changelog.js

const { spawn } = require("child_process");

var packageJson = require("./package.json");
var fs = require("fs");
const workspace = process.env.GITHUB_WORKSPACE;
const date = new Date();

const file = "./CHANGELOG.md";

fs.readFile(file, "utf8", function (err, data) {
  if (err) {
    return console.log(err);
  }

  const [latestPr] = data
    .split("/pull/")
    .map((el) => parseInt(el.split(")\n")[0]))
    .filter((el) => el)
    .sort()
    .reverse();

  const replacement = `## [Unreleased]
## [[${
    packageJson.version
  }](https://github.com/tokamak-network/titan-sdk-dapp/pull/${
    latestPr + 1
  })] - ${date.toISOString().split("T")[0]}
  `;

  var result = data.replace("## [Unreleased]", replacement);

  fs.writeFileSync(file, result, "utf8", function (err) {
    if (err) {
      return console.log(err);
    }
  });
  pushChanges();
});

const pushChanges = async () => {
  await runInWorkspace("git", [
    "config",
    "user.name",
    `"${process.env.GITHUB_USER || "Automated Changelog"}"`,
  ]);
  await runInWorkspace("git", [
    "config",
    "user.email",
    `"${
      process.env.GITHUB_EMAIL ||
      "gh-action-changelog-edit@users.noreply.github.com"
    }"`,
  ]);

  const remoteRepo = `https://${process.env.GITHUB_ACTOR}:${process.env.GITHUB_TOKEN}@github.com/${process.env.GITHUB_REPOSITORY}.git`;
  await runInWorkspace("git", ["commit", "-a", "-m", "update changelog"]);
  await runInWorkspace("git", ["push", remoteRepo, "--follow-tags"]);
  await runInWorkspace("git", ["push", remoteRepo, "--tags"]);
};

function runInWorkspace(command, args) {
  return new Promise((resolve, reject) => {
    console.log("runInWorkspace | command:", command, "args:", args);
    const child = spawn(command, args, { cwd: workspace });
    let isDone = false;
    const errorMessages = [];
    child.on("error", (error) => {
      if (!isDone) {
        isDone = true;
        reject(error);
      }
    });
    child.stderr.on("data", (chunk) => errorMessages.push(chunk));
    child.on("exit", (code) => {
      if (!isDone) {
        if (code === 0) {
          resolve();
        } else {
          reject(
            `${errorMessages.join("")}${EOL}${command} exited with code ${code}`
          );
        }
      }
    });
  });
}