Node.jsでGitHubAPIv4を叩くサンプル(ページネーションあり) / call GitHub API v4 with pagination.

GitHubAPIv4-pagination-sample.js

//
// Node.jsでGitHubAPIv4を叩くサンプル(ページネーションあり)
//

const https = require('https');

const options = {
    method: 'POST',
    headers: {
        'Authorization': 'bearer ' + process.env.GITHUB_TOKEN,
        'Content-type': 'application/json',
        'user-agent': 'node.js'
    }
};

// GitHubAPIv4のクエリを生成する
const buildQuery = (endCursor) => {
    // 文字列の場合はダブルクォーテーションで囲む必要がある
    if (endCursor != null) endCursor = '"' + endCursor + '"';

    const query = `
        query{
          repository(name: "ec-cube", owner: "EC-CUBE") {
            pullRequests(first: 10, after: ${endCursor}, orderBy: {field: CREATED_AT, direction: ASC}, states: OPEN) {
              pageInfo {
                hasNextPage
                endCursor
              }
              edges {
                node {
                  number
                  title
                  url
                }
                cursor
              }
            }
          }
        }`;

    return query;
};

// APIからデータを取得する
const fetchPullRequests = (endCursor, output) => {
    return new Promise((resolve) => {
        const req = https.request('https://api.github.com/graphql', options, (res) => {
            const data = [];
            res.on('data', (d) => {
                data.push(d);
            });
            res.on('end', () => {
                const buf = Buffer.concat(data);
                output(buf);

                const jsonObject = JSON.parse(buf);
                let hasNextPage = jsonObject.data.repository.pullRequests.pageInfo.hasNextPage;
                let endCursor = hasNextPage ? jsonObject.data.repository.pullRequests.pageInfo.endCursor : null;

                resolve(endCursor);
            });
        }).on('error', (e) => {
            console.error(e);
        });

        const query = buildQuery(endCursor);
        req.write(JSON.stringify({query}));
        req.end();
    }).then((endCursor) => {
        if (endCursor == null) return;
        return fetchPullRequests(endCursor, output);
    });
};

// 出力処理
const output = (data) => {
    console.log('%s', data);
};

fetchPullRequests(null, output).then();