Bake is an abstraction for the docker build
command that lets you more easily
manage your build configuration (CLI flags, environment variables, etc.) in a
consistent way for everyone on your team.
Bake is a command built into the Buildx CLI, so as long as you have Buildx
installed, you also have access to bake, via the docker buildx bake
command.
Building a project with Bake#
Here's a simple example of a docker build
command:
$ docker build -f Dockerfile -t myapp:latest .
This command builds the Dockerfile in the current directory and tags the
resulting image as myapp:latest
.
To express the same build configuration using Bake:
```hcl {title=docker-bake.hcl} target "myapp" { context = "." dockerfile = "Dockerfile" tags = ["myapp:latest"] }
Bake provides a structured way to manage your build configuration, and it saves
you from having to remember all the CLI flags for `docker build` every time.
With this file, building the image is as simple as running:
```console
$ docker buildx bake myapp
For simple builds, the difference between docker build
and docker buildx
bake
is minimal. However, as your build configuration grows more complex, Bake
provides a more structured way to manage that complexity, that would be
difficult to manage with CLI flags for the docker build
. It also provides a
way to share build configurations across your team, so that everyone is
building images in a consistent way, with the same configuration.
The Bake file format#
You can write Bake files in HCL, YAML (Docker Compose files), or JSON. In general, HCL is the most expressive and flexible format, which is why you'll see it used in most of the examples in this documentation, and in projects that use Bake.
The properties that can be set for a target closely resemble the CLI flags for
docker build
. For instance, consider the following docker build
command:
$ docker build \
-f Dockerfile \
-t myapp:latest \
--build-arg foo=bar \
--no-cache \
--platform linux/amd64,linux/arm64 \
.
The Bake equivalent would be:
target "myapp" {
context = "."
dockerfile = "Dockerfile"
tags = ["myapp:latest"]
args = {
foo = "bar"
}
no-cache = true
platforms = ["linux/amd64", "linux/arm64"]
}
Next steps#
To learn more about using Bake, see the following topics:
- Learn how to define and use targets in Bake
- To see all the properties that can be set for a target, refer to the Bake file reference.