cache/README.md
Sampark Sharma 438628ac22
Merge pull request #554 from albertstill/improve-restore-key-docs
Improve restore-key documentation
2022-06-06 17:29:02 +05:30

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7.9 KiB
Markdown

# cache
This action allows caching dependencies and build outputs to improve workflow execution time.
[![Tests](https://github.com/actions/cache/actions/workflows/workflow.yml/badge.svg)](https://github.com/actions/cache/actions/workflows/workflow.yml)
## Documentation
See ["Caching dependencies to speed up workflows"](https://help.github.com/github/automating-your-workflow-with-github-actions/caching-dependencies-to-speed-up-workflows).
## What's New
### v3
* Added support for caching from GHES 3.5.
* Fixed download issue for files > 2GB during restore.
* Updated the minimum runner version support from node 12 -> node 16.
* Fixed avoiding empty cache save when no files are available for caching.
Refer [here](https://github.com/actions/cache/blob/v2/README.md) for previous versions
## Usage
### Pre-requisites
Create a workflow `.yml` file in your repositories `.github/workflows` directory. An [example workflow](#example-workflow) is available below. For more information, reference the GitHub Help Documentation for [Creating a workflow file](https://help.github.com/en/articles/configuring-a-workflow#creating-a-workflow-file).
If you are using this inside a container, a POSIX-compliant `tar` needs to be included and accessible in the execution path.
### Inputs
* `path` - A list of files, directories, and wildcard patterns to cache and restore. See [`@actions/glob`](https://github.com/actions/toolkit/tree/main/packages/glob) for supported patterns.
* `key` - An explicit key for restoring and saving the cache
* `restore-keys` - An ordered list of keys to use for restoring stale cache if no cache hit occurred for key. Note
`cache-hit` returns false in this case.
### Outputs
* `cache-hit` - A boolean value to indicate an exact match was found for the key
> See [Skipping steps based on cache-hit](#Skipping-steps-based-on-cache-hit) for info on using this output
### Cache scopes
The cache is scoped to the key and branch. The default branch cache is available to other branches.
See [Matching a cache key](https://help.github.com/en/actions/configuring-and-managing-workflows/caching-dependencies-to-speed-up-workflows#matching-a-cache-key) for more info.
### Example workflow
```yaml
name: Caching Primes
on: push
jobs:
build:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v3
- name: Cache Primes
id: cache-primes
uses: actions/cache@v3
with:
path: prime-numbers
key: ${{ runner.os }}-primes
- name: Generate Prime Numbers
if: steps.cache-primes.outputs.cache-hit != 'true'
run: /generate-primes.sh -d prime-numbers
- name: Use Prime Numbers
run: /primes.sh -d prime-numbers
```
## Implementation Examples
Every programming language and framework has its own way of caching.
See [Examples](examples.md) for a list of `actions/cache` implementations for use with:
- [C# - NuGet](./examples.md#c---nuget)
- [D - DUB](./examples.md#d---dub)
- [Deno](./examples.md#deno)
- [Elixir - Mix](./examples.md#elixir---mix)
- [Go - Modules](./examples.md#go---modules)
- [Haskell - Cabal](./examples.md#haskell---cabal)
- [Haskell - Stack](./examples.md#haskell---stack)
- [Java - Gradle](./examples.md#java---gradle)
- [Java - Maven](./examples.md#java---maven)
- [Node - npm](./examples.md#node---npm)
- [Node - Lerna](./examples.md#node---lerna)
- [Node - Yarn](./examples.md#node---yarn)
- [OCaml/Reason - esy](./examples.md#ocamlreason---esy)
- [PHP - Composer](./examples.md#php---composer)
- [Python - pip](./examples.md#python---pip)
- [Python - pipenv](./examples.md#python---pipenv)
- [R - renv](./examples.md#r---renv)
- [Ruby - Bundler](./examples.md#ruby---bundler)
- [Rust - Cargo](./examples.md#rust---cargo)
- [Scala - SBT](./examples.md#scala---sbt)
- [Swift, Objective-C - Carthage](./examples.md#swift-objective-c---carthage)
- [Swift, Objective-C - CocoaPods](./examples.md#swift-objective-c---cocoapods)
- [Swift - Swift Package Manager](./examples.md#swift---swift-package-manager)
## Creating a cache key
A cache key can include any of the contexts, functions, literals, and operators supported by GitHub Actions.
For example, using the [`hashFiles`](https://help.github.com/en/actions/reference/context-and-expression-syntax-for-github-actions#hashfiles) function allows you to create a new cache when dependencies change.
```yaml
- uses: actions/cache@v3
with:
path: |
path/to/dependencies
some/other/dependencies
key: ${{ runner.os }}-${{ hashFiles('**/lockfiles') }}
```
Additionally, you can use arbitrary command output in a cache key, such as a date or software version:
```yaml
# http://man7.org/linux/man-pages/man1/date.1.html
- name: Get Date
id: get-date
run: |
echo "::set-output name=date::$(/bin/date -u "+%Y%m%d")"
shell: bash
- uses: actions/cache@v3
with:
path: path/to/dependencies
key: ${{ runner.os }}-${{ steps.get-date.outputs.date }}-${{ hashFiles('**/lockfiles') }}
```
See [Using contexts to create cache keys](https://help.github.com/en/actions/configuring-and-managing-workflows/caching-dependencies-to-speed-up-workflows#using-contexts-to-create-cache-keys)
## Cache Limits
A repository can have up to 10GB of caches. Once the 10GB limit is reached, older caches will be evicted based on when the cache was last accessed. Caches that are not accessed within the last week will also be evicted.
## Skipping steps based on cache-hit
Using the `cache-hit` output, subsequent steps (such as install or build) can be skipped when a cache hit occurs on the key.
Example:
```yaml
steps:
- uses: actions/checkout@v3
- uses: actions/cache@v3
id: cache
with:
path: path/to/dependencies
key: ${{ runner.os }}-${{ hashFiles('**/lockfiles') }}
- name: Install Dependencies
if: steps.cache.outputs.cache-hit != 'true'
run: /install.sh
```
> Note: The `id` defined in `actions/cache` must match the `id` in the `if` statement (i.e. `steps.[ID].outputs.cache-hit`)
## Cache Version
Cache version is unique for a combination of compression tool used for compression of cache (Gzip, Zstd, etc based on runner OS) and the path of directories being cached. If two caches have different versions, they are identified as unique cache entries. This also means that a cache created on `windows-latest` runner can't be restored on `ubuntu-latest` as cache `Version`s are different.
Example: Below example will create 3 unique caches with same keys. Ubuntu and windows runners will use different compression technique and hence create two different caches. And `build-linux` will create two different caches as the `paths` are different.
```yaml
jobs:
build-linux:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v3
- name: Cache Primes
id: cache-primes
uses: actions/cache@v3
with:
path: prime-numbers
key: primes
- name: Generate Prime Numbers
if: steps.cache-primes.outputs.cache-hit != 'true'
run: ./generate-primes.sh -d prime-numbers
- name: Cache Numbers
id: cache-numbers
uses: actions/cache@v3
with:
path: numbers
key: primes
- name: Generate Numbers
if: steps.cache-numbers.outputs.cache-hit != 'true'
run: ./generate-primes.sh -d numbers
build-windows:
runs-on: windows-latest
steps:
- uses: actions/checkout@v3
- name: Cache Primes
id: cache-primes
uses: actions/cache@v3
with:
path: prime-numbers
key: primes
- name: Generate Prime Numbers
if: steps.cache-primes.outputs.cache-hit != 'true'
run: ./generate-primes -d prime-numbers
```
## Contributing
We would love for you to contribute to `actions/cache`, pull requests are welcome! Please see the [CONTRIBUTING.md](CONTRIBUTING.md) for more information.
## License
The scripts and documentation in this project are released under the [MIT License](LICENSE)