Failed: EPIPE write EPIPE frequently seen when SELENIUM_PROMISE_MANAGER: false

Bug report

• Node Version: 6.9.1
• Protractor Version: 5.1.2
• Angular Version: 4.0.0
• Browser(s): Chrome Version 57.0.2987.133 (64-bit)
• Operating System and Version OS X Version 10.10.5 (14F2315)
• Your protractor configuration file

// Protractor configuration file, see link for more information
// https://github.com/angular/protractor/blob/master/docs/referenceConf.js

/* Third-party */
let HtmlScreenshotReporter = require('protractor-jasmine2-screenshot-reporter');
let JUnitXmlReporter = require('jasmine-reporters').JUnitXmlReporter;
let SpecReporter = require('jasmine-spec-reporter').SpecReporter;

/* Custom */
let setup = require('./e2e/setup/setup');

exports.config = {
  allScriptsTimeout: 11000,
  specs: [
    './e2e/**/*.e2e-spec.ts'
  ],
  capabilities: {
    'browserName': 'chrome'
  },
  directConnect: true,
  baseUrl: 'http://localhost:4200/',
  SELENIUM_PROMISE_MANAGER: false,
  framework: 'jasmine',
  jasmineNodeOpts: {
    showColors: true,
    defaultTimeoutInterval: 30000,
    print: function() {}
  },
  useAllAngular2AppRoots: true,
  beforeLaunch: function() {
    require('ts-node').register({
      project: 'e2e'
    });
  },
  onPrepare: function() {
    jasmine.getEnv().addReporter(new SpecReporter());
    jasmine.getEnv().addReporter(new JUnitXmlReporter({
      consolidateAll: true,
      savePath: browser.params.output || 'protractor/log',
      filePrefix: 'protractor_output'
    }));
    jasmine.getEnv().addReporter(new HtmlScreenshotReporter({
      cleanDestination: true,
      dest: 'protractor/log',
      filename: 'index.html'
    }));
    setup();
  }
};

• A relevant example test

import { browser } from 'protractor';

import { A2Page } from './app.po';
import { NavPartial } from './nav/nav.po';
import { SettingsPage } from './settings/settings.po';
import { Utils } from './utils';

let utils = new Utils();

describe('a2 root', function() {
  let page: A2Page = new A2Page();
  let navPartial: NavPartial = new NavPartial();
  let settingsPage: SettingsPage = new SettingsPage();

  it('should be able to navigate to', () => {
    return page.navigateTo();
  });

  it('should take user to Settings', () => {
    return settingsPage.getTitle().then(title => {
      return expect(title).toEqual('Title');
    }).then(() => {
      return settingsPage.getSubtitle();
    }).then(subtitle => {
      return expect(subtitle).toEqual('Subtitle');
    });
  });

  it('should have a Home menu', () => {
    return page.navigateTo().then(() => {
      return navPartial.isHomePresent();
    }).then(present => {
      return expect(present).toBeTruthy();
    });
  });

  it('should have an Info menu', () => {
    return page.navigateTo().then(() => {
      return navPartial.isInfoPresent();
    }).then(present => {
      return expect(present).toBeTruthy();
    });
  });
});

• Output from running the test

$ npm run e2e -- --params.baseUrl 'https://myurl'

> a2@0.0.0 pree2e /Users/me/a2
> webdriver-manager update

[13:56:14] I/update - chromedriver: file exists /Users/me/a2/node_modules/protractor/node_modules/webdriver-manager/selenium/chromedriver_2.29.zip
[13:56:14] I/update - chromedriver: unzipping chromedriver_2.29.zip
[13:56:14] I/update - chromedriver: setting permissions to 0755 for /Users/me/a2/node_modules/protractor/node_modules/webdriver-manager/selenium/chromedriver_2.29
[13:56:14] I/update - chromedriver: chromedriver_2.29 up to date
[13:56:14] I/update - selenium standalone: file exists /Users/me/a2/node_modules/protractor/node_modules/webdriver-manager/selenium/selenium-server-standalone-3.4.0.jar
[13:56:14] I/update - selenium standalone: selenium-server-standalone-3.4.0.jar up to date
[13:56:14] I/update - geckodriver: file exists /Users/me/a2/node_modules/protractor/node_modules/webdriver-manager/selenium/geckodriver-v0.16.1.tar.gz
[13:56:14] I/update - geckodriver: unzipping geckodriver-v0.16.1.tar.gz
[13:56:14] I/update - geckodriver: setting permissions to 0755 for /Users/me/a2/node_modules/protractor/node_modules/webdriver-manager/selenium/geckodriver-v0.16.1
[13:56:14] I/update - geckodriver: geckodriver-v0.16.1 up to date

> a2@0.0.0 e2e /Users/me/a2
> $(npm bin)/protractor "--params.baseUrl" "https://myurl"

[13:56:16] I/launcher - Running 1 instances of WebDriver
[13:56:16] I/direct - Using ChromeDriver directly...
Spec started

  a2 root
    ✓ should be able to navigate to
    ✓ should take user to Settings
    ✓ should have a Home menu
    ✗ should have an Info menu
      - Failed: EPIPE write EPIPE

**************************************************
*                    Failures                    *
**************************************************

1) a2 root should have an Info menu
  - Failed: EPIPE write EPIPE

Executed 4 of 4 specs (1 FAILED) in 22 secs.
[13:56:41] I/launcher - 0 instance(s) of WebDriver still running
[13:56:41] I/launcher - chrome #01 failed 1 test(s)
[13:56:41] I/launcher - overall: 1 failed spec(s)
[13:56:41] E/launcher - Process exited with error code 1

npm ERR! Darwin 14.5.0
npm ERR! argv "/Users/me/.nvm/versions/node/v6.9.1/bin/node" "/Users/me/.nvm/versions/node/v6.9.1/bin/npm" "run" "e2e" "--" "--params.baseUrl" "https://myurl"
npm ERR! node v6.9.1
npm ERR! npm  v3.10.8
npm ERR! code ELIFECYCLE
npm ERR! a2@0.0.0 e2e: `$(npm bin)/protractor "--params.baseUrl" "https://myurl"`
npm ERR! Exit status 1
npm ERR! 
npm ERR! Failed at the a2@0.0.0 e2e script '$(npm bin)/protractor "--params.baseUrl" "https://myurl"'.
npm ERR! Make sure you have the latest version of node.js and npm installed.
npm ERR! If you do, this is most likely a problem with the a2 package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR!     $(npm bin)/protractor "--params.baseUrl" "https://myurl"
npm ERR! You can get information on how to open an issue for this project with:
npm ERR!     npm bugs a2
npm ERR! Or if that isn't available, you can get their info via:
npm ERR!     npm owner ls a2
npm ERR! There is likely additional logging output above.

npm ERR! Please include the following file with any support request:
npm ERR!     /Users/me/a2/npm-debug.log

Also excerpt from npm-debug.log:

18 verbose stack Exit status 1
18 verbose stack     at EventEmitter.<anonymous> (/Users/me/.nvm/versions/node/v6.9.1/lib/node_modules/npm/lib/utils/lifecycle.js:255:16)
18 verbose stack     at emitTwo (events.js:106:13)
18 verbose stack     at EventEmitter.emit (events.js:191:7)
18 verbose stack     at ChildProcess.<anonymous> (/Users/me/.nvm/versions/node/v6.9.1/lib/node_modules/npm/lib/utils/spawn.js:40:14)
18 verbose stack     at emitTwo (events.js:106:13)
18 verbose stack     at ChildProcess.emit (events.js:191:7)
18 verbose stack     at maybeClose (internal/child_process.js:877:16)
18 verbose stack     at Process.ChildProcess._handle.onexit (internal/child_process.js:226:5)

• Steps to reproduce the bug

1. Use approximately the Node and Angular versions mentioned, Chrome browser, possibly Mac OS X. (Not yet certain how specific issue is to that combination.)
2. Set SELENIUM_PROMISE_MANAGER: false in config (disable control flow).
3. Due to (2) above, use promises everywhere in your test suite.
4. Have a suite that for each of several tests, gets a URL and clicks or checks element presence.
5. Very quickly you will start hitting Failed: EPIPE write EPIPE errors unpredictably.

I’m not using await. I cannot identify any unhandled promises in the test code either (and I’m experienced with promises), although that has been suggested in some of the comments, so I have to allow for that possibility. Still, it’s surprising that node would crash on an unhandled promise, if that’s the case. So it seems there’s a node bug in here somewhere, in addition to whatever problem there may be in my test or protractor or webdriver, etc.

• The URL you are running your tests against (if relevant)

Sorry, it’s not public.

[devoto13]

In our project EPIPE errors were appearing, because tests (in TypeScript) were incorrectly using awaits. And therefore unhandled Promise rejections were happening randomly and leading to these errors. Once I’ve fixed incorrect usages we don’t have these errors anymore on Node 8.

Try to check your tests carefully for incorrect usages of await (either missing or redundant) or just incorrect Promise chaining (for example when you forgot to return Promise from helper methods). In our case typical error was using:

browser.wait(await EC.invisibilityOf(fade)); // incorrect

instead of:

await browser.wait(EC.invisibilityOf(fade)); // correct

Maybe it will help somebody, who also has this issue.

[Xaz16]

@renehamburger thank you. After add this one to onPrepare section of my protractor.conf.js:

let currentCommand = Promise.resolve();
// Serialise all webdriver commands to prevent EPIPE errors
const webdriverSchedule = browser.driver.schedule;
browser.driver.schedule = (command, description) => {
   currentCommand = currentCommand.then(() =>
      webdriverSchedule.call(browser.driver, command, description)
    );
    return currentCommand;
};

Error ‘Failed: EPIPE write EPIPE’ is gone.