From 925ec0c61f284a1e55981c68953908257ce880ce Mon Sep 17 00:00:00 2001
From: aidenvaines-bjss <aiden.vaines@bjss.com>
Date: Tue, 10 Sep 2024 16:19:27 +0100
Subject: [PATCH] CCM-6405 Adding github workflow to sync template repo

---
 .../scheduled-repository-template-sync.yaml   |  54 +++++++++
 .../config/.repository-template-sync-ignore   |  18 +++
 scripts/githooks/sync-template-repo.sh        | 110 ++++++++++++++++++
 3 files changed, 182 insertions(+)
 create mode 100644 .github/workflows/scheduled-repository-template-sync.yaml
 create mode 100644 scripts/config/.repository-template-sync-ignore
 create mode 100755 scripts/githooks/sync-template-repo.sh

diff --git a/.github/workflows/scheduled-repository-template-sync.yaml b/.github/workflows/scheduled-repository-template-sync.yaml
new file mode 100644
index 0000000..a227476
--- /dev/null
+++ b/.github/workflows/scheduled-repository-template-sync.yaml
@@ -0,0 +1,54 @@
+name: Repository Template Sync
+
+on:
+  schedule:
+    - cron: '0 0 1 * *'
+  workflow_dispatch:
+
+permissions:
+  contents: write
+  pull-requests: write
+  checks: read
+
+jobs:
+  update-external-repo:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Check out the repository
+      uses: actions/checkout@v4
+
+    - name: Check out external repository
+      uses: actions/checkout@v4
+      with:
+        repository: NHSDigital/nhs-notify-repository-template
+        path: nhs-notify-repository-template
+        token: ${{ github.token }}
+
+    - name: Run syncronisation script
+      run: |
+        ./scripts/githooks/sync-template-repo.sh
+
+    - name: Create Pull Request
+      if: ${{ !env.ACT }}
+      uses: peter-evans/create-pull-request@v7.0.1
+      with:
+        token: ${{ secrets.GITHUB_TOKEN }}
+        commit-message: Drift from template
+        branch: scheduledTemplateRepositorySync
+        delete-branch: true
+        title: '[Template Sync] Drift from template-repository remediation'
+        body: |
+          # Resultant drift from repository template
+
+          ## Who should respond to this PR?
+          The team which owns the responsibility for this component repository. You may want to consult other contributors.
+
+          ## How to progress this PR
+          The repositories guardians should review the contents of the PR and decide how to proceed, you may wish to back-out certain changes or accept them from the upstream `nhsdigital/nhs-notify-repository-template` repository.
+
+          If there are changes you do not wish to see again, it is recommended you add exclusions to `scripts/config/.repository-template-sync-ignore`.
+        labels: |
+          template
+          automation
+        draft: false
diff --git a/scripts/config/.repository-template-sync-ignore b/scripts/config/.repository-template-sync-ignore
new file mode 100644
index 0000000..7564f3e
--- /dev/null
+++ b/scripts/config/.repository-template-sync-ignore
@@ -0,0 +1,18 @@
+# Files and folders to ignore when syncing nhs-notify-repository-template back in to this repository
+scripts/config/.repository-template-sync-ignore
+.github/workflows/
+nhs-notify-repository-template/
+
+# Files and Folders in this repository to ignore
+.vscode/
+CHANGELOG.md
+project.code-workspace
+README.md
+VERSION
+
+# Files and Folders in the template repository to disregard
+.devcontainer/
+.github/workflows/cicd-*.yaml
+*/examples/
+docs/
+infrastructure/terraform/components/
diff --git a/scripts/githooks/sync-template-repo.sh b/scripts/githooks/sync-template-repo.sh
new file mode 100755
index 0000000..060aaa4
--- /dev/null
+++ b/scripts/githooks/sync-template-repo.sh
@@ -0,0 +1,110 @@
+#!/bin/bash
+
+set -euo pipefail
+
+# Script to synchronise the nhs-notify-template-repository with this repository
+#
+# Usage:
+#   $ [options] ./check-terraform-format.sh
+#
+# Options:
+#   new_only=true      # Only identify new files from the template-repository
+#   changes_only=true  # Only identify files which have drifted from the template-repository
+
+# ==============================================================================
+
+# Command line prameters
+new_only=${new_only:-false}
+changes_only=${changes_only:-false}
+
+# Set variables
+TEMPLATE_REPO_DIR="nhs-notify-repository-template"
+IGNORE_FILE="scripts/config/.repository-template-sync-ignore"
+
+# Check if the template directory exists
+if [ ! -d "${TEMPLATE_REPO_DIR}" ]; then
+  echo "Template directory ${TEMPLATE_REPO_DIR} not found!"
+  exit 1
+fi
+
+# Check if the .template-ignore file exists, create an empty one if not
+if [ ! -f "${IGNORE_FILE}" ]; then
+  echo "# Files and folders to ignore when syncing ${TEMPLATE_REPO_DIR} back in to this repository" > ${IGNORE_FILE}
+  echo "# Files and Folders in this repository to ignore" >> ${IGNORE_FILE}
+  echo "# Files and Folders in the template repository to disregard" >> ${IGNORE_FILE}
+fi
+
+# Read the .template-ignore file into an array
+while IFS= read -r line || [ -n "$line" ]; do
+  IGNORED_PATHS+=("$line")
+done < "$IGNORE_FILE"
+
+# Check if a file is ignored.
+is_ignored() {
+  local file=${1}
+
+  # Ignore .git directories and files
+  if [[ "$file" == *.git/* ]]; then
+    return 0
+  fi
+
+  for ignored in "${IGNORED_PATHS[@]}"; do
+    if [[ -n "$ignored" && "$file" =~ $ignored ]]; then
+      return 0
+    fi
+  done
+  return 1
+}
+
+# Navigate to the template directory
+cd "${TEMPLATE_REPO_DIR}" || exit
+FILES_ADDED=()
+FILES_WITH_CHANGES=()
+
+# Loop through all files in the template directory
+while IFS= read -r -d '' file; do
+  relative_path="${file#./}"  # Remove leading './'
+
+  # Check if the file is ignored
+  if is_ignored "$relative_path"; then
+    echo "Ignoring $relative_path"
+    continue
+  fi
+
+  target_path="../$relative_path"
+  mkdir -p "$(dirname "$target_path")"
+
+  # Copy the file to the root directory if it doesn't exist or is different
+  if [ ! -f "$target_path" ] && [ "$changes_only" == false ]; then
+    echo "Copying $relative_path to the repository"
+    FILES_ADDED+=("${relative_path}")
+    cp "$file" "$target_path"
+
+  else
+    # If the file exists, check if it's different
+    if [ "$new_only" == false ]; then
+      if ! diff -q "$file" "$target_path" > /dev/null 2>&1; then
+        echo "Merging changes from $relative_path"
+        FILES_WITH_CHANGES+=("${relative_path}")
+        cp "$file" "$target_path"
+      fi
+    fi
+  fi
+done < <(find . -type f -print0)
+
+echo "${#FILES_ADDED[@]}" files added, "${#FILES_WITH_CHANGES[@]}" files with changes detected.
+
+echo ------------------------------------------
+
+if [ "$changes_only" == false ]; then
+  echo ------------------------------------------
+  echo "New files added:"
+  printf ' - %s\n' "${FILES_ADDED[@]}"
+fi
+
+
+if [ "$new_only" == false ]; then
+  echo ------------------------------------------
+  echo "Changed files:"
+  printf ' - %s\n' "${FILES_WITH_CHANGES[@]}"
+fi