Скачать или смотреть How to Easily Get the Container Name in a Dockerfile

Discover a simple way to retrieve the `container name` from your Dockerfile using the `.env` file and docker-compose settings!
---
This video is based on the question https://stackoverflow.com/q/63137713/ asked by the user 'Samir Guiderk' ( https://stackoverflow.com/u/9048371/ ) and on the answer https://stackoverflow.com/a/63138255/ provided by the user 'Omer Tuchfeld' ( https://stackoverflow.com/u/791430/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Get container name in dockerfile

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
How to Easily Get the Container Name in a Dockerfile

When working with Docker, every container runs its own isolated environment, but sometimes you might need to reference the name of your container within a Dockerfile for various reasons, like file management or configuration. However, the container name is not directly accessible from within the Dockerfile. Fortunately, there's a straightforward workaround that allows you to define your container's name in a single place and utilize that information inside both your docker-compose.yml and Dockerfile. Let’s explore how to implement this solution effectively.

The Problem: Accessing the Container Name

You want to retrieve the container name (in this case, php_web) inside your Dockerfile for the PHP application you are building. Since Dockerfiles do not have direct access to their container names, we need to employ an alternative approach.

The Solution: Using an .env File

Step 1: Create an .env file

Create a new file named .env in the same directory as your docker-compose.yml file.

Define the container name in the .env file as follows:

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Modify your docker-compose.yml file

You will need to modify your existing docker-compose.yml to include the reference to the container name defined in your .env file.

Locate the service section for your web application, and change it as follows:

[[See Video to Reveal this Text or Code Snippet]]

Here, ${APP_CONTAINER_NAME} retrieves the value defined in the .env file and uses it for both the container_name and as a build argument.

Step 3: Update the Dockerfile

Inside your php-app/Dockerfile, you must add an argument declaration to access the value set in the .env file.

Introduce the argument towards the top of your Dockerfile:

[[See Video to Reveal this Text or Code Snippet]]

Step 4: Utilize the Container Name

Now that you have access to the container name, you can use it within the Dockerfile for tasks such as creating files or directories. For example, if you want to create a file named after the container, you can add the following line in your Dockerfile:

[[See Video to Reveal this Text or Code Snippet]]

This command creates a file inside the container with the same name as the container itself.

Conclusion

By following these simple steps, you can efficiently manage and use your container's name within your Dockerfiles. Utilizing an .env file helps maintain a clean codebase while avoiding hardcoding container names throughout your configurations. The workaround not only streamlines your setup process but also enhances maintainability. We hope this guide helps simplify your Docker development experience! Happy coding!