Test runner node cannot see selenium-hub. Getting Error: ECONNREFUSED connect ECONNREFUSED 127.0.0.1:4444

Question

In a nutshell, there is additional container as a test runner which cannot reach the selenium-hub. So, tests are failed.

This container was added for running test on cloud by using cloud build.

I created docker-compose as below:

 version: "3"
    services:
      selenium-hub:
        image: selenium/hub:4.0.0-rc-1-prerelease-20210804
        container_name: selenium-hub
        ports:
          - "4444:4444"
        expose: 
          - 4444
    
      chrome:
        image: selenium/node-chrome:4.0.0-rc-1-prerelease-20210804
        shm_size: 2gb
        depends_on:
          - selenium-hub
        environment:
          - SE_EVENT_BUS_HOST=selenium-hub
          - SE_EVENT_BUS_PUBLISH_PORT=4442
          - SE_EVENT_BUS_SUBSCRIBE_PORT=4443
        ports:
          - "6900:5900"
    
      chrome_video:
        image: selenium/video:ffmpeg-4.3.1-20210804
        volumes:
          - /Users/videos:/videos 
        depends_on:
          - chrome
        environment:
          - DISPLAY_CONTAINER_NAME=chrome
          - FILE_NAME=chrome_video.mp4

After containers start to work successfully, when I run npm run test for running selenium js tests, I got successful results and video recording in expected directory. But it should be automated as well. npm run test should be triggered somehow.

In our CI/CD process, cloudbuild.yaml file is added for running on cloud.

 steps:
   - name: 'docker/compose:1.29.2'
      args: ['run','test']

   - name: 'docker/compose:1.29.2'
      args: ['stop']
      timeout: 60s

Cloud build should trigger the new container below which is added to docker-compose file as test runner:

test:
    image:  node:16-alpine
    entrypoint:
    - sh
    - -c
    - |-
      cd /test
      npm install
      sleep 3
      npm run test
    volumes:
    - .:/test
    depends_on:
    - selenium
    network_mode: host

However with test container, tests are failed and get the error below:

24 packages are looking for funding


run `npm fund` for details


2 moderate severity vulnerabilities


To address all issues, run:

npm audit fix


Run `npm audit` for details.


> [email protected] test

> mocha test




Preliminary steps for End to End Tests

initalising the session...

1) Login

closing the session...

2) "after each" hook for "Login"



0 passing (108ms)

2 failing


1) Preliminary steps for End to End Tests

Login:

Error: ECONNREFUSED connect ECONNREFUSED 127.0.0.1:4444

at ClientRequest.<anonymous> (node_modules/selenium-webdriver/http/index.js:273:15)

at ClientRequest.emit (node:events:394:28)

at Socket.socketErrorListener (node:_http_client:447:9)

at Socket.emit (node:events:394:28)

at emitErrorNT (node:internal/streams/destroy:157:8)

at emitErrorCloseNT (node:internal/streams/destroy:122:3)

at processTicksAndRejections (node:internal/process/task_queues:83:21)


2) Preliminary steps for End to End Tests

"after each" hook for "Login":

Error: ECONNREFUSED connect ECONNREFUSED 127.0.0.1:4444

at ClientRequest.<anonymous> (node_modules/selenium-webdriver/http/index.js:273:15)

at ClientRequest.emit (node:events:394:28)

at Socket.socketErrorListener (node:_http_client:447:9)

at Socket.emit (node:events:394:28)

at emitErrorNT (node:internal/streams/destroy:157:8)

at emitErrorCloseNT (node:internal/streams/destroy:122:3)

at processTicksAndRejections (node:internal/process/task_queues:83:2

Containers:

CONTAINER ID   IMAGE                                                 COMMAND                   CREATED              STATUS              PORTS                                                      NAMES
7ca30366bc09   node:16-alpine                                        "sh -c 'cd /test\nnpm…"   About a minute ago   Up About a minute                                                              e2e-tests_test_1
fdf43be1b4da   selenium/video:ffmpeg-4.3.1-20210804                  "/opt/bin/entry_poin…"    16 minutes ago       Up About a minute   9000/tcp                                                   e2e-tests_chrome_video_1
92c023b15cb6   selenium/node-chrome:4.0.0-rc-1-prerelease-20210804   "/opt/bin/entry_poin…"    16 minutes ago       Up About a minute   0.0.0.0:6900->5900/tcp, :::6900->5900/tcp                  e2e-tests_chrome_1
86002f3d1eb9   selenium/hub:4.0.0-rc-1-prerelease-20210804           "/opt/bin/entry_poin…"    16 minutes ago       Up About a minute   4442-4443/tcp, 0.0.0.0:4444->4444/tcp, :::4444->4444/tcp   selenium-hub 

I can ping selenuim-hub from e2e-tests_test_1 container, but cannot do it reverse(ping e2e-tests_test_1 from selenium-hub).

About current network:

 >> % docker network inspect -v host
[
    {
        "Name": "host",
        "Id": "36e4060f18be618399692294d10cf6be3478c1bf5190ea035b002ca87c18276b",
        "Created": "2021-06-30T10:36:33.170635189Z",
        "Scope": "local",
        "Driver": "host",
        "EnableIPv6": false,
        "IPAM": {
            "Driver": "default",
            "Options": null,
            "Config": []
        },
        "Internal": false,
        "Attachable": false,
        "Ingress": false,
        "ConfigFrom": {
            "Network": ""
        },
        "ConfigOnly": false,
        "Containers": {},
        "Options": {},
        "Labels": {}
    }
]

It seems test node cannot reach to 127.0.0.1:4444

What should I do for solving this issue? It'd be good to hear alternative solutions.

Thanks in advance.

Answer 1

You need to wait for the Grid to be ready before running tests. I documented a few approaches for this on the project's README, please check https://github.com/seleniumhq/docker-selenium/#waiting-for-the-grid-to-be-ready