| gcp-project-id | The project ID to use for all GCP services. | yes | — |
| gcp-service-account-key | Base64-encoded key file to use to authenticate against Google Cloud Services. | yes | — |
| gcp-cloud-storage-bucket | The Cloud Storage bucket to use to temporarily store the Cloud Build input files.
By default, a bucket with the name `${projectId}_cloudbuild` will be used. The uploaded files will be deleted after the build has finished. You have to create the specified bucket first manually. | no | — |
| gcp-registry-use-gcr | Enables support for former Google Container Registry repositories migrated to Google Artifact Registry. Defaults to false. | no | — |
| gcp-registry-host | The host to use for Google Artifact Registry. Defaults to europe-docker.pkg.dev.
Find all supported values in the GCP documentation (https://cloud.google.com/artifact-registry/docs/repositories/repo-locations). If you want to use a former GCR repository, this value must be set to one of the GCR endpoints (e.g. `eu.gcr.io`). | no | — |
| gcp-registry-repository | **Required unless you use GCR.** The repository to use for Google Artifact Registry.
You have to create the specified repository first manually. If you want to use a former GCR repository, you can omit this value. The `gcp-project-id` will be used instead. If you want to use a repository in another project, you can still use this parameter to override the project ID default value. | no | — |
| image-name | The name of the image to build. | yes | — |
| image-sources | The sources to use to build the image.
You can include any source files that are within your GitHub workspace, such as build artifacts or Dockerfiles. The option also supports globstar wildcards such as `?`, `*`, `**`, or `[...]`. Read https://github.com/actions/toolkit/tree/master/packages/glob for more details. | yes | — |
| image-tag-format | The format to tag the built image with, if the build was caused by a commit. Builds caused by a tag are always labelled with that tag. The format string can contain the following list of parameters. All other parts of the string are treated as constants. Make sure you only use characters allowed in a docker tag. Defaults to "$BRANCH-$SHA-$YYYY.$MM.$DD-$HH.$mm.$SS", for example "main-4e83ab-2025.01.22-09.08.12". Time is based on the server timezone. $BRANCH The branch name, normalized. $SHA The 7-digit SHA of the commit $YYYY The year in 4-digit format $MM The month in 2-digit format $DD The day in 2-digit format $HH The hour in 2-digit format (24h) $mm The minute in 2-digit-format $SS The second in 2-digit-format | no | — |
| image-tag-latest | Whether the built image will be tagged with latest. Defaults to false. | no | — |
| image-tag-branch-latest | Whether the built image will be tagged with ${branchName}-latest. Defaults to false. | no | — |
| image-tag-additional-tags | A comma-separated list of additional tags to use for the built image. Defaults to false. | no | — |