tekton: automate releases with Pipelines-as-Code

.github/workflows/patch-release.yaml

@@ -0,0 +1,177 @@
+name: Patch Release
+
+"on":
+  workflow_dispatch:
+    inputs:
+      branch:
+        description: "Release branch (e.g. release-v0.26.x)"
+        required: true
+        type: string
+      version:
+        description: "Version to release (e.g. v0.26.4)"
+        required: true
+        type: string
+      release_as_latest:
+        description: "Publish as latest release"
+        required: false
+        type: boolean
+        default: true
+  schedule:
+    # Weekly on Thursday at 10:00 UTC
+    - cron: "0 10 * * 4"
+
+env:
+  PAC_CONTROLLER_URL: "https://pac.infra.tekton.dev"
+  PAC_REPOSITORY_NAME: "tektoncd-chains"
+  # Ignore release branches older than this (major.minor)
+  MIN_RELEASE_VERSION: "0.20"
+
+jobs:
+  scan-release-branches:
+    name: Scan for unreleased commits
+    if: github.event_name == 'schedule' && github.repository_owner == 'tektoncd'
+    runs-on: ubuntu-latest
+    outputs:
+      matrix: ${{ steps.scan.outputs.matrix }}
+      has_releases: ${{ steps.scan.outputs.has_releases }}
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          fetch-depth: 0
+
+      - name: Scan release branches for new commits
+        id: scan
+        run: |
+          # Determine which release branch is the latest (highest version)
+          latest_branch=""
+          latest_major=0
+          latest_minor=0
+          for ref in $(git branch -r --list 'origin/release-v*'); do
+            branch="${ref#origin/}"
+            if [[ "$branch" =~ release-v([0-9]+)\.([0-9]+)\.x ]]; then
+              major="${BASH_REMATCH[1]}"
+              minor="${BASH_REMATCH[2]}"
+              if [ "$major" -gt "$latest_major" ] || { [ "$major" -eq "$latest_major" ] && [ "$minor" -gt "$latest_minor" ]; }; then
+                latest_major=$major
+                latest_minor=$minor
+                latest_branch=$branch
+              fi
+            fi
+          done
+          echo "::notice::Latest release branch: ${latest_branch}"
+
+          MIN_MAJOR="${MIN_RELEASE_VERSION%%.*}"
+          MIN_MINOR="${MIN_RELEASE_VERSION##*.}"
+
+          releases=()
+          for ref in $(git branch -r --list 'origin/release-v*'); do
+            branch="${ref#origin/}"
+
+            # Skip branches older than MIN_RELEASE_VERSION
+            if [[ "$branch" =~ release-v([0-9]+)\.([0-9]+)\.x ]]; then
+              major="${BASH_REMATCH[1]}"
+              minor="${BASH_REMATCH[2]}"
+              if [ "$major" -lt "$MIN_MAJOR" ] || { [ "$major" -eq "$MIN_MAJOR" ] && [ "$minor" -lt "$MIN_MINOR" ]; }; then
+                echo "::notice::Branch ${branch} is older than v${MIN_RELEASE_VERSION} — skipping"
+                continue
+              fi
+            fi
+
+            # Find the latest tag on this branch
+            last_tag=$(git describe --tags --abbrev=0 --match 'v*' "$ref" 2>/dev/null || echo "")
+            if [ -z "$last_tag" ]; then
+              echo "::notice::Branch ${branch} has no tags — skipping (initial release handled by branch creation)"
+              continue
+            fi
+
+            # Count commits since last tag
+            new_commits=$(git rev-list "${last_tag}..${ref}" --count)
+            if [ "$new_commits" -eq 0 ]; then
+              echo "::notice::Branch ${branch} has no new commits since ${last_tag}"
+              continue
+            fi
+
+            # Calculate next patch version: v0.26.3 → v0.26.4
+            next_version=$(echo "$last_tag" | awk -F. '{printf "%s.%s.%d", $1, $2, $3+1}')
+
+            # Only the latest release branch publishes as latest
+            is_latest="false"
+            if [ "$branch" = "$latest_branch" ]; then
+              is_latest="true"
+            fi
+
+            echo "::notice::Branch ${branch}: ${new_commits} new commits since ${last_tag} → ${next_version} (latest=${is_latest})"
+            releases+=("{\"branch\":\"${branch}\",\"version\":\"${next_version}\",\"release_as_latest\":\"${is_latest}\"}")
+          done
+
+          if [ ${#releases[@]} -eq 0 ]; then
+            echo "matrix=[]" >> "$GITHUB_OUTPUT"
+            echo "has_releases=false" >> "$GITHUB_OUTPUT"
+          else
+            echo "matrix=[$(IFS=,; echo "${releases[*]}")]" >> "$GITHUB_OUTPUT"
+            echo "has_releases=true" >> "$GITHUB_OUTPUT"
+          fi
+
+  trigger-scanned-releases:
+    name: "Trigger ${{ matrix.release.version }} (${{ matrix.release.branch }})"
+    needs: scan-release-branches
+    if: needs.scan-release-branches.outputs.has_releases == 'true'
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        release: ${{ fromJson(needs.scan-release-branches.outputs.matrix) }}
+      max-parallel: 1
+    steps:
+      - name: Trigger PAC incoming webhook
+        env:
+          PAC_INCOMING_SECRET: ${{ secrets.PAC_INCOMING_SECRET }}
+        run: |
+          echo "::notice::Triggering release ${{ matrix.release.version }} on ${{ matrix.release.branch }} (latest=${{ matrix.release.release_as_latest }})"
+          curl -sf -X POST "${PAC_CONTROLLER_URL}/incoming" \
+            -H "Content-Type: application/json" \
+            -d '{
+              "repository": "'"${PAC_REPOSITORY_NAME}"'",
+              "branch": "${{ matrix.release.branch }}",
+              "pipelinerun": "release-patch",
+              "secret": "'"${PAC_INCOMING_SECRET}"'",
+              "params": {
+                "version": "${{ matrix.release.version }}",
+                "release_as_latest": "${{ matrix.release.release_as_latest }}"
+              }
+            }'
+          echo "Release triggered successfully"
+
+  trigger-manual-release:
+    name: "Trigger ${{ inputs.version }} (${{ inputs.branch }})"
+    if: github.event_name == 'workflow_dispatch' && github.repository_owner == 'tektoncd'
+    runs-on: ubuntu-latest
+    steps:
+      - name: Validate inputs
+        run: |
+          if [[ ! "${{ inputs.branch }}" =~ ^release-v[0-9]+\.[0-9]+\.x$ ]]; then
+            echo "::error::Invalid branch format: ${{ inputs.branch }}. Expected: release-vX.Y.x"
+            exit 1
+          fi
+          if [[ ! "${{ inputs.version }}" =~ ^v[0-9]+\.[0-9]+\.[0-9]+$ ]]; then
+            echo "::error::Invalid version format: ${{ inputs.version }}. Expected: vX.Y.Z"
+            exit 1
+          fi
+
+      - name: Trigger PAC incoming webhook
+        env:
+          PAC_INCOMING_SECRET: ${{ secrets.PAC_INCOMING_SECRET }}
+        run: |
+          echo "::notice::Triggering release ${{ inputs.version }} on ${{ inputs.branch }} (latest=${{ inputs.release_as_latest }})"
+          curl -sf -X POST "${PAC_CONTROLLER_URL}/incoming" \
+            -H "Content-Type: application/json" \
+            -d '{
+              "repository": "'"${PAC_REPOSITORY_NAME}"'",
+              "branch": "${{ inputs.branch }}",
+              "pipelinerun": "release-patch",
+              "secret": "'"${PAC_INCOMING_SECRET}"'",
+              "params": {
+                "version": "${{ inputs.version }}",
+                "release_as_latest": "${{ inputs.release_as_latest }}"
+              }
+            }'
+          echo "Release triggered successfully"

.tekton/release-patch.yaml

@@ -0,0 +1,83 @@
+# Copyright 2026 The Tekton Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This PipelineRun is triggered via PAC incoming webhooks for patch
+# releases on existing release branches. It is invoked either manually
+# (via GitHub Actions workflow_dispatch) or on a cron schedule when
+# new commits are detected on a release branch since the last tag.
+#
+# The version and release_as_latest parameters are passed dynamically
+# through the incoming webhook payload.
+apiVersion: tekton.dev/v1
+kind: PipelineRun
+metadata:
+  name: release-patch
+  annotations:
+    pipelinesascode.tekton.dev/on-event: "[incoming]"
+    pipelinesascode.tekton.dev/on-target-branch: "[release-v*]"
+    pipelinesascode.tekton.dev/pipeline: "release/release-pipeline.yaml"
+    pipelinesascode.tekton.dev/max-keep-runs: "5"
+spec:
+  taskRunTemplate:
+    serviceAccountName: release
+  pipelineRef:
+    name: chains-release
+  params:
+    - name: package
+      value: github.com/tektoncd/chains
+    - name: repoName
+      value: chains
+    - name: gitRevision
+      value: "{{ revision }}"
+    - name: imageRegistry
+      value: ghcr.io
+    - name: imageRegistryPath
+      value: tektoncd/chains
+    - name: imageRegistryRegions
+      value: ""
+    - name: imageRegistryUser
+      value: tekton-robot
+    - name: versionTag
+      value: "{{ version }}"
+    - name: releaseBucket
+      value: tekton-releases
+    - name: releaseAsLatest
+      value: "{{ release_as_latest }}"
+    - name: buildPlatforms
+      value: linux/amd64,linux/arm64,linux/s390x,linux/ppc64le
+    - name: publishPlatforms
+      value: linux/amd64,linux/arm64,linux/s390x,linux/ppc64le,windows/amd64
+    - name: koExtraArgs
+      value: "--preserve-import-paths"
+    - name: serviceAccountImagesPath
+      value: credentials
+    - name: runTests
+      value: "true"
+  timeouts:
+    pipeline: 3h0m0s
+  workspaces:
+    - name: workarea
+      volumeClaimTemplate:
+        spec:
+          accessModes:
+            - ReadWriteOnce
+          resources:
+            requests:
+              storage: 1Gi
+    - name: release-secret
+      secret:
+        secretName: oci-release-secret
+    - name: release-images-secret
+      secret:
+        secretName: ghcr-creds

.tekton/release.yaml

@@ -0,0 +1,92 @@
+# Copyright 2026 The Tekton Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This PipelineRun is triggered by Pipelines-as-Code when a release
+# branch (release-v*) is first created. It runs the chains release
+# pipeline defined in release/release-pipeline.yaml.
+#
+# The release pipeline builds, publishes multi-arch images, uploads
+# artifacts to the release bucket, and reports the release URLs.
+apiVersion: tekton.dev/v1
+kind: PipelineRun
+metadata:
+  name: release-pipeline
+  annotations:
+    # Trigger on push events to release branches, but ONLY when the branch
+    # is first created (body.created == true). This means it fires exactly
+    # once per release branch, not on every commit pushed to it.
+    # NOTE: on-cel-expression takes precedence over on-event/on-target-branch,
+    # so the branch filter MUST be included in the CEL expression.
+    pipelinesascode.tekton.dev/on-event: "[push]"
+    pipelinesascode.tekton.dev/on-target-branch: "[refs/heads/release-v*]"
+    pipelinesascode.tekton.dev/on-cel-expression: |
+      event == "push" && has(body.created) && body.created == true &&
+      target_branch.startsWith("release-v")
+    pipelinesascode.tekton.dev/pipeline: "release/release-pipeline.yaml"
+    pipelinesascode.tekton.dev/max-keep-runs: "5"
+spec:
+  taskRunTemplate:
+    serviceAccountName: release
+  pipelineRef:
+    name: chains-release
+  params:
+    - name: package
+      value: github.com/tektoncd/chains
+    - name: repoName
+      value: chains
+    - name: gitRevision
+      value: "{{ revision }}"
+    - name: imageRegistry
+      value: ghcr.io
+    - name: imageRegistryPath
+      value: tektoncd/chains
+    - name: imageRegistryRegions
+      value: ""
+    - name: imageRegistryUser
+      value: tekton-robot
+    # For initial releases, the version is derived from the branch name:
+    # release-v0.26.x → v0.26.0
+    - name: versionTag
+      value: '{{ cel: pac.target_branch.replace("release-", "").replace(".x", ".0") }}'
+    - name: releaseBucket
+      value: tekton-releases
+    - name: releaseAsLatest
+      value: "true"
+    - name: buildPlatforms
+      value: linux/amd64,linux/arm64,linux/s390x,linux/ppc64le
+    - name: publishPlatforms
+      value: linux/amd64,linux/arm64,linux/s390x,linux/ppc64le,windows/amd64
+    - name: koExtraArgs
+      value: "--preserve-import-paths"
+    - name: serviceAccountImagesPath
+      value: credentials
+    - name: runTests
+      value: "true"
+  timeouts:
+    pipeline: 3h0m0s
+  workspaces:
+    - name: workarea
+      volumeClaimTemplate:
+        spec:
+          accessModes:
+            - ReadWriteOnce
+          resources:
+            requests:
+              storage: 1Gi
+    - name: release-secret
+      secret:
+        secretName: oci-release-secret
+    - name: release-images-secret
+      secret:
+        secretName: ghcr-creds