7.9 KiB
Migration
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:
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:
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:
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:
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.
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:
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.
Working with Immutable Artifacts
In v4, artifacts are immutable by default and each artifact gets a unique ID when uploaded. When an artifact with the same name is uploaded again (with or without overwrite: true), it gets a new artifact ID.
To take advantage of this immutability for security purposes (to avoid potential TOCTOU issues where an artifact might be replaced between upload and download), the new artifact-ids input allows you to download artifacts by their specific ID rather than by name:
jobs:
upload:
runs-on: ubuntu-latest
steps:
- name: Create a file
run: echo "hello world" > my-file.txt
- name: Upload Artifact
id: upload
uses: actions/upload-artifact@v4
with:
name: my-artifact
path: my-file.txt
# The upload step outputs the artifact ID
- name: Print Artifact ID
run: echo "Artifact ID is ${{ steps.upload.outputs.artifact-id }}"
download:
needs: upload
runs-on: ubuntu-latest
steps:
- name: Download Artifact by ID
uses: actions/download-artifact@v4
with:
# Use the artifact ID directly, not the name, to ensure you get exactly the artifact you expect
artifact-ids: ${{ needs.upload.outputs.artifact-id }}
This approach provides stronger guarantees about which artifact version you're downloading compared to using just the artifact name.