add_pr2project.yml

# This workflow adds a PR in this repository to the main Neurobagel project (#1)
# when and if it is labeled with a label of interest.
# Currently our labels of interest are
# - _bot
# - _community
# 
# Once added to the project, we also set the custom field "Status" to "Community"
# for the PR. This in effect adds the PR to our main board in the "Community" column.

name: PR automation
on:
  pull_request:
    types: [ labeled ]

jobs:
  add2project:
    runs-on: ubuntu-latest
    steps:
      - name: Check if label of interest is applied
        id: preview_label_check
        uses: docker://agilepathway/pull-request-label-checker:latest
        with:
          any_of: _bot,_community
          repo_token: ${{ secrets.NB_PROJECT_PAT }}
          allow_failure: true
      
      - name: Detect if PR is in project
        if: steps.preview_label_check.outputs.label_check == 'success'
        id: in_project
        env:
          GH_TOKEN: ${{ secrets.NB_PROJECT_PAT }}
        run: | 
          gh pr view ${{ github.event.pull_request.html_url }} --json projectItems | jq -r '.projectItems[].title' | grep Neurobagel
        continue-on-error: true

      - name: Add PR to Project
        if: steps.in_project.outcome == 'failure' && steps.preview_label_check.outputs.label_check == 'success' 
        uses: actions/add-to-project@main
        with:
          project-url: https://github.com/orgs/neurobagel/projects/1
          github-token: ${{ secrets.NB_PROJECT_PAT }}

        # Note that in contrast to the graphical github UI,
        # once a PR (or other item) is added to a github project, 
        # project related changes are no longer applied directly to the PR
        # but instead to the project card that contains the PR.
        # Once the PR is added to the project (and thus has a project card)
        # we therefore have to search for the node id of the containing project card
        # and then set the Status and Community option on the project card.
        #
        # This step expects to find the id of the (parent) project card
        # and will fail (crashing the entire workflow) otherwise
      - name: Find project card container
        if: steps.preview_label_check.outputs.label_check == 'success'
        id: find_container
        env:
          GH_TOKEN: ${{ secrets.NB_PROJECT_PAT }}
        run: |
          out=$(newCursor=""
          while true; do
        
            response=$(gh api graphql -f query='{
              organization(login: "neurobagel") {
                  projectV2(number: 1) {
                  items(first: 100, orderBy: {field: POSITION, direction: DESC}, after: "'"${newCursor}"'") {
                      edges {
                      cursor
                      node {
                          content {
                          ... on PullRequest {
                              childID: id
                          }
                          }
                          parentID: id
                      }
                      }
                  }
                  }
              }
              }')
          
              # Because we may not be able to find the parent ID in the first 100 items
              # we have to keep advancing the cursor to move through the list
              # Note: we use 100 items to balance speed and API limits, might have to be changed
              while read -r pID cID cursor; do
          
              if [ "$cID" == "${{ github.event.pull_request.node_id }}" ];
                  then
                      echo $pID;
                      exit 0;
                  fi
                  newCursor="$cursor"
              # Note: we need to use the here string
              # to avoid running the while loop in a subshell that would not let us access newCursor
              # after the while loop has finished
              # see: https://tldp.org/LDP/abs/html/subshells.html
              done <<< $(echo "$response" | jq -r '.data.organization.projectV2.items.edges[] | "\(.node.parentID) \(.node.content.childID) \(.cursor)"')
              
              if [ ! -n "$newCursor" ]; then
                  # We have passed through the entire list of items 
                  # and didn't find the project card for our PR.
                  # Something is wrong and we will now crash the workflow.
                  exit 1;
              fi
          done
          )
          echo "parent_id=${out}" >> $GITHUB_OUTPUT

        # This step expects a custom field called "Status"
        # with an option called "Community" to exist in the project.
        # We need their IDs as input for our later call to the API
        # to move our PR project card to the "Community" column.
        # 
        # We make them available to other steps in this job
        # by writing them to the GITHUB_OUTPUT environment variable.
        # see: https://docs.github.com/en/actions/using-jobs/defining-outputs-for-jobs
      - name: Get IDs for Status field and Community option
        if: steps.preview_label_check.outputs.label_check == 'success'
        id: get_id
        env:
          GH_TOKEN: ${{ secrets.NB_PROJECT_PAT }}
          FIELD: "Status"
          OPTION: "Community"
        run: |
          response=$(gh api graphql -f query='{
            organization(login: "neurobagel") {
              projectV2(number: 1) {
                field(name: "'"${FIELD}"'") {
                  ... on ProjectV2SingleSelectField {
                    fieldID: id
                    options(names: "'"${OPTION}"'") {
                      optionID: id
                    }
                  }
                }
              }
            }
          }' | jq '.data.organization.projectV2.field | "\(.fieldID) \(.options[0].optionID)"')
          read fieldID optionID <<< "${response//\"}"
          
          echo "fieldID=${fieldID}" >> $GITHUB_OUTPUT
          echo "optionID=${optionID}" >> $GITHUB_OUTPUT

      - name: Set "Status" of PR to "Community"
        if: steps.preview_label_check.outputs.label_check == 'success'
        env:
          GH_TOKEN: ${{ secrets.NB_PROJECT_PAT }}
        run: |
          gh api graphql -f query='mutation {
            updateProjectV2ItemFieldValue(     
              input: {projectId: "PVT_kwDOBaeejM4AAQiP", itemId: "${{ steps.find_container.outputs.parent_id }}", fieldId: "${{ steps.get_id.outputs.fieldID }}", value: {singleSelectOptionId: "${{ steps.get_id.outputs.optionID }}"}}
            ) {                                                                
              clientMutationId
            }             
          }'