docs/content/build/cache/backends/gha.md

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---
title: GitHub Actions cache
description: Use the GitHub Actions cache to manage your build cache in CI
keywords: build, buildx, cache, backend, gha, github, actions
aliases:
- /build/building/cache/backends/gha/
---
> **Experimental**
>
> This is an experimental feature. The interface and behavior are unstable and
> may change in future releases.
{ .restricted }
The GitHub Actions cache utilizes the
[GitHub-provided Action's cache](https://github.com/actions/cache) or other
cache services supporting the GitHub Actions cache protocol. This is the
recommended cache to use inside your GitHub Actions workflows, as long as your
use case falls within the
[size and usage limits set by GitHub](https://docs.github.com/en/actions/using-workflows/caching-dependencies-to-speed-up-workflows#usage-limits-and-eviction-policy).
This cache storage backend is not supported with the default `docker` driver.
To use this feature, create a new builder using a different driver. See
[Build drivers](../../drivers/_index.md) for more information.
## Synopsis
```console
$ docker buildx build --push -t <registry>/<image> \
--cache-to type=gha[,parameters...] \
--cache-from type=gha[,parameters...] .
```
The following table describes the available CSV parameters that you can pass to
`--cache-to` and `--cache-from`.
| Name | Option | Type | Default | Description |
| -------------- | ----------------------- | ----------- | ------------------------ | -------------------------------------------------------------------- |
| `url` | `cache-to`,`cache-from` | String | `$ACTIONS_CACHE_URL` | Cache server URL, see [authentication][1]. |
| `token` | `cache-to`,`cache-from` | String | `$ACTIONS_RUNTIME_TOKEN` | Access token, see [authentication][1]. |
| `scope` | `cache-to`,`cache-from` | String | `buildkit` | Which scope cache object belongs to, see [scope][2] |
| `mode` | `cache-to` | `min`,`max` | `min` | Cache layers to export, see [cache mode][3]. |
| `ignore-error` | `cache-to` | Boolean | `false` | Ignore errors caused by failed cache exports. |
| `timeout` | `cache-to`,`cache-from` | String | `10m` | Max duration for importing or exporting cache before it's timed out. |
[1]: #authentication
[2]: #scope
[3]: _index.md#cache-mode
## Authentication
If the `url` or `token` parameters are left unspecified, the `gha` cache backend
will fall back to using environment variables. If you invoke the `docker buildx`
command manually from an inline step, then the variables must be manually
exposed. Consider using the
[`crazy-max/ghaction-github-runtime`](https://github.com/crazy-max/ghaction-github-runtime),
GitHub Action as a helper for exposing the variables.
## Scope
Scope is a key used to identify the cache object. By default, it is set to
`buildkit`. If you build multiple images, each build will overwrite the cache
of the previous, leaving only the final cache.
To preserve the cache for multiple builds, you can specify this scope attribute
with a specific name. In the following example, the cache is set to the image
name, to ensure each image gets its own cache:
```console
$ docker buildx build --push -t <registry>/<image> \
--cache-to type=gha,url=...,token=...,scope=image \
--cache-from type=gha,url=...,token=...,scope=image .
$ docker buildx build --push -t <registry>/<image2> \
--cache-to type=gha,url=...,token=...,scope=image2 \
--cache-from type=gha,url=...,token=...,scope=image2 .
```
GitHub's [cache access restrictions](https://docs.github.com/en/actions/advanced-guides/caching-dependencies-to-speed-up-workflows#restrictions-for-accessing-a-cache),
still apply. Only the cache for the current branch, the base branch and the
default branch is accessible by a workflow.
### Using `docker/build-push-action`
When using the
[`docker/build-push-action`](https://github.com/docker/build-push-action), the
`url` and `token` parameters are automatically populated. No need to manually
specify them, or include any additional workarounds.
For example:
```yaml
- name: Build and push
uses: docker/build-push-action@v5
with:
context: .
push: true
tags: "<registry>/<image>:latest"
cache-from: type=gha
cache-to: type=gha,mode=max
```
## Further reading
For an introduction to caching see [Docker build cache](../_index.md).
For more information on the `gha` cache backend, see the
[BuildKit README](https://github.com/moby/buildkit#github-actions-cache-experimental).
For more information about using GitHub Actions with Docker, see
[Introduction to GitHub Actions](../../ci/github-actions/_index.md)