extract github followers

.gitignore

outputs/*
config.js

config.js

// if goes to public git repository
// this file must be ignored by .gitignore
module.exports = {
  github_token: "xxx"
};

extract-github-followers.js

const Promise = require("bluebird");
const fetch = require("node-fetch");
const mkdirp = require("mkdirp");
const fs = require("fs");
const path = require("path");
const keys = require("./config");

// file utils

const saveTo = (
  filePath,
  data,
  parse = data => JSON.stringify(data, null, 2)
) => {
  const to = path.resolve(`${path.dirname(require.main.filename)}/${filePath}`);

  mkdirp(path.dirname(to));
  return new Promise((resolve, reject) => {
    fs.writeFile(to, parse(data), "utf8", () => resolve(to));
  });
};

// graphql utils

const repoFollowersQuery = `
  query RepoFollowers($first: Int!, $after: String, $repoOwner: String!, $repoName: String!)  {
    repository(owner: $repoOwner, name: $repoName) {
      stargazers(first: $first, after: $after) {
        edges {
          cursor
          node {
            login
            name
            followers {
              totalCount
            }
          }
        }
      }
    }
  }
`;

const fetchQuery = (query, variables = {}) =>
  fetch("https://api.github.com/graphql", {
    body: JSON.stringify({ query, variables }),
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      Accept: "application/json",
      Authorization: `bearer ${keys.github_token}`
    }
  }).then(r => r.json());

const fetchAllByCursor = (query, variables, getAfterCursorFromData) => {
  const responses = [];

  const recursiveFetchQuery = (query, variables) =>
    fetchQuery(query, variables).then(res => {
      const { data, errors } = res;
      responses.push(res);

      if (errors) {
        return Promise.resolve(responses);
      } else {
        const after = getAfterCursorFromData(data);
        if (!after) {
          return Promise.resolve(responses);
        }

        const nextVariables = { ...variables, after };
        return recursiveFetchQuery(query, nextVariables);
      }
    });

  return recursiveFetchQuery(query, variables);
};

/* extract data logic */

const getEdgeData = ({ node: { name, login, followers } }) => ({
  name,
  login,
  followers: followers.totalCount
});

const getFollowersStargazersData = repo => {
  const [repoOwner, repoName] = repo.split("/");
  const first = 100;
  let looptime = 1;

  fetchAllByCursor(repoFollowersQuery, { first, repoOwner, repoName }, data => {
    console.log(
      `Fetching more ${first}. Total fetched range: ${looptime * first}`
    );
    const edges = data.repository.stargazers.edges;
    if (!edges.length) return false;
    looptime++;
    return edges[edges.length - 1].cursor;
  })
    // pick data
    .then(responses =>
      responses.reduce(
        (acc, res) => [
          ...acc,
          ...res.data.repository.stargazers.edges.map(getEdgeData)
        ],
        []
      )
    )
    // sort data by followers
    .then(data => [...data].sort((a, b) => b.followers - a.followers))
    // save data to json
    .then(data => {
      saveTo(`./outputs/${repoOwner}.${repoName}.json`, data).then(fullPath =>
        console.log(`Done! Saved to ${fullPath}`)
      );
    });
};

getFollowersStargazersData(process.argv[2]);