This sub-action is a helper to merge multiple artifacts after they are created. To do so, it will download multiple artifacts to a temporary directory and reupload them as a single artifact.
For most cases, this may not be the most efficient solution. See [the migration docs](../docs/MIGRATION.md#multiple-uploads-to-the-same-named-artifact) on how to download multiple artifacts to the same directory on a runner. This action should only be necessary for cases where multiple artifacts will need to be downloaded outside the runner environment, like downloads via the UI or REST API.
# If true, the artifacts will be merged into separate directories.
# If false, the artifacts will be merged into the root of the destination.
# Optional. Default is 'false'
separate-directories:
# If true, the artifacts that were merged will be deleted.
# If false, the artifacts will still exist.
# Optional. Default is 'false'
delete-merged:
# Duration after which artifact will expire in days. 0 means using default retention.
# Minimum 1 day.
# Maximum 90 days unless changed from the repository settings page.
# Optional. Defaults to repository settings.
retention-days:
# The level of compression for Zlib to be applied to the artifact archive.
# The value can range from 0 to 9.
# For large files that are not easily compressed, a value of 0 is recommended for significantly faster uploads.
# Optional. Default is '6'
compression-level:
```
### Outputs
| Name | Description | Example |
| - | - | - |
| `artifact-id` | GitHub ID of an Artifact, can be used by the REST API | `1234` |
| `artifact-url` | URL to download an Artifact. Can be used in many scenarios such as linking to artifacts in issues or pull requests. Users must be logged-in in order for this URL to work. This URL is valid as long as the artifact has not expired or the artifact, run or repository have not been deleted | `https://github.com/example-org/example-repo/actions/runs/1/artifacts/1234` |
Each of the following examples will use the `needs: upload` as a prerequesite before any merging operations.
### Combining all artifacts in a workflow run
By default (with no inputs), calling this action will take all the artifacts in the workflow run and combined them into a single artifact called `merged-artifacts`:
```yaml
jobs:
# ... <uploadjob> ...
merge:
runs-on: ubuntu-latest
needs: upload
steps:
- name: Merge Artifacts
uses: actions/upload-artifact/merge@v4
```
This will result in an artifact called `merged-artifacts` with the following content:
```
.
∟ file-a.txt
∟ file-b.txt
∟ file-c.txt
```
To change the name of the artifact and filter on what artifacts are added, you can use the `name` and `pattern` inputs:
```yaml
jobs:
# ... <uploadjob> ...
merge:
runs-on: ubuntu-latest
needs: upload
steps:
- name: Merge Artifacts
uses: actions/upload-artifact/merge@v4
with:
name: my-amazing-merged-artifact
pattern: my-artifact-*
```
### Prefix directories in merged artifact
To prevent overwriting files in artifacts that may have the same name, you can use the `separate-directories` to prefix the extracted files with directories (named after the original artifact):
```yaml
jobs:
# ... <uploadjob> ...
merge:
runs-on: ubuntu-latest
needs: upload
steps:
- name: Merge Artifacts
uses: actions/upload-artifact/merge@v4
with:
separate-directories: true
```
This will result in the following artifact structure:
```
.
∟ my-artifact-a
∟ file-a.txt
∟ my-artifact-b
∟ file-b.txt
∟ my-artifact-c
∟ file-c.txt
```
### Deleting artifacts after merge
After merge, the old artifacts may no longer be required. To automatically delete them after they are merged into a new artifact, you can use `delete-merged` like so:
```yaml
jobs:
# ... <uploadjob> ...
merge:
runs-on: ubuntu-latest
needs: upload
steps:
- name: Merge Artifacts
uses: actions/upload-artifact/merge@v4
with:
delete-merged: true
```
After this runs, the matching artifact (`my-artifact-a`, `my-artifact-b` and `my-artifact-c`) will be merged.
### Retention and Compression Level
Similar to actions/upload-artifact, both [`retention-days`](../README.md#retention-period) and [`compression-level`](../README.md#altering-compressions-level-speed-v-size) are supported:
