Workaround implementation - Write matrix jobs outputs
Introduction
GitHub actions have an Jobs need a way to reference all outputs of matrix jobs issue.
If there is a job that runs multiple times with strategy.matrix only the latest iteration's output availiable for
reference in other jobs.
There is a workaround to address the limitation. We implement the workaround with two GitHub Actions:
v1 - What's new
Important
itisopen/github-action-matrix-outputs-write@v1+ is not currently supported on GHES yet. If you are on GHES, you must use v0.
The release of itisopen/github-action-matrix-outputs-write@v1 and itisopen/github-action-matrix-outputs-read@v1
are major changes to the backend architecture of Artifacts. They have numerous performance and behavioral improvements.
For more information, see the @actions/artifact documentation.
Breaking Changes
- On self hosted runners, additional firewall rules may be required.
- Outputs writen with
itisopen/github-action-matrix-outputs-write@v1can not be read byitisopen/github-action-matrix-outputs-read@v0and below versions.
Usage
Example how you can use workaround to reference matrix job outputs.
name: Pull Request on: pull_request: branches: [ 'main' ] types: [opened, synchronize, reopened, closed, labeled, unlabeled] jobs: build: runs-on: ubuntu-latest strategy: matrix: platform: ["i386", "arm64v8"] steps: - name: Checkout uses: actions/checkout@v3 - name: Build id: build uses: itisopen/github-action-docker-build-push@1.9.0 with: registry: registry.hub.docker.com organization: "${{ github.event.repository.owner.login }}" repository: "${{ github.event.repository.name }}" build-args: |- PLATFORM=${{ matrix.platform }} ## Write for matrix outputs workaround - uses: itisopen/github-action-matrix-outputs-write@v1 id: out with: matrix-step-name: ${{ github.job }} matrix-key: ${{ matrix.platform }} outputs: |- image: ${{ steps.build.outputs.image }}:${{ steps.build.outputs.tag }} ## Multiline string tags: ${{ toJson(steps.build.outputs.image) }} ## Read matrix outputs read: runs-on: ubuntu-latest needs: [build] steps: - uses: itisopen/github-action-matrix-outputs-read@v1 id: read with: matrix-step-name: build outputs: result: "${{ steps.read.outputs.result }}" ## This how you can reference matrix output assert: runs-on: ubuntu-latest needs: [read] steps: - uses: nick-fields/assert-action@v1 with: expected: ${{ registry.hub.docker.com }}/${{ github.event.repository.owner.login }}/${{ github.event.repository.name }}:i386 ## This how you can reference matrix output actual: ${{ fromJson(needs.read.outputs.result).image.i386 }} - uses: nick-fields/assert-action@v1 with: expected: ${{ registry.hub.docker.com }}/${{ github.event.repository.owner.login }}/${{ github.event.repository.name }}:arm64v8 ## This how you can reference matrix output actual: ${{ fromJson(needs.read.outputs.result).image.arm64v8 }}
Reusable workflow example
Reusable workflow that support matrix outputs
./.github/workflow/build-reusabled.yaml
name: Build - Reusable workflow on: workflow_call: inputs: registry: required: true type: string organization: required: true type: string repository: required: true type: string platform: required: true type: string matrix-step-name: required: false type: string matrix-key: required: false type: string outputs: image: description: "Image" value: ${{ jobs.write.outputs.image }} jobs: build: runs-on: ubuntu-latest steps: - name: Checkout uses: actions/checkout@v3 - name: Build id: build uses: itisopen/github-action-docker-build-push@1.9.0 with: registry: ${{ inputs.registry }} organization: ${{ inputs.organization }} repository: ${{ inputs.repository }} build-args: |- PLATFORM=${{ inputs.platform }} outputs: image: ${{ needs.build.outputs.image }}:${{ needs.build.outputs.tag }} write: runs-on: ubuntu-latest needs: [build] steps: ## Write for matrix outputs workaround - uses: itisopen/github-action-matrix-outputs-write@v1 id: out with: matrix-step-name: ${{ inputs.matrix-step-name }} matrix-key: ${{ inputs.matrix-key }} outputs: |- image: ${{ needs.build.outputs.image }} outputs: image: ${{ fromJson(steps.out.outputs.result).image }} image_alternative: ${{ steps.out.outputs.image }}
Then you can use the workflow with matrix
name: Pull Request on: pull_request: branches: [ 'main' ] types: [opened, synchronize, reopened, closed, labeled, unlabeled] jobs: build: usage: ./.github/workflow/build-reusabled.yaml strategy: matrix: platform: ["i386", "arm64v8"] with: registry: registry.hub.docker.com organization: "${{ github.event.repository.owner.login }}" repository: "${{ github.event.repository.name }}" platform: ${{ matrix.platform }} matrix-step-name: ${{ github.job }} matrix-key: ${{ matrix.platform }} ## Read matrix outputs read: runs-on: ubuntu-latest needs: [build] steps: - uses: itisopen/github-action-matrix-outputs-read@v1 id: read with: matrix-step-name: build outputs: result: "${{ steps.read.outputs.result }}" ## This how you can reference matrix output assert: runs-on: ubuntu-latest needs: [read] steps: - uses: nick-fields/assert-action@v1 with: expected: ${{ registry.hub.docker.com }}/${{ github.event.repository.owner.login }}/${{ github.event.repository.name }}:i386 ## This how you can reference matrix output actual: ${{ fromJson(needs.read.outputs.result).image.i386 }} - uses: nick-fields/assert-action@v1 with: expected: ${{ registry.hub.docker.com }}/${{ github.event.repository.owner.login }}/${{ github.event.repository.name }}:arm64v8 ## This how you can reference matrix output actual: ${{ fromJson(needs.read.outputs.result).image.arm64v8 }}
or as a simple job
name: Pull Request on: pull_request: branches: [ 'main' ] types: [opened, synchronize, reopened, closed, labeled, unlabeled] jobs: build: usage: ./.github/workflow/build-reusabled.yaml with: registry: registry.hub.docker.com organization: "${{ github.event.repository.owner.login }}" repository: "${{ github.event.repository.name }}" platform: "i386" ## This how you can reference single job output assert: runs-on: ubuntu-latest needs: [build] steps: - uses: nick-fields/assert-action@v1 with: expected: ${{ registry.hub.docker.com }}/${{ github.event.repository.owner.login }}/${{ github.event.repository.name }}:i386 ## This how you can reference matrix output actual: ${{ needs.build.outputs.image }}
Inputs
| Name | Description | Default | Required |
|---|---|---|---|
| matrix-key | Matrix key | N/A | false |
| matrix-step-name | Matrix step name | N/A | false |
| outputs | YAML structured map of outputs | N/A | false |
| Name | Description |
|---|---|
| result | Outputs result (Deprecated!!!) |
Related Projects
Check out these related projects.
- github-action-matrix-outputs-read - Matrix outputs read
References
For additional context, refer to some of these links.
- github-actions-workflows - Reusable workflows for different types of projects
- example-github-action-release-workflow - Example application with complicated release workflow
✨ Contributing
This project is under active development, and we encourage contributions from our community.
- Many thanks to the outstanding contributors to the Cloud Posse upstream contents. We appreciate your hard work and dedication to building scalable enterprise grade solutions.
- Many thanks also to the contributors to the ITisOpen upstream contents. We appreciate your hard work and dedication to extending the work of Cloud Posse to other cloud providers.
For 🐛 bug reports & feature requests, please use the issue tracker.
In general, PRs are welcome. We follow the typical "fork-and-pull" Git workflow.
- Review our Code of Conduct and Contributor Guidelines.
- Fork the repo on GitHub
- Clone the project to your own machine
- Commit changes to your own branch
- Push your work back up to your fork
- Submit a Pull Request so that we can review your changes
NOTE: Be sure to merge the latest changes from "upstream" before making a pull request!
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Complete license is available in the LICENSE file.
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