runCypressCi.ts

import { ChildProcess, spawn } from 'child_process';
import * as execa from 'execa';
const nodeCleanup = require('node-cleanup');
const terminate = require('terminate');
process.env.NODE_ENV = 'e2e';

let childProcesses: ChildProcess[] = [];

function start(cmd: string) {
  const proc = execa.shell(cmd);
  childProcesses.push(proc);
  proc.stdout.pipe(process.stdout);
  proc.stderr.pipe(process.stderr);
  return proc;
}

function emitsToken(proc: ChildProcess, token: string) {
  return new Promise<ChildProcess>((resolve, reject) => {
    proc.stdout.on('data', data => {
      if (data.toString().includes(token)) {
        resolve();
      }
    });
    proc.stderr.on('error', err => reject(err));
  });
}

function terminatePromise(proc: ChildProcess) {
  return new Promise((resolve, reject) => {
    terminate(proc.pid, err => {
      if (err) {
        reject(err);
      } else {
        resolve();
      }
    });

  });
}

let cypressStarted = false;
Promise.all([
  emitsToken(start('some server'), 'some token'),
  emitsToken(start('some server'), 'some token '),
  emitsToken(start('ng serve --prod --environment=e2e'), 'webpack: Compiled successfully'),
])
.then(processes => {
  console.log('processes stable, starting Cypress');
  cypressStarted = true;
  const cypress = start('yarn e2e');
  cypress.once('exit', exitCode => {
    console.log('Cypress done');
    Promise.all(childProcesses.map(p => terminatePromise(p)))
      .then(() => {
        process.exit(exitCode);
      })
      .catch(err => {
        console.log(err);
        process.exit(exitCode);
      });
  });
})
.catch(err => process.exit(1));

// if we're not built before 5 minutes
setTimeout(() => {
  if (!cypressStarted) {
    process.exit(1);
  }
}, 1000 * 60 * 5); // 10 minutes

nodeCleanup((exitCode, signal) => {
  console.log('');
  console.log('CLEANING UP');
  if (signal) {
    Promise.all(childProcesses.map(p => terminatePromise(p)))
      .then(() => {
        process.kill(process.pid, signal);
      })
      .catch(err => {
        console.log(err);
        process.kill(process.pid, signal);
      });

    nodeCleanup.uninstall(); // don't call cleanup handler again
    return false;
  }
});