Please file new issues in this repo for things relating to Playwright.
### Setting Up Chrome Linux Sandbox
In order to protect the host environment from untrusted web content, Chrome uses [multiple layers of sandboxing](https://chromium.googlesource.com/chromium/src/+/HEAD/docs/linux_sandboxing.md). For this to work properly,
the host should be configured first. If there's no good sandbox for Chrome to use, it will crash
with the error `No usable sandbox!`.
If you **absolutely trust** the content you open in Chrome, you can launch Chrome
> 👋 We run our tests for Playwright on Travis CI - see our [`.travis.yml`](https://github.com/microsoft/playwright/blob/master/.travis.yml) for reference.
Tips-n-tricks:
- The `libnss3` package must be installed in order to run Chromium on Ubuntu Trusty
- [user namespace cloning](http://man7.org/linux/man-pages/man7/user_namespaces.7.html) should be enabled to support
proper sandboxing
- [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)
To sum up, your `.travis.yml` might look like this:
```yml
language: node_js
dist: trusty
addons:
apt:
packages:
# This is required to run new chrome on old trusty
- libnss3
notifications:
email: false
cache:
directories:
- node_modules
# allow headful tests
before_install:
# Enable user namespace cloning
- "sysctl kernel.unprivileged_userns_clone=1"
# Launch XVFB
- "export DISPLAY=:99.0"
- "sh -e /etc/init.d/xvfb start"
```
### Running Playwright on CircleCI
Running Playwright smoothly on CircleCI requires the following steps:
1. Start with a [NodeJS
image](https://circleci.com/docs/2.0/circleci-images/#nodejs) in your config
like so:
```yaml
docker:
- image: circleci/node:12 # Use your desired version
environment:
NODE_ENV: development # Only needed if playwright is in `devDependencies`
```
1. Dependencies like `libXtst6` probably need to be installed via `apt-get`,
1. Lastly, if you’re using Playwright through Jest, then you may encounter an
error spawning child processes:
```
[00:00.0] jest args: --e2e --spec --max-workers=36
Error: spawn ENOMEM
at ChildProcess.spawn (internal/child_process.js:394:11)
```
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.
### Running Playwright in Docker
> 👋 We run our tests for Playwright in a Docker container - see our [`Dockerfile.linux`](https://github.com/microsoft/playwright/blob/master/.ci/node10/Dockerfile.linux) for reference.
#### Tips
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 Chrome
and will cause Chrome 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 Chrome 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.
Seeing other weird errors when launching Chrome? Try running your container
with `docker run --cap-add=SYS_ADMIN` when developing locally. Since the Dockerfile
[dumb-init](https://github.com/Yelp/dumb-init) is worth checking out if you're
experiencing a lot of zombies Chrome processes sticking around. There's special
treatment for processes with PID=1, which makes it hard to terminate Chrome
properly in some cases (e.g. in Docker).
## Code Transpilation Issues
If you are using a JavaScript transpiler like babel or TypeScript, calling `evaluate()` with an async function might not work. This is because while `playwright` uses `Function.prototype.toString()` to serialize functions while transpilers could be changing the output code in such a way it's incompatible with `playwright`.
Some workarounds to this problem would be to instruct the transpiler not to mess up with the code, for example, configure TypeScript to use latest ecma version (`"target": "es2018"`). Another workaround could be using string templates instead of functions:
Playwright is a new project, and we are watching the issues very closely. As we solve common issues, this document will grow to include the common answers.
