GitHub monthly issues stats

index.ts

import fs from 'node:fs';
import { asyncForEach, asyncForEachStrict } from '@wojtekmaj/async-array-utils';
import chalk from 'chalk';
import { endOfMonth, formatISO, startOfMonth } from 'date-fns';

const CACHE_DIR = '.cache';
const GITHUB_API_URL = 'https://api.github.com';
const GITHUB_TOKEN = process.env.GITHUB_TOKEN;
const DEBUG = process.env.DEBUG === 'true';

if (!GITHUB_TOKEN) {
  throw new Error('GITHUB_TOKEN environment variable must be set');
}

function log(...args: unknown[]) {
  if (DEBUG) {
    console.log(...args);
  }
}

type SearchResultsPage = {
  total_count: number;
};

class NetworkError extends Error {
  status: number;

  constructor(status: number, statusText: string) {
    super(statusText);
    this.name = 'NetworkError';
    this.status = status;
  }
}

/**
 * Fetches a URL and caches it in the .cache directory. On subsequent calls, it
 * will return the cached version if it exists.
 */
async function fetchWithCache(input: string | URL, init?: RequestInit): Promise<string> {
  // log(chalk.gray`Getting %s…`, input);

  const cacheKey = input
    .toString()
    .replace(/[^a-z0-9]/gi, '_')
    .toLowerCase();
  const cachePath = `${CACHE_DIR}/fetch/${cacheKey}`;
  const cacheExists = fs.existsSync(cachePath);

  // If the cache exists, return it
  if (cacheExists) {
    // log(chalk.gray`  Retrieving from cache`);
    const cachedFile = fs.readFileSync(cachePath, 'utf-8');

    return cachedFile;
  }

  // Otherwise, fetch the URL
  // log(chalk.gray`  Fetching from network`, input);
  const response = await fetch(input, init);

  if (!response.ok) {
    throw new NetworkError(response.status, response.statusText);
  }

  const requestText = await response.text();

  // Ensure the cache directory exists
  fs.mkdirSync(CACHE_DIR, { recursive: true });

  // Write the response to the cache
  fs.writeFileSync(cachePath, requestText);

  return requestText;
}

const startDate = new Date(2020, 0, 1);
const endDate = new Date();

// List of monthly date ranges
const ranges: [Date, Date][] = [];

// Generate the list of monthly date ranges
for (let date = startDate; date <= endDate; date.setMonth(date.getMonth() + 1)) {
  const start = startOfMonth(date);
  const end = endOfMonth(date);
  ranges.push([start, end]);
}

const results: number[] = [];

await (DEBUG ? asyncForEachStrict : asyncForEach)(ranges, async ([date1, date2], i) => {
  const date1String = formatISO(date1, { representation: 'date' });
  const date2String = formatISO(date2, { representation: 'date' });

  log(chalk.gray`Fetching issues from %s to %s`, date1String, date2String);

  const url = new URL(`${GITHUB_API_URL}/search/issues`);
  url.searchParams.set(
    'q',
    `"this makes the require call ambiguous and unsound" created:${date1String}..${date2String}`,
  );

  const rawResponse = await fetchWithCache(url, {
    headers: {
      Authorization: `token ${process.env.GITHUB_TOKEN}`,
    },
  });

  const response = JSON.parse(rawResponse) as SearchResultsPage;

  results[i] = response.total_count;
});

log(results);