Advanced GitHub Action Script for Stale Pull Request Management

workflow.yml

name: Mark stale pull requests in Shepherd repo

on:
  schedule:
  - cron: '0 0 * * 1'  # Runs every Monday at midnight

jobs:
  stale:
    runs-on: ubuntu-latest
    timeout-minutes: 5

    steps:      
      - name: Checkout code
        uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5
        
      - name: Check PRs and compile report
        id: compile_report
        uses: actions/github-script@211cb3fefb35a799baa5156f9321bb774fe56294
        with:
          script: |
            const FIVE_DAYS_AGO = new Date(new Date().setDate(new Date().getDate() - 5)); 
            const THREE_DAYS_AGO = new Date(new Date().setDate(new Date().getDate() - 3));
            const STATES_COMPARE = ["COMMENTED", "CHANGES_REQUESTED"];

            // Function to fetch pull requests
            async function fetchPullRequests() {
                return await github.paginate(github.rest.pulls.list, {
                    owner: 'rancher',
                    repo: 'shepherd',
                    state: 'open',
                    per_page: 100,
                });
            }

            // Function to fetch reviews for a pull request
            async function fetchReviews(owner, repo, pull_number) {
                return await github.rest.pulls.listReviews({
                    owner,
                    repo,
                    pull_number,
                    per_page: 100,
                });
            }

            // Process pull requests and compile report
            async function processPullRequests(prs) {
                let report = {
                    noReviewsReport: '',
                    needsReviews: '',
                    needsChanges: '',
                    needsMerge: '',
                    hasErrors: ''
                };
                
                for (const pr of prs) {
                    const createdDate = new Date(pr.created_at);
                    let lastReviewDate = null;
                    let lastReviewStateOne = "";
                    let lastReviewStateTwo = "";
                    let numberOfApprovedState = 0;

                    try {
                        const reviews = await fetchReviews('rancher', 'shepherd', pr.number);
                        if (reviews.data.length == 0 && createdDate < FIVE_DAYS_AGO) {
                            report.noReviewsReport += `${pr.title} #${pr.number} ${pr.html_url} ${pr.user.login}\n`;
                        } else {
                            processReviews(reviews.data, &lastReviewDate, &lastReviewStateOne, &lastReviewStateTwo, &numberOfApprovedState);
                        }
                    } catch (error) {
                        report.hasErrors += `${pr.title} (#${pr.number}) ${pr.html_url} - Error: ${error} \n`;
                    }

                    classifyPR(pr, lastReviewDate, lastReviewStateOne, lastReviewStateTwo, numberOfApprovedState, report);
                }

                return compileFullReport(report);
            }

            // Process reviews to determine the latest review states
            function processReviews(reviews, lastReviewDate, lastReviewStateOne, lastReviewStateTwo, numberOfApprovedState) {
                for (const review of reviews) {
                    const reviewDate = new Date(review.submitted_at);
                    if (!lastReviewDate || reviewDate > lastReviewDate) {
                        lastReviewDate = reviewDate;
                        lastReviewStateTwo = lastReviewStateOne;
                        lastReviewStateOne = review.state;
                        if (review.state === "APPROVED") {
                            numberOfApprovedState++;
                        }
                    }
                }
            }

            // Classify pull requests based on review states and times
            function classifyPR(pr, lastReviewDate, lastReviewStateOne, lastReviewStateTwo, numberOfApprovedState, report) {
                const updatedDate = new Date(pr.updated_at);
                if (lastReviewDate) {
                    if (lastReviewDate < THREE_DAYS_AGO && updatedDate <= lastReviewDate && STATES_COMPARE.includes(lastReviewStateOne) && STATES_COMPARE.includes(lastReviewStateTwo)) {
                        report.needsChanges += `${pr.title} (#${pr.number}) ${pr.html_url} ${pr.user.login} \n`;
                    } else if (updatedDate > lastReviewDate && updatedDate < THREE_DAYS_AGO) {
                        report.needsReviews += `${pr.title} (#${pr.number}) ${pr.html_url} ${pr.user.login} \n`;
                    } else if (numberOfApprovedState >= 2 && !STATES_COMPARE.includes(lastReviewStateOne)) {
                        report.needsMerge += `${pr.title} (#${pr.number}) ${pr.html_url} ${pr.user.login} \n`;
                    }
                }
            }

            // Compile the full report from segments
            function compileFullReport(report) {
                let fullReport = '';
                if (report.noReviewsReport) {
                    fullReport += `PRs with no reviews yet: \n` + report.noReviewsReport +`\n\n`;
                }
                if (report.needsReviews) {
                    fullReport += `PRs that need reviews: \n` + report.needsReviews +`\n\n`;
                }
                if (report.needsChanges) {
                    fullReport += `PRs with changes requested: \n` + report.needsChanges +`\n\n`;
                }
                if (report.needsMerge) {
                    fullReport += `PRs that need to be merged: \n` + report.needsMerge;
                }
                if (report.hasErrors) {
                    fullReport += `PRs that have errors when fetching: \n` + report.hasErrors;
                }
                return fullReport;
            }

            const prs = await fetchPullRequests();
            return processPullRequests(prs);

          result-encoding: string

      - name: Notify on Slack
        run: |
          result="${{ steps.compile_report.outputs.result }}"
          if [[ -n "$result" ]]; then 
            curl -X POST -H 'Content-type: application/json' --data "{\"text\":\"PR Status Report:\n$result\"}" ${{ secrets.SLACK_WEBHOOK_URL }}
          else
            curl -X POST -H 'Content-type: application/json' --data '{"text":"PR Status Report: There are errors please check the GH actions logs"}' ${{ secrets.SLACK_WEBHOOK_URL }}
          fi
        shell: bash