How to use docker build

The docker build command is used to build Docker images from a Dockerfile. Let's cover the essential usage and most important options.

Basic Usage

The basic syntax is:

docker build [OPTIONS] PATH | URL | -

This tells Docker to build an image using the Dockerfile in the specified PATH or URL. The . at the end means "current directory".

Most Important Options

Here are the most commonly used options:

-t, --tag

Tag your image (give it a name):

docker build -t myapp:latest .

-f, --file

Specify a different Dockerfile name:

docker build -f custom.Dockerfile .

--no-cache

Force a fresh build without using cached layers:

docker build --no-cache .

--build-arg

Pass variables to the build process:

docker build --build-arg VERSION=1.0 .

--platform

Build for specific platforms:

docker build --platform linux/amd64,linux/arm64 .

--pull

Always pull the latest base images:

docker build --pull .

Common Use Cases

1. Basic build with tag:

docker build -t myapp:1.0 .

2. Build with multiple tags:

docker build -t myapp:latest -t myapp:1.0 .

3. Build with build arguments:

docker build --build-arg ENV=production -t myapp:prod .

Conclusion

While docker build has many options, these are the ones you'll use most often. They cover the essential needs for building Docker images: naming your images, specifying build variables, and controlling the build cache.