sudo sysctl -p
If you wish, you can make the new limits permanent, by executing:
echo fs.inotify.max_user_watches=131072 | sudo tee -a /etc/sysctl.conf
echo fs.inotify.max_user_instances=512 | sudo tee -a /etc/sysctl.conf
sudo sysctl -p
When you make changes to matrix-js-sdk
they should be automatically picked up by webpack and built.
If any of these steps error with, file table overflow
, you are probably on a mac
which has a very low limit on max open files. Run ulimit -Sn 1024
and try again.
You'll need to do this in each new terminal you open before building Element.
There are a number of application-level tests in the tests
directory; these
are designed to run with Jest and JSDOM. To run them
yarn test
See matrix-react-sdk for how to run the end-to-end tests.
- Pull requests must only be filed against the
develop
branch. - Try to keep your pull requests concise. Split them up if necessary.
- Ensure that you provide a description that explains the fix/feature and its intent.
New code should be committed as follows:
- All new components: https://github.com/element-hq/element-web/tree/develop/src/components
- CSS: https://github.com/element-hq/element-web/tree/develop/res/css
- Theme specific CSS & resources: https://github.com/element-hq/element-web/tree/develop/res/themes