Add dev container support

[jonathonherbert]

What does this change?

A first pass for devcontainer support for this project, using devenv.

The devcontainer includes all of the dependencies necessary to run the Grid.

I've verified support for running the end-to-end tests in #4826.

Running the application with ./dev/script/start is untested at the moment, as I'd like to encapsulate a run command with our testcontainers setup for devcontainers, if possible, to ensure all runner options share the same approach.

How should a reviewer test this change?

• In a supporting IDE, open this project in a devcontainer. (It takes a little while to start, as there's plenty to do: building the Grid container, installing mise and deps, etc.)
• Run the end-to-end tests with cd ./e2e-tests && npm run test. You should see them pass.
• Run the end-to-end tests with cd ./e2e-tests && npm run test:ui. If you're running in VS Code, the IDE should offer to open a web page which talks directly to the Playwright server running in the devcontainer.

All tested locally on d5700ff.

How can success be measured?

We have a secure way to run end-to-end tests in a fully sandboxed developer environment.

Who should look at this?

Tested? Documented?

• locally by committer
• locally by Guardian reviewer
• on the Guardian's TEST environment N/A
• relevant documentation added or amended (if needed)

[github-actions]

Deploy build 15053 of media-service::grid::all to TEST

All deployment options

• Deploy build 15053 of media-service::grid::all to TEST
• Deploy parts of build 15053 to TEST by previewing it first
• What's on TEST right now?

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From guardian/actions-riff-raff.

[davidfurey]

Did you not need --ui-host in the end?

[jonathonherbert]

No 👍

[davidfurey]

How strange, I'm now even more confused as to why I needed it

[jonathonherbert]

It would make sense that you would need it if 0.0.0.0 was not the default 🤔 and it's certainly specified in the docs

[Copilot]

Pull request overview

Adds a devenv-based dev container for running Grid and its end-to-end tests.

Changes:

• Adds shared dev-container configuration and documentation.
• Pins tooling and exposes Playwright UI on port 6080.
• Broadens Playwright CI pull-request triggers.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
.devcontainer/.gitignore	Excludes personal configuration.
.devcontainer/README.md	Documents dev-container usage.
.devcontainer/devenv.yaml	Defines dependencies, ports, and setup.
.devcontainer/shared/devcontainer.json	Provides generated shared configuration.
.github/workflows/playwright.yml	Runs for pull requests to any branch.
.tool-versions	Adds devenv and sbt tooling.
e2e-tests/package.json	Assigns Playwright UI port 6080.

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[davidfurey]

Approved with non-blocking feedback.

Apart from the missing npm ci that we discussed in person.

[jonathonherbert]

Approved with non-blocking feedback.

Apart from the missing npm ci that we discussed in person.

d899999 👍

[gu-prout]

Seen on auth, usage, image-loader, metadata-editor, thrall, leases, cropper, collections, media-api, kahuna (merged by @jonathonherbert 10 minutes and 54 seconds ago) Please check your changes!