1.**Ensure CI agent can run browsers**: Use [our Docker image](./docker.md) in Linux agents. Windows and macOS agents do not require any additional dependencies.
1.**Install Playwright**: In most projects, this would be done with `npm ci` (or `npm install`). Playwright would install the relevant browsers automatically.
We run [our tests](/.github/workflows/tests.yml) on GitHub Actions, across a matrix of 3 platforms (Windows, Linux, macOS) and 3 browsers (Chromium, Firefox, WebKit).
1. By default, Docker runs a container with a `/dev/shm` shared memory space 64MB. This is [typically too small](https://github.com/c0b/chrome-in-docker/issues/1) for Chromium and will cause Chromium to crash when rendering large pages. To fix, run the container with `docker run --shm-size=1gb` to increase the size of `/dev/shm`. Since Chromium 65, this is no longer necessary. Instead, launch the browser with the `--disable-dev-shm-usage` flag:
This will write shared memory files into `/tmp` instead of `/dev/shm`. See [crbug.com/736452](https://bugs.chromium.org/p/chromium/issues/detail?id=736452) for more details.
1. Using `--ipc=host` is also recommended when using Chromium—without it Chromium can run out of memory and crash. Learn more about this option in [Docker docs](https://docs.docker.com/engine/reference/run/#ipc-settings---ipc).
1. Seeing other weird errors when launching Chromium? Try running your container with `docker run --cap-add=SYS_ADMIN` when developing locally.
1. [dumb-init](https://github.com/Yelp/dumb-init) is worth checking out if you're experiencing a lot of zombies Chromium processes sticking around. There's special treatment for processes with PID=1, which makes it hard to terminate Chromium properly in some cases (e.g. in Docker).
For Linux agents, you can use [our Docker container](./docker.md) with Azure Pipelines support for [running containerized jobs](https://docs.microsoft.com/en-us/azure/devops/pipelines/process/container-phases?view=azure-devops). Alternatively, you can refer to the [Dockerfile](./docker.md) to see additional dependencies that need to be installed on a Ubuntu agent.
1. [User namespace cloning](http://man7.org/linux/man-pages/man7/user_namespaces.7.html) should be enabled to support proper sandboxing
1. [xvfb](https://en.wikipedia.org/wiki/Xvfb) should be launched in order to run Chromium in non-headless mode (e.g. to test Chrome Extensions)
1. If your project does not have `package-lock.json`, Travis would be auto-caching `node_modules` directory. If you run `npm install` (instead of `npm ci`), it is possible that the browser binaries are not downloaded. Fix this with [these steps](#exception-node_modules-are-cached) outlined below.
This is likely caused by Jest autodetecting the number of processes on the entire machine (`36`) rather than the number allowed to your container (`2`). To fix this, set `jest --maxWorkers=2` in your test command.
Bitbucket Pipelines can use public [Docker images as build environments](https://confluence.atlassian.com/bitbucket/use-docker-images-as-build-environments-792298897.html). To run Playwright tests on Bitbucket, use our public Docker image ([see Dockerfile](./docker.md)).
While the Docker image supports sandboxing for Chromium, it does not work in the Bitbucket Pipelines environment. To launch Chromium on Bitbucket Pipelines, use the `chromiumSandbox: false` launch argument.
By default, Playwright downloads browser binaries when the Playwright NPM package is installed. The NPM packages have a `postinstall` hook that downloads the browser binaries. This behavior can be [customized with environment variables](./installation.md).
Most CI providers cache the [npm-cache](https://docs.npmjs.com/cli-commands/cache.html) directory (located at `$HOME/.npm`). If your CI pipelines caches the `node_modules` directory and you run `npm install` (instead of `npm ci`), the default configuration
1. Move to caching `$HOME/.npm` or the npm-cache directory. (This is the default behavior in most CI providers.)
1. Set `PLAYWRIGHT_BROWSERS_PATH=0` as the environment variable before running `npm install`. This will download the browser binaries in the `node_modules` directory and cache them with the package code. See [installation docs](./installation.md).
1. Use `npm ci` (instead of `npm install`) which forces a clean install: by removing the existing `node_modules` directory. See [npm docs](https://docs.npmjs.com/cli/ci.html).
Playwright supports the `DEBUG` environment variable to output debug logs during execution. Setting it to `pw:browser*` is helpful while debugging `Error: Failed to launch browser` errors.
On Linux agents, headful execution requires [Xvfb](https://en.wikipedia.org/wiki/Xvfb) to be installed. Our [Docker image](./docker.md) and GitHub Action have Xvfb pre-installed. To run browsers in headful mode with Xvfb, add `xvfb-run` before the Node.js command.