feat: support deleting merged preview branches

.github/workflows/prune_branches.yml

@@ -0,0 +1,31 @@
+name: Prune merged preview branches
+
+on:
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+
+  prune_branches:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      pull-requests: write
+    steps:
+    - name: Checkout current repo
+      uses: actions/checkout@v3
+      with:
+        fetch-depth: 0
+    - name: Run prune_branches script
+      run: |
+        BRANCHES=($(git branch -r | sed 's/^[[:space:]]*origin\///'))
+        if [ ${#BRANCHES[@]} -gt 0 ]; then
+          ./prune_merged_preview_branches.sh "${BRANCHES[@]}"
+        else
+          echo "No branches to prune."
+        fi
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

prune_merged_preview_branches.sh

@@ -0,0 +1,60 @@
+#!/bin/bash
+
+set -e
+
+check_prerequisites() {
+  # Verify if jq is installed and GITHUB_TOKEN is set.
+  which jq &>/dev/null || (echo "Error: jq is required but not installed. You can download and install jq from <https://stedolan.github.io/jq/download/>." && exit 1)
+
+  test -n "$GITHUB_TOKEN" || (echo "Error: GITHUB_TOKEN (repo scope) is required but not set." && exit 1)
+}
+
+# Select appropriate versions of find and sed depending on the operating system.
+FIND=$(which gfind || which find)
+SED=$(which gsed || which sed)
+
+# Get the directory of this script.
+SCRIPT_DIR=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" &>/dev/null && pwd)
+cd "$SCRIPT_DIR"
+
+check_prerequisites
+
+# Check if arguments are passed
+if [ "$#" -eq 0 ]; then
+  BRANCHES=($(git branch --list | sed 's/^[*[:space:]]*//'))
+else
+  BRANCHES=("$@")
+fi
+
+PRUNE_BRANCHES=()
+
+for branch in "${BRANCHES[@]}"
+do
+  echo "$branch"
+  # Trim leading spaces and the '*' symbol
+  branch="${branch#\* }"
+  branch="${branch# }"
+
+  # Check if the branch starts with "preview"
+  if [[ $branch == preview* ]]; then
+    repo_owner=$(echo "$branch" | cut -d'/' -f2)
+    repo_name=$(echo "$branch" | cut -d'/' -f3)
+    pr_number=$(echo "$branch" | cut -d'/' -f4)
+    is_merged=$(curl -fsSL -H "Authorization: token $GITHUB_TOKEN" \
+    "https://api.github.com/repos/$repo_owner/$repo_name/pulls/$pr_number" |
+    jq -r '.merged_at')
+    if [ -z "$is_merged" ] || [ "$is_merged" = "null" ]; then
+      echo "$branch This PR is not merged, skip."
+    else
+      PRUNE_BRANCHES+=("$branch")
+      echo "$branch This PR is merged, continue."
+    fi
+  fi
+done
+
+# Loop through each branch in the array
+for delete_branch in "${PRUNE_BRANCHES[@]}"
+do
+  echo "Deleting branch: $delete_branch"
+  git push origin --delete $delete_branch
+done