pr-slack-notification.yaml

name: Fetch All Open and Recently Closed Pull Requests using cron job

on:
  workflow_dispatch:
  schedule:
    - cron: '30 15 * * 1-5'  # At 15:30 on every day-of-week from Monday through Friday(UTC Time), 9pm in IST and 11:30 AM in EST.

jobs:
  fetch_all_pull_requests_and_notify_using_condition_and_cron:
    runs-on: ubuntu-latest

    env:
      REPO: ${{ github.repository }}
      BRANCH: main
      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
      API_URL: https://api.github.com/repos/redhat-developer/lsp4ij/pulls
      SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
      WORKFLOW_BUILDER_WEBHOOK: ${{ secrets.WORKFLOW_BUILDER_WEBHOOK }}
      NO_PR_WORKFLOW_BUILDER_WEBHOOK: ${{ secrets.NO_PR_WORKFLOW_BUILDER_WEBHOOK }}

    steps:
      - name: Checkout repository
        uses: actions/checkout@v2

      - name: Fetch recent cache
        run: |
          gh extension install actions/gh-actions-cache

          # Fetching list of cache keys...
          # Allowed values are within the limit 1-100 ,If we give 100, only the latest 100 cache keys will be listed. Any older cache keys beyond this limit will not be included in '$cacheKeys'
          cacheKeys=$(gh actions-cache list -R $REPO -B $BRANCH -L 100 | cut -f 1 )
          
          # Extract the most recent cache key
          mostRecentCacheKey=$(echo "$cacheKeys" | head -n 1)
          
          if [ -n "$mostRecentCacheKey" ]; then
            echo "CACHE_KEY=$mostRecentCacheKey" >> $GITHUB_ENV
          else
            echo "No recent cache key found, generating a new one......"
            echo "CACHE_KEY=${{ runner.os }}-pr-cache-${{ github.run_number }}" >> $GITHUB_ENV
          fi
          
          echo "Done"

      - name: Restore cache
        id: cache-restore
        uses: actions/cache@v2
        with:
          path: cache
          key: ${{ env.CACHE_KEY }}

      - name: Ensure cache directory exists and check if cache restored
        run: |
          mkdir -p cache
          if [ -f cache/notified_prs.json ]; then
            echo "Cache restored successfully."
            cat cache/notified_prs.json
          else
            echo "Cache not restored or file does not exist.."
          fi

      - name: Fetch all opened pull request details using condition
        id: fetch_all_pull_requests_using_condition
        run: |
          # The number of results per page is limited to a maximum of 100. We need "pagination", if we require more than this limit, but for open PRs, it will be within the limit 100.
          pr_infos=$(curl -s -H "Authorization: token ${{ env.GH_TOKEN }}" \
          "${{ env.API_URL }}?state=open&direction=desc&per_page=100")
          
          echo "List of Currently Opened PRs: "
          echo "$pr_infos" | jq '.[] | {number, updated_at, draft}'

          # Load previous PR data if exists
          if [ -f cache/notified_prs.json ]; then
            previous_prs=$(cat cache/notified_prs.json)
          else
            previous_prs="[]"
          fi

          pr_list=""
          new_notified_prs="[]"
          notify=false

          for pr_info in $(echo "$pr_infos" | jq -r '.[] | @base64'); do
            _jq() {
              echo "$pr_info" | base64 --decode | jq -r "${1}"
            }

            pr_number=$(_jq '.number')
            pr_title=$(_jq '.title')
            pr_user=$(_jq '.user.login')
            pr_url=$(_jq '.html_url')
            pr_draft=$(_jq '.draft')
            pr_created_at=$(_jq '.created_at')
            pr_updated_at=$(_jq '.updated_at')

            pr_data=$(jq -n --arg number "$pr_number" --arg updated_at "$pr_updated_at" '{number: $number, updated_at: $updated_at}')
            new_notified_prs=$(echo "$new_notified_prs" | jq --argjson pr_data "$pr_data" '. += [$pr_data]')

            # Check if the PR is new or updated
            previous_pr=$(echo "$previous_prs" | jq --arg number "$pr_number" '.[] | select(.number == $number)')
            if [ -z "$previous_pr" ] || [ "$(echo "$previous_pr" | jq -r '.updated_at')" != "$pr_updated_at" ]; then
              draft_status=""
              # Checking the PR draft status to only send 'Draft: true' in the Slack message and avoid sending 'Draft: false'.
              if [ "$pr_draft" = "true" ]; then
                draft_status="\n*Draft*: true"
              fi

              pr_list="${pr_list}\n*Pull Request* #${pr_number}: ${pr_title}\n*Created by*: ${pr_user}\n*URL*: ${pr_url}${draft_status}\n*Created At*: ${pr_created_at}\n*Last Updated At*: ${pr_updated_at}\n"
              notify=true
            fi
          done
          
          echo "List of PRs that need to be sent to Slack now:"
          echo "$pr_list"

          # Save current PR data for future comparison
          echo "$new_notified_prs" > cache/notified_prs.json

          if [ "$notify" = true ]; then
            echo -e "$pr_list" > pr_list.txt
            echo "notify=true" >> $GITHUB_ENV
          else
            echo "notify=false" >> $GITHUB_ENV
          fi

      - name: Fetch closed pull requests since the last run
        id: fetch_closed_prs
        run: |
          if [ -f cache/last_run_timestamp.txt ]; then
            last_run_timestamp=$(cat cache/last_run_timestamp.txt)
          else
            last_run_timestamp=$(date -u -d "-24 hours" +%Y-%m-%dT%H:%M:%SZ)
          fi

          echo "Last run timestamp: $last_run_timestamp"
          
          
          # We used 'sort=updated' to fetch list of closed PRs with max limit of 100(Default value). In the future, we expect to have more than 100 closed PRs, so it's better to keep 'sort=updated'.
          closed_prs=$(curl -s -H "Authorization: token ${{ env.GH_TOKEN }}" \
          "${{ env.API_URL }}?state=closed&sort=updated&direction=desc&per_page=100")
          
          closed_pr_list=$(echo "$closed_prs" | jq -r \
          --arg last_run "$last_run_timestamp" \
          '.[] | select(.closed_at > $last_run) | "*Closed Pull Request* #\(.number): \(.title)\n*Closed by*: \(.user.login)\n*URL*: \(.html_url)\n*Closed At*: \(.closed_at)\n"')
          
          echo "Closed PR List since last cron job:"
          echo "$closed_pr_list"
          
          if [ -n "$closed_pr_list" ]; then
            echo -e "$closed_pr_list" > closed_pr_list.txt
            echo "notify_closed=true" >> $GITHUB_ENV
          else
            echo "notify_closed=false" >> $GITHUB_ENV
          fi      

      - name: Send Slack notification for PRs
        if: success() && (${{ env.notify }} == 'true' || ${{ env.notify_closed }} == 'true')
        run: |
          # Initialize PR lists
          pr_list=""
          closed_pr_list=""

          # Check if the open PRs file exists and read its content
          if [ -f pr_list.txt ]; then
            pr_list=$(cat pr_list.txt)
          fi

          # Check if the closed PRs file exists and read its content
          if [ -f closed_pr_list.txt ]; then
            closed_pr_list=$(cat closed_pr_list.txt)
          fi

          # Initialize payload blocks
          payload_blocks=()

          # Add open PRs section if not empty
          if [ -n "$pr_list" ]; then
            payload_blocks+=("{
              \"type\": \"header\",
              \"text\": {
                \"type\": \"plain_text\",
                \"text\": \"List of Open/New/Updated Pull Requests using Cron Job\"
              }
            }")
            payload_blocks+=("{
              \"type\": \"section\",
              \"text\": {
                \"type\": \"mrkdwn\",
                \"text\": $(echo "$pr_list" | jq -sR .)
              }
            }")
          fi

          # Add closed PRs section if not empty
          if [ -n "$closed_pr_list" ]; then
            payload_blocks+=("{
              \"type\": \"header\",
              \"text\": {
                \"type\": \"plain_text\",
                \"text\": \"List of Pull Requests Closed Since the Last Cron Job\"
              }
            }")
            payload_blocks+=("{
              \"type\": \"section\",
              \"text\": {
                \"type\": \"mrkdwn\",
                \"text\": $(echo "$closed_pr_list" | jq -sR .)
              }
            }")
          fi

          # Construct the payload
          payload=$(jq -n --argjson blocks "$(printf '%s\n' "${payload_blocks[@]}" | jq -s '.')" '
          {
            "blocks": $blocks
          }')

          # Send the payload to Slack
          curl -X POST -H 'Content-type: application/json' --data "$payload" $SLACK_WEBHOOK_URL || echo "Slack notification failed with status code: $?"

      - name: Save current timestamp
        run: |
          current_timestamp=$(date -u +%Y-%m-%dT%H:%M:%SZ)
          echo "$current_timestamp" > cache/last_run_timestamp.txt
          echo "Current run timestamp saved: $current_timestamp"

      - name: Verify Cache Save
        if: always()
        run: |
          echo "Checking saved cache content...."
          ls -l cache/
          cat cache/notified_prs.json

      - name: Save cache
        if: always()
        uses: actions/cache@v2
        with:
          path: cache
          key: ${{ runner.os }}-pr-cache-${{ github.run_number }}

      - name: Cleanup the restored cache key
        run: |

          # Fetching list of cache keys........
          # Allowed values are within the limit 1-100
          cacheKeys=$(gh actions-cache list -R $REPO -B $BRANCH -L 100 | cut -f 1 )
          echo "Cache keys-->: $cacheKeys"

          # Extract the most recent cache key
          mostRecentCacheKey=$(echo "$cacheKeys" | head -n 1)
          
          # Setting this to not fail the workflow while deleting cache key
          set +e
          if [ -n "$mostRecentCacheKey" ] && [[ $mostRecentCacheKey == Linux-pr-cache-* ]]; then
            echo "Deleting the most recent cache key..."
            gh actions-cache delete $mostRecentCacheKey -R $REPO -B $BRANCH --confirm
          else
            echo "No cache keys found."
          fi

          echo "Done"

      - name: Slack Notification for Response message
        if: success()
        run: |
          payload=$(jq -n '
          {
            "blocks": [
              {
                "type": "header",
                "text": {
                  "type": "plain_text",
                  "text": "Slack Notification to perform Workflow Builder Action"
                }
              }
            ]
          }')

          if [[ "${{ env.notify }}" == "false" && "${{ env.notify_closed }}" == "false" ]]; then
            webhook_url=$NO_PR_WORKFLOW_BUILDER_WEBHOOK
          else
            webhook_url=$WORKFLOW_BUILDER_WEBHOOK
          fi

          if [ -n "$webhook_url" ]; then
            curl -X POST -H 'Content-type: application/json' --data "$payload" "$webhook_url" || echo "Slack notification failed with status code: $?"
          else
            echo "Webhook URL not found. Slack notification not sent."
          fi

    # 'secrets.GITHUB_TOKEN' is automatically provided by GitHub Actions for each workflow run. We don't need to manually create or manage this token.
    # Below, the workflow is granting "write" access to the actions scope of the GITHUB_TOKEN. This enables the workflow to be able to delete cache keys.
    # If the "write" permission does not enable the ability to delete the cache keys, then the repository owner will need to create a Personal Access Token (PAT) with write permissions, add it as a secret, and then specify the name in GH_TOKEN.
    permissions:
      actions: write