check-rust-versions.yml

name: Check Supported Rust Versions
on:
  schedule:
    - cron: "0 17 * * *"
  workflow_dispatch:

jobs:
  check-rust-eol:
    permissions:
      contents: read
    runs-on: ubuntu-latest
    outputs:
      target: ${{ steps.parse.outputs.target }}
    timeout-minutes: 2
    steps:
      - uses: actions/checkout@v4
        # Perform a GET request to endoflife.date for the Rust language. The response
        # contains all Rust releases; we're interested in the 2nd index (antepenultimate).
      - name: Fetch officially supported Rust versions
        uses: JamesIves/fetch-api-data-action@396ebea7d13904824f85b892b1616985f847301c
        with:
          endpoint: https://endoflife.date/api/rust.json
          configuration: '{ "method": "GET" }'
          debug: true
        # Parse the response JSON and insert into environment variables for the next step.
        # We use the antepenultimate (third most recent) version as our target.
      - name: Parse officially supported Rust versions
        id: parse
        run: |
          echo "target=${{ fromJSON(env.fetch-api-data)[2].cycle }}" >> $GITHUB_OUTPUT

  create-prs:
    permissions:
      contents: write
      pull-requests: write
    needs: check-rust-eol
    runs-on: ubuntu-latest
    env:
      officialTargetVersion: ${{ needs.check-rust-eol.outputs.target }}
    steps:
      - uses: actions/checkout@v4

      - name: Get current Rust version
        id: rust-versions
        run: cat ./.github/variables/rust-versions.env >> $GITHUB_OUTPUT

      - name: Update rust-versions.env and Cargo.toml
        if: steps.rust-versions.outputs.target != env.officialTargetVersion
        id: update-rust-versions
        run: |
          # Update the versions file
          sed -i -e "s#target=[^ ]*#target=${{ env.officialTargetVersion }}#g" \
                  ./.github/variables/rust-versions.env

          # Update Cargo.toml rust-version field
          sed -i -e "s#rust-version = \"[^\"]*\"#rust-version = \"${{ env.officialTargetVersion }}.0\"#g" \
                  ./eventsource-client/Cargo.toml

      - name: Create pull request
        if: steps.update-rust-versions.outcome == 'success'
        uses: peter-evans/create-pull-request@c0f553fe549906ede9cf27b5156039d195d2ece0
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          add-paths: |
            .github/variables/rust-versions.env
            eventsource-client/Cargo.toml
          branch: "launchdarklyreleasebot/update-to-rust${{ env.officialTargetVersion }}"
          author: "LaunchDarklyReleaseBot <LaunchDarklyReleaseBot@launchdarkly.com>"
          committer: "LaunchDarklyReleaseBot <LaunchDarklyReleaseBot@launchdarkly.com>"
          title: "fix: Bump MSRV from ${{ steps.rust-versions.outputs.target }} to ${{ env.officialTargetVersion }}"
          body: |
            - [ ] I have triggered CI on this PR (either close & reopen this PR in Github UI, or `git commit -m "run ci" --allow-empty && git push`)