ChromeHeadless 79.0.3945 disconnected on jenkins

Hi, I have a problem with executing unit tests on jenkins.

Dependencies:

"@angular-devkit/build-angular": "^0.803.23",
"jasmine-core": "~3.5.0",
"jasmine-spec-reporter": "~4.2.1",
"karma": "^4.4.1",
"karma-chrome-launcher": "^3.1.0",
"karma-coverage-istanbul-reporter": "~2.1.1",
"karma-jasmine": "~3.1.0",
"karma-jasmine-html-reporter": "^1.5.1",
"puppeteer": "^2.0.0",

My karma’s configuration is:

const process = require('process');
process.env.CHROME_BIN = require('puppeteer').executablePath();

module.exports = function (config) {
  config.set({
    basePath: '',
    browserNoActivityTimeout: 50000,
    frameworks: ['jasmine', '@angular-devkit/build-angular'],
    plugins: [
      require('karma-jasmine'),
      require('karma-chrome-launcher'),
      require('karma-jasmine-html-reporter'),
      require('karma-coverage-istanbul-reporter'),
      require('@angular-devkit/build-angular/plugins/karma')
    ],
    client:{
      clearContext: false // leave Jasmine Spec Runner output visible in browser
    },
    coverageIstanbulReporter: {
      reports: [ 'html', 'lcovonly' ],
      fixWebpackSourcePaths: true
    },
    angularCli: {
      environment: 'dev'
    },
    reporters: ['progress', 'kjhtml'],
    port: 8080,
    colors: true,
    logLevel: config.LOG_INFO,
    autoWatch: true,
    browsers: ['ChromeHeadless'],
    singleRun: true,
    customLaunchers: {
      ChromeHeadless: {
        base: 'Chrome',
        flags: [
          '--headless',
          '--disable-gpu',
          '--remote-debugging-port=9222',
          '--no-sandbox',
          '--disable-dev-shm-usage'
        ]
      }
    }
  });
};

Error messages:

20 01 2020 13:54:20.183:INFO [karma-server]: Karma v4.4.1 server started at http://0.0.0.0:8080/
13:54:21 20 01 2020 13:54:20.191:INFO [launcher]: Launching browsers ChromeHeadless with concurrency unlimited
13:54:21 20 01 2020 13:54:20.198:INFO [launcher]: Starting browser Chrome
13:54:59 20 01 2020 13:54:58.982:INFO [HeadlessChrome 79.0.3945 (Linux 0.0.0)]: Connected on socket XnNj1UhzUvpfZH5iAAAA with id 88283591
13:55:32 20 01 2020 13:55:31.108:WARN [HeadlessChrome 79.0.3945 (Linux 0.0.0)]: Disconnected (0 times)reconnect failed before timeout of 2000ms (ping timeout)
13:55:32 HeadlessChrome 79.0.3945 (Linux 0.0.0) ERROR
13:55:32   Disconnectedreconnect failed before timeout of 2000ms (ping timeout)
13:55:32 
13:55:32 HeadlessChrome 79.0.3945 (Linux 0.0.0) ERROR
13:55:32   Disconnectedreconnect failed before timeout of 2000ms (ping timeout)

[breautek]

For me, I’ve discovered the disconnect issue was actually due to flawed logic in my code base, where there was a memory leak of event listeners.

After karma disconnected from chrome, we noticed chrome was still going full throttle eating up 100% of the CPU, which led us to start commenting out unit tests until the problem went away. Eventually this led us to isolate the problem to one group of unit tests and eventually to a specific class in our code base.

Hope this helps some one.

[breautek]

It’s not limited to jenkins, seeing this error, just on my dev machine running Ubuntu 18, and my college using Mac OS X Catalina.

It happens very frequently, but sometimes all tests will run without disconnects for me. We’ve been run tests very often, so I’m fairly confident the issue only appears as of Chrome 79.0.3945

"karma": "4.4.1",
"karma-chrome-launcher": "3.1.0",

We started converting sourcemaps from inline to URL refs about six months ago because of browser failures on large test code.

My tests is running with inline sourcemaps, will change them over and report back results…

EDIT Changing my devtool config from inline-source-map to source-map or none doesn’t appear to solve the problem for me.