chore(release): update branch and tags according to schedule

Using the release info derived from release-schedule.json:

* for each release that is not EOL and for which the cut date is in
  the past, ensure that:
  * a v* branch exists or create it from next
  * a backport/label exists or create it
* for each backport/* labels, archive those that match a release that
  is EOL

.forgejo/forgejo-release-sync/action.yml

@@ -0,0 +1,111 @@
+# Copyright The Forgejo Authors
+# SPDX-License-Identifier: MIT
+
+name: 'Sync with Forgejo releases'
+author: 'Forgejo authors'
+
+inputs:
+  forgejo:
+    description: 'URL of the Forgejo instance'
+    required: true
+  repository:
+    description: 'Repository of the Forgejo documentation'
+    required: true
+  token:
+    description: 'Token with repository and issues write permissions to the repository'
+    required: true
+  api:
+    description: 'curl command to the API'
+    required: true
+  today:
+    description: 'todays date as YYYY-MM-DD'
+  dry-run:
+    description: 'set to echo to do display commands instead of carrying them out'
+  verbose:
+    description: 'Increase the verbosity level'
+    default: 'false'
+
+outputs:
+  releases:
+    value: '${{ steps.releases.outputs.value }}'
+  branches-add:
+    value: '${{ steps.branches-add.outputs.value }}'
+  labels-archive:
+    value: '${{ steps.labels-archive.outputs.value }}'
+  labels-add:
+    value: '${{ steps.labels-add.outputs.value }}'
+
+runs:
+  using: 'composite'
+  steps:
+    - name: apt install jq
+      run: |
+        ${{ inputs.verbose }} && set -x
+        if ! which jq ; then
+          export DEBIAN_FRONTEND=noninteractive
+          apt-get update -qq
+          apt-get -q install -y -qq jq
+        fi
+
+    - name: forgejo release schedule
+      run: |
+        ${{ inputs.verbose }} && set -x
+        curl --fail -sS -o release-schedule.json https://codeberg.org/forgejo/docs/raw/branch/next/release-schedule.json
+        cat release-schedule.json
+
+    - name: current forgejo releases
+      id: releases
+      run: |
+        ${{ inputs.verbose }} && set -x
+        today=${{ inputs.today }}
+        if test -z "$today"; then
+          today=$(date +%F)
+        fi
+        jq --raw-output '.[] | select(.eol > "'$today'" and .cut <= "'$today'") | "\(.major).\(.minor)"' < release-schedule.json | sort | tee releases-current.txt
+        echo value=$(cat releases-current.txt) >> $GITHUB_OUTPUT
+
+    - name: get existing stable branches
+      run: |
+        ${{ inputs.verbose }} && set -x
+        ${{ inputs.api }}/branches | jq --raw-output '.[] | select(.name | startswith("v")) | .name' | sed -e 's/^v//' | sort | tee docs-branches.txt
+
+    - name: add missing stable branches
+      id: branches-add
+      run: |
+        ${{ inputs.verbose }} && set -x
+        > value
+        comm -23 releases-current.txt docs-branches.txt | while read version ; do
+           ${{ inputs.dry-run }} ${{ inputs.api }}/branches -X POST --data '{"new_branch_name":"v'$version'","old_branch_name":"next"}'
+           echo $version >> value
+        done
+        echo value=$(cat value) >> $GITHUB_OUTPUT
+
+    - name: get existing backport labels
+      run: |
+        ${{ inputs.verbose }} && set -x
+        ${{ inputs.api }}/labels | jq --raw-output '.[] | select((.is_archived == false) and (.name | startswith("backport/"))) | "\(.name) \(.id)"' | sed -e 's|^backport/v||' | sort | tee docs-backport-labels.txt
+
+    - name: archive old backport labels
+      id: labels-archive
+      run: |
+        ${{ inputs.verbose }} && set -x
+        > value
+        cat docs-backport-labels.txt | while read version id ; do
+           if grep --quiet "^$version$" releases-current.txt ; then
+             continue
+           fi
+           echo $version >> value
+           ${{ inputs.dry-run }} ${{ inputs.api }}/labels/$id -X PATCH --data '{"is_archived": true}'
+        done
+        echo value=$(cat value) >> $GITHUB_OUTPUT
+
+    - name: add missing backport labels
+      id: labels-add
+      run: |
+        ${{ inputs.verbose }} && set -x
+        > value
+        cut -f1 -d' ' docs-backport-labels.txt | comm -23 releases-current.txt - | while read version ; do
+           ${{ inputs.dry-run }} ${{ inputs.api }}/labels -X POST --data '{"name":"backport/v'$version'","description":"Automated backport to the v'$version'docs","color":"#bfe5bf"}'
+           echo $version >> value
+        done
+        echo value=$(cat value) >> $GITHUB_OUTPUT

.forgejo/workflows/forgejo-release-sync-test.yml

@@ -0,0 +1,120 @@
+# Copyright The Forgejo Authors
+# SPDX-License-Identifier: MIT
+
+name: forgejo-release
+
+#
+# Changing this workflow must not be from a fork otherwise the secret
+# won't be available to write in the playground:
+#
+# * push to a branch of this repository
+# * open a pull request
+#
+
+on:
+  pull_request:
+    paths:
+      - .forgejo/forgejo-release-sync/**
+      - .forgejo/workflows/forgejo-release-sync*.yml
+
+env:
+  FORGEJO: https://codeberg.org
+  REPOSITORY: forgejo-contrib/docs-playground
+  API: "curl --fail -sS -H 'Content-Type: application/json' -H 'Authorization: Bearer ${{ secrets.DOCS_PLAYGROUND_TOKEN }}' ${{ env.FORGEJO }}/api/v1/repos/${{ env.REPOSITORY }}"
+
+jobs:
+  sync-test:
+    runs-on: docker
+    container:
+      image: 'code.forgejo.org/oci/node:20-bookworm'
+    steps:
+      - uses: https://code.forgejo.org/actions/checkout@v4
+
+      - name: apt install jq
+        run: |
+          export DEBIAN_FRONTEND=noninteractive
+          apt-get update -qq
+          apt-get -q install -y -qq jq
+
+      - name: setup fixture
+        run: |
+          set -x
+          ${{ env.API }}/branches | jq --raw-output '.[] | select(.protected == false) | .name' | while read branch ; do
+            ${{ env.API }}/branches/$branch -X DELETE
+          done
+          ${{ env.API }}/labels | jq --raw-output '.[] | .id' | while read label ; do
+            ${{ env.API }}/labels/$label -X DELETE
+          done
+
+      - name: dry run sync
+        id: sync-dry-run
+        uses: ./.forgejo/forgejo-release-sync
+        with:
+          forgejo: ${{ env.FORGEJO }}
+          repository: ${{ env.REPOSITORY }}
+          token: ${{ secrets.DOCS_PLAYGROUND_TOKEN }}
+          api: ${{ env.API }}
+          dry-run: echo
+          verbose: true
+
+      - name: assert dry run sync
+        run: |
+          set -x
+          test "${{ steps.sync-dry-run.outputs.releases }}"
+
+      # 7.0 and 9.0 are stable
+      - name: 2024-11-22 sync
+        id: sync-2024-11-22
+        uses: ./.forgejo/forgejo-release-sync
+        with:
+          forgejo: ${{ env.FORGEJO }}
+          repository: ${{ env.REPOSITORY }}
+          token: ${{ secrets.DOCS_PLAYGROUND_TOKEN }}
+          api: ${{ env.API }}
+          today: 2024-11-22
+          verbose: true
+
+      - name: 2024-11-22 assert
+        run: |
+          set -x
+          test "${{ steps.sync-2024-11-22.outputs.branches-add }}" = "7.0 9.0"
+          test "${{ steps.sync-2024-11-22.outputs.labels-archive }}" = ""
+          test "${{ steps.sync-2024-11-22.outputs.labels-add }}" = "7.0 9.0"
+
+      # 7.0 and 9.0 are stable and the 10.0 branch is cut
+      - name: 2024-12-31 sync
+        id: sync-2024-12-31
+        uses: ./.forgejo/forgejo-release-sync
+        with:
+          forgejo: ${{ env.FORGEJO }}
+          repository: ${{ env.REPOSITORY }}
+          token: ${{ secrets.DOCS_PLAYGROUND_TOKEN }}
+          api: ${{ env.API }}
+          today: 2024-12-31
+          verbose: true
+
+      # 7.0 and 10.0 are stable and 9.0 is EOL
+      - name: 2024-12-31 assert
+        run: |
+          set -x
+          test "${{ steps.sync-2024-12-31.outputs.branches-add }}" = "10.0"
+          test "${{ steps.sync-2024-12-31.outputs.labels-archive }}" = ""
+          test "${{ steps.sync-2024-12-31.outputs.labels-add }}" = "10.0"
+
+      - name: 2025-01-28 sync
+        id: sync-2025-01-28
+        uses: ./.forgejo/forgejo-release-sync
+        with:
+          forgejo: ${{ env.FORGEJO }}
+          repository: ${{ env.REPOSITORY }}
+          token: ${{ secrets.DOCS_PLAYGROUND_TOKEN }}
+          api: ${{ env.API }}
+          today: 2025-01-28
+          verbose: true
+
+      - name: 2025-01-28 assert
+        run: |
+          set -x
+          test "${{ steps.sync-2025-01-28.outputs.branches-add }}" = ""
+          test "${{ steps.sync-2025-01-28.outputs.labels-archive }}" = "9.0"
+          test "${{ steps.sync-2025-01-28.outputs.labels-add }}" = ""

.forgejo/workflows/forgejo-release-sync.yml

@@ -0,0 +1,37 @@
+# Copyright The Forgejo Authors
+# SPDX-License-Identifier: MIT
+
+#
+# Keep the docs repository up to date based on the Forgejo schedule release
+# found at https://codeberg.org/forgejo/docs/raw/branch/next/release-schedule.json
+#
+# * cut documentation branches at the same time as the Forgejo main repository
+# * create and archive the backport labels
+# * ...
+#
+
+name: forgejo-release
+
+on:
+  #  schedule:
+  #    - cron: '15 5 * * *'
+  workflow_dispatch:
+
+env:
+  FORGEJO: https://codeberg.org
+  REPOSITORY: forgejo/docs
+  API: "curl --fail -sS -H 'Content-Type: application/json' -H 'Authorization: Bearer ${{ secrets.WEBSITETOKEN }}' ${{ env.FORGEJO }}/api/v1/repos/${{ env.REPOSITORY }}"
+
+jobs:
+  sync:
+    if: secrets.WEBSITETOKEN != ''
+    runs-on: docker
+    container:
+      image: 'code.forgejo.org/oci/node:20-bookworm'
+    steps:
+      - uses: ./.forgejo/forgejo-release-sync
+        with:
+          forgejo: ${{ env.FORGEJO }}
+          repository: ${{ env.REPOSITORY }}
+          api: ${{ env.API }}
+          dry-run: ${{ vars.FORGEJO_RELEASE_DRY_RUN }}