Executing Commands in Docker Containers

Executing a command in a Docker Container can be beneficial in many ways to DevOps teams. Docker can dynamically provide very specific environments which allow for controlled testing and execution of commands. In this solution example we will run a simple command in a Docker Image.

Pre-requisites & Environment Setup

• For ease of testing, have an Enterprise Runner running on the same host that is running Docker and use the Automatic Runner Dispatch setup.
• Must setup Docker Node Source before running this job.
• The example job assumes the base OS of Docker image is Linux based.

Setting up Docker Node Source

1. Open the Example Content project.
2. Navigate to Project Settings > Edit Nodes
3. Click Add A Node Source
4. Choose the docker / container / model entry.
5. Specify your Runner and Save.

More specifics about setting up this Node Source can be found on it's documentation page here.

Running the Job

Tips

To find the Docker jobs quickly in the job listing click on the docker tag at the top of the list.

The default node filter for this job is tags: "docker". Nodes discovered by the Docker node source above will automatically get this tag assigned to them. If you'd like to run the job on a particular container select it from the list.

The default command will run ls -last on any container in the target list along with the other steps in the job definition.

Run Job Screen

Here is some example output

Example Output