updater-pubspec

Updates the version: field in pubspec.yaml for Dart and Flutter projects.

This plugin is distributed as the standalone Go binary semrel-plugin-updater-pubspec. Semrel executes the binary as a subprocess, provides plugin configuration through SEMREL_PLUGIN_* environment variables, provides release context through SEMREL_* environment variables, reads standard output, and treats exit code 0 as success and any non-zero exit code as failure. Install the binary in ~/.semrel/plugins/ or anywhere on your $PATH.

Installation

Binary

go install github.com/SemRels/updater-pubspec/cmd/plugin@latest

Docker

Pre-built, multi-platform images (linux/amd64, linux/arm64) are published to the GitHub Container Registry on every release:

docker pull ghcr.io/semrels/updater-pubspec:latest

Images are signed with cosign and include a full SBOM attestation. Verify the signature:

cosign verify ghcr.io/semrels/updater-pubspec:latest \
  --certificate-identity-regexp 'https://github.com/SemRels/updater-pubspec/.github/workflows/release.yml.*' \
  --certificate-oidc-issuer https://token.actions.githubusercontent.com

Configuration (.semrel.yaml)

plugins:
  - name: updater-pubspec
    path: ~/.semrel/plugins/semrel-plugin-updater-pubspec
    env:
      SEMREL_PLUGIN_PUBSPEC_PATH: "packages/app/pubspec.yaml"
      SEMREL_PLUGIN_PUBSPEC_BUILD_STRATEGY: "increment"

SEMREL_PLUGIN_* variables

Name	Required	Description	Default
SEMREL_PLUGIN_PUBSPEC_PATH	Optional	Path to the pubspec.yaml file to update.	./pubspec.yaml
SEMREL_PLUGIN_PUBSPEC_BUILD_STRATEGY	Optional	Build suffix strategy: none, increment, or release-count.	none
SEMREL_PLUGIN_PUBSPEC_BUILD_NUMBER	Optional	Explicit build number override. When set it always wins and writes SEMREL_VERSION+<number>.	unset

SEMREL_* release context used

Variable	Description
SEMREL_VERSION	Resolved release version for the current run.
SEMREL_NEXT_VERSION	Next version computed by semrel for the release.
SEMREL_DRY_RUN	Whether semrel is running in dry-run mode.
SEMREL_RELEASE_COUNT	Optional release-count input if semrel or the caller provides it.
SEMREL_BUILD_NUMBER	Optional build-number input if CI or semrel provides it.

Build number strategies

The plugin always strips a leading v from SEMREL_VERSION / SEMREL_NEXT_VERSION before writing the semver part.

none (default)

Removes any existing Flutter build suffix and writes only the bare semver.

Before:

version: 1.4.0+42

After SEMREL_VERSION=v1.5.0:

version: 1.5.0

increment

Reads the current top-level version: line, increments the existing +build number, and preserves the rest of the file unchanged. If no build suffix exists, the plugin starts at +1. If the existing suffix is malformed, the plugin logs a warning to stderr and starts fresh at +1.

Before:

version: 1.4.0+42

After SEMREL_VERSION=v1.5.0:

version: 1.5.0+43

release-count

Use this when you want the Flutter build suffix to mirror a monotonically increasing release or CI counter.

Priority order:

1. SEMREL_PLUGIN_PUBSPEC_BUILD_NUMBER
2. SEMREL_RELEASE_COUNT
3. SEMREL_BUILD_NUMBER
4. Fallback to existing build + 1 with a warning if none of the above are set

Semrel's current ecosystem does not appear to expose a dedicated release-count environment variable yet, so callers commonly pass an external counter (for example GITHUB_RUN_NUMBER) through SEMREL_PLUGIN_PUBSPEC_BUILD_NUMBER.

Before:

version: 1.4.0+42

After with SEMREL_VERSION=v1.5.0 and SEMREL_PLUGIN_PUBSPEC_BUILD_NUMBER=108:

version: 1.5.0+108

Dry runs

With SEMREL_DRY_RUN=true, the plugin validates the file, computes the exact new version: line, prints it, and leaves pubspec.yaml untouched.

Example behavior

The plugin performs a surgical line-based replacement of the top-level version: key so comments, indentation, dependency blocks, and the rest of the YAML file remain untouched.

Local validation

go test ./...
go vet ./...
go build ./...

License

Apache-2.0