## File: README.md

# `@actions/upload-artifact`

> [!WARNING]
> actions/upload-artifact@v3 is scheduled for deprecation on **November 30, 2024**. [Learn more.](https://github.blog/changelog/2024-04-16-deprecation-notice-v3-of-the-artifact-actions/)
> Similarly, v1/v2 are scheduled for deprecation on **June 30, 2024**.
> Please update your workflow to use v4 of the artifact actions.
> This deprecation will not impact any existing versions of GitHub Enterprise Server being used by customers.

Upload [Actions Artifacts](https://docs.github.com/en/actions/using-workflows/storing-workflow-data-as-artifacts) from your Workflow Runs. Internally powered by [@actions/artifact](https://github.com/actions/toolkit/tree/main/packages/artifact) package.

See also [download-artifact](https://github.com/actions/download-artifact).

- [`@actions/upload-artifact`](#actionsupload-artifact)
  - [What's new](#whats-new)
  - [GHES Support](#ghes-support)
  - [Usage](#usage)
    - [Inputs](#inputs)
    - [Outputs](#outputs)
  - [Examples](#examples)
    - [Upload an Individual File (Zipped)](#upload-an-individual-file-zipped)
    - [Upload an Individual File (Unzipped)](#upload-an-individual-file-unzipped)
    - [Upload an Entire Directory](#upload-an-entire-directory)
    - [Upload using a Wildcard Pattern](#upload-using-a-wildcard-pattern)
    - [Upload using Multiple Paths and Exclusions](#upload-using-multiple-paths-and-exclusions)
    - [Altering compressions level (speed v. size)](#altering-compressions-level-speed-v-size)
    - [Customization if no files are found](#customization-if-no-files-are-found)
    - [(Not) Uploading to the same artifact](#not-uploading-to-the-same-artifact)
    - [Environment Variables and Tilde Expansion](#environment-variables-and-tilde-expansion)
    - [Retention Period](#retention-period)
    - [Using Outputs](#using-outputs)
      - [Example output between steps](#example-output-between-steps)
      - [Example output between jobs](#example-output-between-jobs)
    - [Overwriting an Artifact](#overwriting-an-artifact)
  - [Limitations](#limitations)
    - [Number of Artifacts](#number-of-artifacts)
    - [Permission Loss](#permission-loss)
  - [Where does the upload go?](#where-does-the-upload-go)

## What's new

Check out the [releases page](https://github.com/actions/upload-artifact/releases) for details on what's new.

## Note

Thank you for your interest in this GitHub repo, however, right now we are not taking contributions.

We continue to focus our resources on strategic areas that help our customers be successful while making developers' lives easier. While GitHub Actions remains a key part of this vision, we are allocating resources towards other areas of Actions and are not taking contributions to this repository at this time. The GitHub public roadmap is the best place to follow along for any updates on features we’re working on and what stage they’re in.

We are taking the following steps to better direct requests related to GitHub Actions, including:

1. We will be directing questions and support requests to our [Community Discussions area](https://github.com/orgs/community/discussions/categories/actions)

2. High Priority bugs can be reported through Community Discussions or you can report these to our support team https://support.github.com/contact/bug-report.

3. Security Issues should be handled as per our [security.md](SECURITY.md).

We will still provide security updates for this project and fix major breaking changes during this time.

You are welcome to still raise bugs in this repo.

## GHES Support

`upload-artifact@v4+` is not currently supported on GitHub Enterprise Server (GHES). If you are on GHES, you must use [v3.2.2](https://github.com/actions/upload-artifact/releases/tag/v3.2.2) (Node 24) or [v3.2.2-node20](https://github.com/actions/upload-artifact/releases/tag/v3.2.2-node20) (Node 20).

## Usage

### Inputs

```
/* Detailed source-code truncated for AI context efficiency. */
```

### 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` |
| `artifact-digest` | SHA-256 digest of an Artifact | 0fde654d4c6e659b45783a725dc92f1bfb0baa6c2de64b34e814dc206ff4aaaf |

## Examples

### Upload an Individual File (Zipped)

```yaml
steps:
- run: mkdir -p path/to/artifact
- run: echo hello > path/to/artifact/world.txt
- uses: actions/upload-artifact@v7
  with:
    name: my-artifact
    path: path/to/artifact/world.txt
```

### Upload an Individual File (Unzipped)

```yaml
steps:
- run: mkdir -p path/to/artifact
- run: echo hello > path/to/artifact/world.txt
- uses: actions/upload-artifact@v7
  with:
    path: path/to/artifact/world.txt
    archive: false
```

### Upload an Entire Directory

```yaml
- uses: actions/upload-artifact@v7
  with:
    name: my-artifact
    path: path/to/artifact/ # or path/to/artifact
```

### Upload using a Wildcard Pattern

```yaml
- uses: actions/upload-artifact@v7
  with:
    name: my-artifact
    path: path/**/[abc]rtifac?/*
```

### Upload using Multiple Paths and Exclusions

```yaml
- uses: actions/upload-artifact@v7
  with:
    name: my-artifact
    path: |
      path/output/bin/
      path/output/test-results
      !path/**/*.tmp
```

For supported wildcards along with behavior and documentation, see [@actions/glob](https://github.com/actions/toolkit/tree/main/packages/glob) which is used internally to search for files.

If a wildcard pattern is used, the path hierarchy will be preserved after the first wildcard pattern:

```
path/to/*/directory/foo?.txt =>
    ∟ path/to/some/directory/foo1.txt
    ∟ path/to/some/directory/foo2.txt
    ∟ path/to/other/directory/foo1.txt

would be flattened and uploaded as =>
    ∟ some/directory/foo1.txt
    ∟ some/directory/foo2.txt
    ∟ other/directory/foo1.txt
```

If multiple paths are provided as input, the least common ancestor of all the search paths will be used as the root directory of the artifact. Exclude paths do not affect the directory structure.

Relative and absolute file paths are both allowed. Relative paths are rooted against the current working directory. Paths that begin with a wildcard character should be quoted to avoid being interpreted as YAML aliases.

### Altering compressions level (speed v. size)

If you are uploading large or easily compressable data to your artifact, you may benefit from tweaking the compression level. By default, the compression level is `6`, the same as GNU Gzip.

The value can range from 0 to 9:
  - 0: No compression
  - 1: Best speed
  - 6: Default compression (same as GNU Gzip)
  - 9: Best compression

Higher levels will result in better compression, but will take longer to complete.
For large files that are not easily compressed, a value of `0` is recommended for significantly faster uploads.

For instance, if you are uploading random binary data, you can save a lot of time by opting out of compression completely, since it won't benefit:

```yaml
- name: Make a 1GB random binary file
  run: |
    dd if=/dev/urandom of=my-1gb-file bs=1M count=1000
- uses: actions/upload-artifact@v7
  with:
    name: my-artifact
    path: my-1gb-file
    compression-level: 0 # no compression
```

But, if you are uploading data that is easily compressed (like plaintext, code, etc) you can save space and cost by having a higher compression level. But this will be heavier on the CPU therefore slower to upload:

```yaml
- name: Make a file with a lot of repeated text
  run: |
    for i in {1..100000}; do echo -n 'foobar' >> foobar.txt; done
- uses: actions/upload-artifact@v7
  with:
    name: my-artifact
    path: foobar.txt
    compression-level: 9 # maximum compression
```

### Customization if no files are found

If a path (or paths), result in no files being found for the artifact, the action will succeed but print out a warning. In certain scenarios it may be desirable to fail the action or suppress the warning. The `if-no-files-found` option allows you to customize the behavior of the action if no files are found:

```yaml
- uses: actions/upload-artifact@v7
  with:
    name: my-artifact
    path: path/to/artifact/
    if-no-files-found: error # 'warn' or 'ignore' are also available, defaults to `warn`
```

### (Not) Uploading to the same artifact

Unlike earlier versions of `upload-artifact`, uploading to the same artifact via multiple jobs is _not_ supported with `v4`.

```yaml
- run: echo hi > world.txt
- uses: actions/upload-artifact@v7
  with:
    # implicitly named as 'artifact'
    path: world.txt

- run: echo howdy > extra-file.txt
- uses: actions/upload-artifact@v7
  with:
    # also implicitly named as 'artifact', will fail here!
    path: extra-file.txt
```

Artifact names must be unique since each created artifact is idempotent so multiple jobs cannot modify the same artifact.

In matrix scenarios, be careful to not accidentally upload to the same artifact, or else you will encounter conflict errors. It would be best to name the artifact _with_ a prefix or suffix from the matrix:

```yaml
jobs:
  upload:
    name: Generate Build Artifacts

    strategy:
      matrix:
        os: [ubuntu-latest, windows-latest]
        version: [a, b, c]

    runs-on: ${{ matrix.os }}

    steps:
    - name: Build
      run: ./some-script --version=${{ matrix.version }} > my-binary
    - name: Upload
      uses: actions/upload-artifact@v7
      with:
        name: binary-${{ matrix.os }}-${{ matrix.version }}
        path: my-binary
```

This will result in artifacts like: `binary-ubuntu-latest-a`, `binary-windows-latest-b`, and so on.

Previously the behavior _allowed_ for the artifact names to be the same which resulted in unexpected mutations and accidental corruption. Artifacts created by upload-artifact@v4 are immutable.

### Environment Variables and Tilde Expansion

You can use `~` in the path input as a substitute for `$HOME`. Basic tilde expansion is supported:

```yaml
  - run: |
      mkdir -p ~/new/artifact
      echo hello > ~/new/artifact/world.txt
  - uses: actions/upload-artifact@v7
    with:
      name: my-artifacts
      path: ~/new/**/*
```

Environment variables along with context expressions can also be used for input. For documentation see [context and expression syntax](https://help.github.com/en/actions/reference/context-and-expression-syntax-for-github-actions):

```yaml
    env:
      name: my-artifact
    steps:
    - run: |
        mkdir -p ${{ github.workspace }}/artifact
        echo hello > ${{ github.workspace }}/artifact/world.txt
    - uses: actions/upload-artifact@v7
      with:
        name: ${{ env.name }}-name
        path: ${{ github.workspace }}/artifact/**/*
```

For environment variables created in other steps, make sure to use the `env` expression syntax

```yaml
    steps:
    - run: |
        mkdir testing
        echo "This is a file to upload" > testing/file.txt
        echo "artifactPath=testing/file.txt" >> $GITHUB_ENV
    - uses: actions/upload-artifact@v7
      with:
        name: artifact
        path: ${{ env.artifactPath }} # this will resolve to testing/file.txt at runtime
```

### Retention Period

Artifacts are retained for 90 days by default. You can specify a shorter retention period using the `retention-days` input:

```yaml
  - name: Create a file
    run: echo "I won't live long" > my_file.txt

  - name: Upload Artifact
    uses: actions/upload-artifact@v7
    with:
      name: my-artifact
      path: my_file.txt
      retention-days: 5
```

The retention period must be between 1 and 90 inclusive. For more information see [artifact and log retention policies](https://docs.github.com/en/free-pro-team@latest/actions/reference/usage-limits-billing-and-administration#artifact-and-log-retention-policy).

### Using Outputs

If an artifact upload is successful then an `artifact-id` output is available. This ID is a unique identifier that can be used with [Artifact REST APIs](https://docs.github.com/en/rest/actions/artifacts).

#### Example output between steps

```yml
    - uses: actions/upload-artifact@v7
      id: artifact-upload-step
      with:
        name: my-artifact
        path: path/to/artifact/content/

    - name: Output artifact ID
      run:  echo 'Artifact ID is ${{ steps.artifact-upload-step.outputs.artifact-id }}'
```

#### Example output between jobs

```yml
jobs:
  job1:
    runs-on: ubuntu-latest
    outputs:
      output1: ${{ steps.artifact-upload-step.outputs.artifact-id }}
    steps:
      - uses: actions/upload-artifact@v7
        id: artifact-upload-step
        with:
          name: my-artifact
          path: path/to/artifact/content/
  job2:
    runs-on: ubuntu-latest
    needs: job1
    steps:
      - env:
          OUTPUT1: ${{needs.job1.outputs.output1}}
        run: echo "Artifact ID from previous job is $OUTPUT1"
```

### Overwriting an Artifact

Although it's not possible to mutate an Artifact, can completely overwrite one. But do note that this will give the Artifact a new ID, the previous one will no longer exist:

```yaml
jobs:
  upload:
    runs-on: ubuntu-latest
    steps:
      - name: Create a file
        run: echo "hello world" > my-file.txt
      - name: Upload Artifact
        uses: actions/upload-artifact@v7
        with:
          name: my-artifact # NOTE: same artifact name
          path: my-file.txt
  upload-again:
    needs: upload
    runs-on: ubuntu-latest
    steps:
      - name: Create a different file
        run: echo "goodbye world" > my-file.txt
      - name: Upload Artifact
        uses: actions/upload-artifact@v7
        with:
          name: my-artifact # NOTE: same artifact name
          path: my-file.txt
          overwrite: true
```

### Uploading Hidden Files

By default, hidden files are ignored by this action to avoid unintentionally uploading sensitive information.

If you need to upload hidden files, you can use the `include-hidden-files` input.
Any files that contain sensitive information that should not be in the uploaded artifact can be excluded
using the `path`:

```yaml
- uses: actions/upload-artifact@v7
  with:
    name: my-artifact
    include-hidden-files: true
    path: |
      path/output/
      !path/output/.production.env
```

Hidden files are defined as any file beginning with `.` or files within folders beginning with `.`.
On Windows, files and directories with the hidden attribute are not considered hidden files unless
they have the `.` prefix.

## Limitations

### Number of Artifacts

Within an individual job, there is a limit of 500 artifacts that can be created for that job.

You may also be limited by Artifacts if you have exceeded your shared storage quota. Storage is calculated every 6-12 hours. See [the documentation](https://docs.github.com/en/billing/managing-billing-for-github-actions/about-billing-for-github-actions#calculating-minute-and-storage-spending) for more info.

### Permission Loss

File permissions are not maintained during zipped artifact upload. All directories will have `755` and all files will have `644`. For example, if you make a file executable using `chmod` and then upload that file with `archive: true`, post-download the file is no longer guaranteed to be set as an executable.

If you must preserve permissions, you can `tar` all of your files together before artifact upload and upload that file directly with `archive: false`. Post download, the `tar` file will maintain file permissions and case sensitivity.

```yaml
- name: 'Tar files'
  run: tar -cvf my_files.tar /path/to/my/directory

- name: 'Upload Artifact'
  uses: actions/upload-artifact@v7
  with:
    path: my_files.tar
    archive: false
```

## Where does the upload go?

At the bottom of the workflow summary page, there is a dedicated section for artifacts. Here's a screenshot of something you might see:




There is a trashcan icon that can be used to delete the artifact. This icon will only appear for users who have write permissions to the repository.

The size of the artifact is denoted in bytes. The displayed artifact size denotes the size of the zip that `upload-artifact` creates during upload. The Digest column will display the SHA256 digest of the artifact being uploaded.

---

## File: docs/MIGRATION.md

# Migration

- [Migration](#migration)
  - [Multiple uploads to the same named Artifact](#multiple-uploads-to-the-same-named-artifact)
  - [Overwriting an Artifact](#overwriting-an-artifact)
  - [Merging multiple artifacts](#merging-multiple-artifacts)
  - [Hidden files](#hidden-files)

Several behavioral differences exist between Artifact actions `v3` and below vs `v4`. This document outlines common scenarios in `v3`, and how they would be handled in `v4`.

## Multiple uploads to the same named Artifact

In `v3`, Artifacts are _mutable_ so it's possible to write workflow scenarios where multiple jobs upload to the same Artifact like so:

```yaml
jobs:
  upload:
    strategy:
      matrix:
        runs-on: [ubuntu-latest, macos-latest, windows-latest]
    runs-on: ${{ matrix.runs-on }}
    steps:
      - name: Create a File
        run: echo "hello from ${{ matrix.runs-on }}" > file-${{ matrix.runs-on }}.txt
      - name: Upload Artifact
        uses: actions/upload-artifact@v3
        with:
          name: my-artifact # NOTE: same artifact name
          path: file-${{ matrix.runs-on }}.txt
  download:
    needs: upload
    runs-on: ubuntu-latest
    steps:
      - name: Download All Artifacts
        uses: actions/download-artifact@v3
        with:
          name: my-artifact
          path: my-artifact
      - run: ls -R my-artifact
```

This results in a directory like so:

```
my-artifact/
  file-macos-latest.txt
  file-ubuntu-latest.txt
  file-windows-latest.txt
```

In v4, Artifacts are immutable (unless deleted). So you must change each of the uploaded Artifacts to have a different name and filter the downloads by name to achieve the same effect:

```diff
jobs:
  upload:
    strategy:
      matrix:
        runs-on: [ubuntu-latest, macos-latest, windows-latest]
    runs-on: ${{ matrix.runs-on }}
    steps:
    - name: Create a File
      run: echo "hello from ${{ matrix.runs-on }}" > file-${{ matrix.runs-on }}.txt
    - name: Upload Artifact
-     uses: actions/upload-artifact@v3
+     uses: actions/upload-artifact@v4
      with:
-       name: my-artifact
+       name: my-artifact-${{ matrix.runs-on }}
        path: file-${{ matrix.runs-on }}.txt
  download:
    needs: upload
    runs-on: ubuntu-latest
    steps:
    - name: Download All Artifacts
-     uses: actions/download-artifact@v3
+     uses: actions/download-artifact@v4
      with:
-       name: my-artifact
        path: my-artifact
+       pattern: my-artifact-*
+       merge-multiple: true
    - run: ls -R my-artifact
```

In `v4`, the new `pattern:` input will filter the downloaded Artifacts to match the name specified. The new `merge-multiple:` input will support downloading multiple Artifacts to the same directory. If the files within the Artifacts have the same name, the last writer wins.

## Overwriting an Artifact

In `v3`, the contents of an Artifact were mutable so something like the following was possible:

```yaml
jobs:
  upload:
    runs-on: ubuntu-latest
    steps:
      - name: Create a file
        run: echo "hello world" > my-file.txt
      - name: Upload Artifact
        uses: actions/upload-artifact@v3
        with:
          name: my-artifact # NOTE: same artifact name
          path: my-file.txt
  upload-again:
    needs: upload
    runs-on: ubuntu-latest
    steps:
      - name: Create a different file
        run: echo "goodbye world" > my-file.txt
      - name: Upload Artifact
        uses: actions/upload-artifact@v3
        with:
          name: my-artifact # NOTE: same artifact name
          path: my-file.txt
```

The resulting `my-file.txt` in `my-artifact` will have "goodbye world" as the content.

In `v4`, Artifacts are immutable unless deleted. To achieve this same behavior, you can use `overwrite: true` to delete the Artifact before a new one is created:

```diff
jobs:
  upload:
    runs-on: ubuntu-latest
    steps:
      - name: Create a file
        run: echo "hello world" > my-file.txt
      - name: Upload Artifact
-       uses: actions/upload-artifact@v3
+       uses: actions/upload-artifact@v4
        with:
          name: my-artifact # NOTE: same artifact name
          path: my-file.txt
  upload-again:
    needs: upload
    runs-on: ubuntu-latest
    steps:
      - name: Create a different file
        run: echo "goodbye world" > my-file.txt
      - name: Upload Artifact
-       uses: actions/upload-artifact@v3
+       uses: actions/upload-artifact@v4
        with:
          name: my-artifact # NOTE: same artifact name
          path: my-file.txt
+         overwrite: true
```

Note that this will create an _entirely_ new Artifact, with a different ID from the previous.

## Merging multiple artifacts

In `v3`, multiple uploads from multiple jobs could be done to the same Artifact. This would result in a single archive, which could be useful for sending to upstream systems outside of Actions via API or UI downloads.

```yaml
jobs:
  upload:
    strategy:
      matrix:
        runs-on: [ubuntu-latest, macos-latest, windows-latest]
    runs-on: ${{ matrix.runs-on }}
    steps:
      - name: Create a File
        run: echo "hello from ${{ matrix.runs-on }}" > file-${{ matrix.runs-on }}.txt
      - name: Upload Artifact
        uses: actions/upload-artifact@v3
        with:
          name: all-my-files # NOTE: same artifact name
          path: file-${{ matrix.runs-on }}.txt
```

The single `all-my-files` artifact would contain the following:

```
.
  ∟ file-ubuntu-latest.txt
  ∟ file-macos-latest.txt
  ∟ file-windows-latest.txt
```

To achieve the same in `v4` you can change it like so:

```diff
jobs:
  upload:
    strategy:
      matrix:
        runs-on: [ubuntu-latest, macos-latest, windows-latest]
    runs-on: ${{ matrix.runs-on }}
    steps:
      - name: Create a File
        run: echo "hello from ${{ matrix.runs-on }}" > file-${{ matrix.runs-on }}.txt
      - name: Upload Artifact
-       uses: actions/upload-artifact@v3
+       uses: actions/upload-artifact@v4
        with:
-         name: all-my-files
+         name: my-artifact-${{ matrix.runs-on }}
          path: file-${{ matrix.runs-on }}.txt
+  merge:
+    runs-on: ubuntu-latest
+    needs: upload
+    steps:
+      - name: Merge Artifacts
+        uses: actions/upload-artifact/merge@v4
+        with:
+          name: all-my-files
+          pattern: my-artifact-*
```

Note that this will download all artifacts to a temporary directory and reupload them as a single artifact. For more information on inputs and other use cases for `actions/upload-artifact/merge@v4`, see [the action documentation](../merge/README.md).

## Hidden Files

By default, hidden files are ignored by this action to avoid unintentionally uploading sensitive
information.

In versions of this action before v4.4.0, these hidden files were included by default.

If you need to upload hidden files, you can use the `include-hidden-files` input.

```yaml
jobs:
  upload:
    runs-on: ubuntu-latest
    steps:
      - name: Create a Hidden File
        run: echo "hello from a hidden file" > .hidden-file.txt
      - name: Upload Artifact
        uses: actions/upload-artifact@v3
        with:
          path: .hidden-file.txt
```


```diff
jobs:
  upload:
    runs-on: ubuntu-latest
    steps:
      - name: Create a Hidden File
        run: echo "hello from a hidden file" > .hidden-file.txt
      - name: Upload Artifact
-       uses: actions/upload-artifact@v3
+       uses: actions/upload-artifact@v4
        with:
          path: .hidden-file.txt
+         include-hidden-files: true
```

---

## File: merge/README.md

# `@actions/upload-artifact/merge`

Merge multiple [Actions Artifacts](https://docs.github.com/en/actions/using-workflows/storing-workflow-data-as-artifacts) in Workflow Runs. Internally powered by [@actions/artifact](https://github.com/actions/toolkit/tree/main/packages/artifact) package.

- [`@actions/upload-artifact/merge`](#actionsupload-artifactmerge)
  - [Usage](#usage)
    - [Inputs](#inputs)
    - [Outputs](#outputs)
  - [Examples](#examples)
    - [Combining all artifacts in a workflow run](#combining-all-artifacts-in-a-workflow-run)
    - [Prefix directories in merged artifact](#prefix-directories-in-merged-artifact)
    - [Deleting artifacts after merge](#deleting-artifacts-after-merge)
    - [Retention and Compression Level](#retention-and-compression-level)

## Usage

> [!IMPORTANT]
> upload-artifact/merge@v4+ is not currently supported on GHES.

Note: this actions can only merge artifacts created with actions/upload-artifact@v4+

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.

### Inputs

```yaml
- uses: actions/upload-artifact/merge@v4
  with:
    # The name of the artifact that the artifacts will be merged into
    # Optional. Default is 'merged-artifacts'
    name:

    # A glob pattern matching the artifacts that should be merged.
    # Optional. Default is '*'
    pattern:

    # 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` |
| `artifact-digest` | SHA-256 digest of an Artifact | 0fde654d4c6e659b45783a725dc92f1bfb0baa6c2de64b34e814dc206ff4aaaf |

## Examples

For each of these examples, assume we have a prior job matrix that generates three artifacts: `my-artifact-a`, `my-artifact-b` and `my-artifact-c`.

e.g.

```yaml
jobs:
  upload:
    runs-on: ubuntu-latest

    strategy:
      matrix:
        foo: [a, b, c]

    steps:
      - name: Run a one-line script
        run: echo "hello from job ${{ matrix.foo }}" > file-${{ matrix.foo }}.txt
      - name: Upload
        uses: actions/upload-artifact@v4
        with:
          name: my-artifact-${{ matrix.foo }}
          path: file-${{ matrix.foo }}.txt
```

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:
  # ...  ...
  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:
  # ...  ...
  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:
  # ...  ...
  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:
  # ...  ...
  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:

```yaml
jobs:
  # ...  ...
  merge:
    runs-on: ubuntu-latest
    needs: upload
    steps:
      - name: Merge Artifacts
        uses: actions/upload-artifact/merge@v4
        with:
          retention-days: 1
          compression-level: 9
```