How to add an environment variable to a container in Docker Desktop?

In this article, we will guide you through the process of adding an environment variable to a container in Docker Desktop. Docker Desktop is a powerful tool that allows you to create and manage containers on your local machine.

What is an environment variable?

Before we dive into the process, let's first understand what an environment variable is. An environment variable is a dynamic value that can affect the behavior of a program or a process running on your computer. It is essentially a key-value pair that provides information to the program or process.

Step 1: Open Docker Desktop

The first step is to open Docker Desktop on your computer. Docker Desktop provides a user-friendly interface to manage your containers.

Step 2: Select the container

Once Docker Desktop is open, you will see a list of containers on the left-hand side. Select the container to which you want to add an environment variable.

Step 3: Open container settings

After selecting the container, you will see the container details on the right-hand side. Click on the "Settings" tab to open the container settings.

Step 4: Add environment variable

In the container settings, scroll down until you find the "Environment Variables" section. Here, you can add, edit, or remove environment variables for the selected container.

To add a new environment variable, click on the "Add Variable" button. This will open a dialog box where you can enter the key and value for the environment variable.

For example, let's say you want to add an environment variable called "API_KEY" with the value "123456789". In the dialog box, enter "API_KEY" in the "Key" field and "123456789" in the "Value" field. Then, click on the "Save" button to add the environment variable to the container.

Step 5: Apply changes

After adding the environment variable, you need to apply the changes to the container. Click on the "Apply & Restart" button to apply the changes and restart the container.

Once the container is restarted, it will have access to the environment variable you added. You can use this environment variable in your containerized application or process.

Step 6: Verify the environment variable

To verify that the environment variable has been successfully added to the container, you can open a terminal or command prompt inside the container and check the value of the environment variable.

For example, if you are using a Linux-based container, you can run the following command:

If the environment variable has been added correctly, you will see the value "123456789" printed on the terminal.

Conclusion

Adding an environment variable to a container in Docker Desktop is a simple process. By following the steps outlined in this article, you can easily add, edit, or remove environment variables for your containers.

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