docker-build-push/docs/advanced/export-docker.md

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# Export image to Docker
You may want your build result to be available in the Docker client through `docker images` to be able to use it
in another step of your workflow:
```yaml
name: ci
on:
push:
branches:
- 'main'
jobs:
docker:
runs-on: ubuntu-latest
steps:
-
name: Checkout
uses: actions/checkout@v3
-
name: Set up Docker Buildx
uses: docker/setup-buildx-action@v2
-
name: Build
uses: docker/build-push-action@v3
with:
context: .
load: true
tags: myimage:latest
-
name: Inspect
run: |
docker image inspect myimage:latest
```
## Usage of the built image in other build steps
[By default](https://github.com/docker/setup-buildx-action#customizing), `docker/setup-buildx-action@v2`
uses `docker-container` as a build driver, so the docker images are not available in the builder container.
To use them, you may use [build contexts](https://github.com/docker/buildx/blob/master/docs/reference/buildx_build.md#-additional-build-contexts---build-context):
```yaml
name: ci
on:
push:
branches:
- 'main'
jobs:
docker:
runs-on: ubuntu-latest
steps:
-
name: Checkout
uses: actions/checkout@v3
-
name: Set up Docker Buildx
uses: docker/setup-buildx-action@v2
-
name: Build base image
uses: docker/build-push-action@v3
with:
context: base
load: true
tags: my-base-image:latest
-
name: Build image from my-base-image:latest
uses: docker/build-push-action@v3
with:
context: .
build-contexts: |
base-image=docker-image://my-base-image:latest
tags: myimage:latest
```
Where `base-image`is the name of the base image (or stage name if specified) in your Dockerfile:
```Dockerfile
FROM base-image
```
### Bake alternative
You may also want to use [bake](https://docs.docker.com/build/bake/build-contexts/#using-a-result-of-one-target-as-a-base-image-in-another-target)
and build the base image and the target image in one build step:
```terraform
# docker-bake.hcl
target "base" {
dockerfile = "baseapp.Dockerfile"
}
target "app" {
contexts = {
baseapp = "target:base"
}
}
```
```yaml
-
name: Build
uses: docker/bake-action@v2
with:
target: app
```