github-pull-reminder-webtask-hack.js

'use strict';

const {promisify} = require('util');
const request = promisify(require('request'));
const Promise = global.Promise;

const getPullRequestsQuery = (owner, name) => {
  return `
    query GET_REVIEWS_QUERY {
      repository(owner:"${owner}", name:"${name}") {
        pullRequests(first:10,states:OPEN) {
          edges {
            node {
              id
              title
              createdAt
              reviewRequests(first:10) {
                edges {
                  node {
                    id
                    requestedReviewer {
                      ... on User {
                        login
                      }
                    }
                  }
                }
              }
              reviews(first:10) {
                edges {
                  node {
                    id
                    author {
                      ... on User {
                        login
                      }
                    }
                  }
                }
              }
            }
          }
        }
      }
    }
  `;
};

const createCommentMutation = (pullRequestId, comment) => {
  return `
    mutation {
      addComment(input:{subjectId:"${pullRequestId}", body:"${comment}"}) {
        clientMutationId
      }
    }
  `;
}

const sendGitHubQuery = async (token, query) => {
    const response = await request({
      method: 'post',
      url: 'https://api.github.com/graphql',
      json: {query},
      headers: {
        Authorization: `Bearer ${token}`,
        ['User-Agent']: "PR nudger",
        ['Content-Type']: 'application/json'
      }
    });

    return response.body && response.body.data;
}

module.exports = async function (context) {
  const GITHUB_TOKEN = context.secrets.GITHUB_TOKEN;
  const OWNER = context.secrets.OWNER;
  const REPO = context.secrets.REPO;
  
  const data = await sendGitHubQuery(GITHUB_TOKEN, getPullRequestsQuery(OWNER, REPO));

  const sendReviewReminderIfNeeded = async (pullRequest) => {
    const reviewRequests = pullRequest.reviewRequests.edges.map(edge => edge.node);
    

    if (reviewRequests.length > 0) {
      const comment = `hey ${reviewRequests.map(reviewRequest => `@${reviewRequest.requestedReviewer.login}`).join(' ')}
        this pull request awaiting your review
      `;

      await sendGitHubQuery(GITHUB_TOKEN, createCommentMutation(pullRequest.id, comment));
    }
  }
  
  if (data.repository && data.repository.pullRequests) {
    const pullRequests = data.repository.pullRequests.edges.map(edge => edge.node);

    await Promise.all(pullRequests.map(sendReviewReminderIfNeeded));
  }

  return 'OK';
};

GitHub pull reminder hook build on http://webtask.io.

Set secrets to

GITHUB_TOKEN=<your personal github access token>
OWNER=<repo owner>
REPO=<repo name>

Setup schedule to whenever you want it to be executed, e.g. every 3 hours, every hour and etc.