dockerselenium-grid

How to Set Capabilities on Node Browser with selenium Docker

I am new with selenium docker. I want to create a Chrome/Firefox node with capabilities (Selenium Grid). How to add capabilities when I add a Selenium Node docker container? I found this command so far...

 docker run -d --link selenium-hub:hub selenium/node-firefox:2.53.0

but I don't know how to add capabilities on it. Already use this command but not working.

 docker run -d --link selenium-hub:hub selenium/node-firefox:2.53.0 -browser browserName=firefox,version=3.6,maxInstances=5,platform=LINUX
Solution

  • There are multiple ways of doing this and SE_OPTS is one of them, however for me it complicated what I was trying to accomplish. Using SE_OPTS forced me to set capabilities I didn't want to change, otherwise they would be reset to blank/null

    I wanted to do:

    SE_OPTS=-browser applicationName=Testing123

    but I was forced to do:

    SE_OPTS=-browser applicationName=Testing123,browserName=firefox,maxInstances=1,version=59.0.1

    Another way to set capabilities is to supply your own config.json

    -nodeConfig /path/config.json

    You can find a default config.json

    Or you can start the node container and copy the current one from it

    docker cp <containerId>:/opt/selenium/config.json /host/path/target

    You can also take a look at entry_point.sh, either on github or on the running container:

    /opt/bin/entry_point.sh

    You can run bash on the node container via:

    sudo docker exec -i -t <container> bash

    This will let you see how SE_OPTS is used and how config.json is generated. Note config.json is generated only if you don't supply one.

    /opt/bin/generate_config

    By examining generate_config you can see quite a few ENV vars such as: FIREFOX_VERSION, NODE_MAX_INSTANCES, NODE_APPLICATION_NAME etc.

    This leads to the third way to set capabilities which is to set the environment variables being used by generate_config, in my case APPLICATION_NODE_NAME

    docker run -d -e "NODE_APPLICATION_NAME=Testing123"

    Finally, when using SE_OPTS be careful not to accidentally change values. Specifically, the browser version. You can see by looking at entry_point.sh the browser version is calculated. 

    FIREFOX_VERSION=$( firefox -version | cut -d " " -f 3 )

    If you change it to something else you will not get the results you are looking for.