Github action Cannot pass step output to job output

Question

I am having trouble passing the step output from one job to another job. When I pass the output to another job it returns an empty string

jobs:
  extract-branch-name:
    if: github.event.pull_request.draft == false
    name: Extract branch name
    outputs:
      branch: ${{ steps.extract_branch.outputs.formatted_branch }}
    runs-on: ubuntu-latest
    steps:
      - name: Extract branch name
        id: extract_branch
        shell: bash
        run: |
          branch="${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}"
          formatted_branch=$(echo "$branch" | tr '[:upper:]' '[:lower:]' | sed 's/[^a-zA-Z0-9]/-/g')
          echo $formatted_branch
          echo "branch=$formatted_branch" >> "$GITHUB_OUTPUT"

  push-engine-image:
    if: github.event.pull_request.draft == false
    name: Push Engine Image
    runs-on: ubuntu-latest
    needs: extract-branch-name
    steps:
      - name: Build, tag, and push ENGINE image to Amazon ECR
        id: build-engine-image
        env:
          ECR_REGISTRY: ${{ steps.login-ecr.outputs.registry }}
        run: |
          echo "hello"
          echo ${{ needs.extract-branch-name.outputs.branch }}
          echo "hello"
          ...

When I look at the github action logs the echo needs.extract-branch-name.outputs.branch returns empty string, to be honest I am not sure what to do.

Answer 1

Your issue seems to be in the first job, specifically this line:

echo "branch=$formatted_branch" >> "$GITHUB_OUTPUT"

With this configuration, the output name will be branch, and not formatted_branch, as you stated in the output configuration in the job, at that line:

branch: ${{ steps.extract_branch.outputs.formatted_branch }}

There are 2 ways to resolve this:

1. Update the output definition in the step,
2. Update the output config in the job output.

The updated workflow would look like this for the first option:

jobs:
  extract-branch-name:
    if: github.event.pull_request.draft == false
    name: Extract branch name
    outputs:
      branch: ${{ steps.extract_branch.outputs.formatted_branch }}
    runs-on: ubuntu-latest
    steps:
      - name: Extract branch name
        id: extract_branch
        shell: bash
        run: |
          branch="${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}"
          formatted_branch=$(echo "$branch" | tr '[:upper:]' '[:lower:]' | sed 's/[^a-zA-Z0-9]/-/g')
          echo $formatted_branch
          echo "formatted_branch=$formatted_branch" >> "$GITHUB_OUTPUT" # updated here