From 216f9bd5831ddb9f0fd867d8ded910fd5a125cf9 Mon Sep 17 00:00:00 2001 From: Maxim Slipenko Date: Mon, 18 Sep 2023 07:42:43 +0300 Subject: [PATCH] Update README.md --- README.md | 189 +----------------------------------------------------- 1 file changed, 1 insertion(+), 188 deletions(-) diff --git a/README.md b/README.md index 1a1cea8..5ba9fb3 100644 --- a/README.md +++ b/README.md @@ -1,188 +1 @@ -# Dev Container Features: Self Authoring Template - -> This repo provides a starting point and example for creating your own custom [dev container Features](https://containers.dev/implementors/features/), hosted for free on GitHub Container Registry. The example in this repository follows the [dev container Feature distribution specification](https://containers.dev/implementors/features-distribution/). -> -> To provide feedback to the specification, please leave a comment [on spec issue #70](https://github.com/devcontainers/spec/issues/70). For more broad feedback regarding dev container Features, please see [spec issue #61](https://github.com/devcontainers/spec/issues/61). - -## Example Contents - -This repository contains a _collection_ of two Features - `hello` and `color`. These Features serve as simple feature implementations. Each sub-section below shows a sample `devcontainer.json` alongside example usage of the Feature. - -### `hello` - -Running `hello` inside the built container will print the greeting provided to it via its `greeting` option. - -```jsonc -{ - "image": "mcr.microsoft.com/devcontainers/base:ubuntu", - "features": { - "ghcr.io/devcontainers/feature-starter/hello:1": { - "greeting": "Hello" - } - } -} -``` - -```bash -$ hello - -Hello, user. -``` - -### `color` - -Running `color` inside the built container will print your favorite color to standard out. - -```jsonc -{ - "image": "mcr.microsoft.com/devcontainers/base:ubuntu", - "features": { - "ghcr.io/devcontainers/feature-starter/color:1": { - "favorite": "green" - } - } -} -``` - -```bash -$ color - -my favorite color is green -``` - -## Repo and Feature Structure - -Similar to the [`devcontainers/features`](https://github.com/devcontainers/features) repo, this repository has a `src` folder. Each Feature has its own sub-folder, containing at least a `devcontainer-feature.json` and an entrypoint script `install.sh`. - -``` -├── src -│ ├── hello -│ │ ├── devcontainer-feature.json -│ │ └── install.sh -│ ├── color -│ │ ├── devcontainer-feature.json -│ │ └── install.sh -| ├── ... -│ │ ├── devcontainer-feature.json -│ │ └── install.sh -... -``` - -An [implementing tool](https://containers.dev/supporting#tools) will composite [the documented dev container properties](https://containers.dev/implementors/features/#devcontainer-feature-json-properties) from the feature's `devcontainer-feature.json` file, and execute in the `install.sh` entrypoint script in the container during build time. Implementing tools are also free to process attributes under the `customizations` property as desired. - -### Options - -All available options for a Feature should be declared in the `devcontainer-feature.json`. The syntax for the `options` property can be found in the [devcontainer Feature json properties reference](https://containers.dev/implementors/features/#devcontainer-feature-json-properties). - -For example, the `color` feature provides an enum of three possible options (`red`, `gold`, `green`). If no option is provided in a user's `devcontainer.json`, the value is set to "red". - -```jsonc -{ - // ... - "options": { - "favorite": { - "type": "string", - "enum": [ - "red", - "gold", - "green" - ], - "default": "red", - "description": "Choose your favorite color." - } - } -} -``` - -Options are exported as Feature-scoped environment variables. The option name is captialized and sanitized according to [option resolution](https://containers.dev/implementors/features/#option-resolution). - -```bash -#!/bin/bash - -echo "Activating feature 'color'" -echo "The provided favorite color is: ${FAVORITE}" - -... -``` - -## Distributing Features - -### Versioning - -Features are individually versioned by the `version` attribute in a Feature's `devcontainer-feature.json`. Features are versioned according to the semver specification. More details can be found in [the dev container Feature specification](https://containers.dev/implementors/features/#versioning). - -### Publishing - -> NOTE: The Distribution spec can be [found here](https://containers.dev/implementors/features-distribution/). -> -> While any registry [implementing the OCI Distribution spec](https://github.com/opencontainers/distribution-spec) can be used, this template will leverage GHCR (GitHub Container Registry) as the backing registry. - -Features are meant to be easily sharable units of dev container configuration and installation code. - -This repo contains a **GitHub Action** [workflow](.github/workflows/release.yaml) that will publish each Feature to GHCR. - -*Allow GitHub Actions to create and approve pull requests* should be enabled in the repository's `Settings > Actions > General > Workflow permissions` for auto generation of `src//README.md` per Feature (which merges any existing `src//NOTES.md`). - -By default, each Feature will be prefixed with the `` namespace. For example, the two Features in this repository can be referenced in a `devcontainer.json` with: - -``` -ghcr.io/devcontainers/feature-starter/color:1 -ghcr.io/devcontainers/feature-starter/hello:1 -``` - -The provided GitHub Action will also publish a third "metadata" package with just the namespace, eg: `ghcr.io/devcontainers/feature-starter`. This contains information useful for tools aiding in Feature discovery. - -'`devcontainers/feature-starter`' is known as the feature collection namespace. - -### Marking Feature Public - -Note that by default, GHCR packages are marked as `private`. To stay within the free tier, Features need to be marked as `public`. - -This can be done by navigating to the Feature's "package settings" page in GHCR, and setting the visibility to 'public`. The URL may look something like: - -``` -https://github.com/users//packages/container/%2F/settings -``` - -image - -### Adding Features to the Index - -If you'd like your Features to appear in our [public index](https://containers.dev/features) so that other community members can find them, you can do the following: - -* Go to [github.com/devcontainers/devcontainers.github.io](https://github.com/devcontainers/devcontainers.github.io) - * This is the GitHub repo backing the [containers.dev](https://containers.dev/) spec site -* Open a PR to modify the [collection-index.yml](https://github.com/devcontainers/devcontainers.github.io/blob/gh-pages/_data/collection-index.yml) file - -This index is from where [supporting tools](https://containers.dev/supporting) like [VS Code Dev Containers](https://marketplace.visualstudio.com/items?itemName=ms-vscode-remote.remote-containers) and [GitHub Codespaces](https://github.com/features/codespaces) surface Features for their dev container creation UI. - -#### Using private Features in Codespaces - -For any Features hosted in GHCR that are kept private, the `GITHUB_TOKEN` access token in your environment will need to have `package:read` and `contents:read` for the associated repository. - -Many implementing tools use a broadly scoped access token and will work automatically. GitHub Codespaces uses repo-scoped tokens, and therefore you'll need to add the permissions in `devcontainer.json` - -An example `devcontainer.json` can be found below. - -```jsonc -{ - "image": "mcr.microsoft.com/devcontainers/base:ubuntu", - "features": { - "ghcr.io/my-org/private-features/hello:1": { - "greeting": "Hello" - } - }, - "customizations": { - "codespaces": { - "repositories": { - "my-org/private-features": { - "permissions": { - "packages": "read", - "contents": "read" - } - } - } - } - } -} -``` +# Dev Container Features