5.3 KiB
Restore action
The restore action, as the name suggest, restores a cache. It acts similar to the cache
action except that it doesn't have a post step to save the cache. This action can provide you a granular control to only restore a cache without having to necessarily save it. It accepts the same set of inputs as the cache
action.
Inputs
path
- A list of files, directories, and wildcard patterns to cache and restore. See@actions/glob
for supported patterns.key
- String used while saving cache for restoring the cacherestore-keys
- An ordered list of prefix-matched keys to use for restoring stale cache if no cache hit occurred for key.fail-on-cache-miss
- Fail the workflow if cache entry is not found. Default: false
Outputs
cache-hit
- A boolean value to indicate an exact match was found for the key.cache-primary-key
- Cache primary key passed in the input to use in subsequent steps of the workflow.cache-matched-key
- Key of the cache that was restored, it could either be the primary key on cache-hit or a partial/complete match of one of the restore keys.
Note
cache-hit
will be set totrue
only when cache hit occurs for the exactkey
match. For a partial key match viarestore-keys
or a cache miss, it will be set tofalse
.
Environment Variables
SEGMENT_DOWNLOAD_TIMEOUT_MINS
- Segment download timeout (in minutes, default60
) to abort download of the segment if not completed in the defined number of minutes. Read more
Use cases
As this is a newly introduced action to give users more control in their workflows, below are some use cases where one can use this action.
Only restore cache
In case you are using another workflow to create and save your cache that can be reused by other jobs in your repository, this action will take care of your restore only needs.
steps:
- uses: actions/checkout@v3
- uses: actions/cache/restore@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
- name: Build
run: /build.sh
- name: Publish package to public
run: /publish.sh
Once the cache is restored, this action won't run any post step to do post-processing like actions/cache
and the rest of the workflow will run as usual.
Save intermediate private build artifacts
In case of multi-module projects, where the built artifact of one project needs to be reused in subsequent child modules, the need of rebuilding the parent module again and again with every build can be eliminated. The actions/cache
or actions/cache/save
action can be used to build and save the parent module artifact once, and restored multiple times while building the child modules.
Step 1 - Build the parent module and save it
steps:
- uses: actions/checkout@v3
- name: Build
run: /build-parent-module.sh
- uses: actions/cache/save@v3
id: cache
with:
path: path/to/dependencies
key: ${{ runner.os }}-${{ hashFiles('**/lockfiles') }}
Step 2 - Restore the built artifact from cache using the same key and path
steps:
- uses: actions/checkout@v3
- uses: actions/cache/restore@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
- name: Build
run: /build-child-module.sh
- name: Publish package to public
run: /publish.sh
Exit workflow on cache miss
You can use fail-on-cache-miss: true
to exit the workflow on a cache miss. This way you can restrict your workflow to only initiate the build when a cache is matched. Also, if you want to fail if cache did not match primary key, additionally leave restore-keys
empty!
steps:
- uses: actions/checkout@v3
- uses: actions/cache/restore@v3
id: cache
with:
path: path/to/dependencies
key: ${{ runner.os }}-${{ hashFiles('**/lockfiles') }}
fail-on-cache-miss: true
- name: Build
run: /build.sh
Tips
Reusing primary key and restored key in the save action
Usually you may want to use same key
in both actions/cache/restore
and actions/cache/save
action. To achieve this, use outputs
from the restore action to reuse the same primary key (or the key of the cache that was restored).
Using restore action outputs to make save action behave just like the cache action
The outputs cache-primary-key
and cache-matched-key
can be used to check if the restored cache is same as the given primary key. Alternatively, the cache-hit
output can also be used to check if the restored was a complete match or a partially restored cache.
Ensuring proper restores and save happen across the actions
It is very important to use the same key
and path
that were used by either actions/cache
or actions/cache/save
while saving the cache. Learn more about cache key naming and versioning here.