auto-update.yml

name: AUTO-UPDATE

on:
  schedule:
    - cron: '0 2 * * *'
  workflow_dispatch:
  push:
    branches:
      - main

jobs:
  check-and-update:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3

      - name: Fetch latest .NET versions
        run: |
          curl -s https://raw.githubusercontent.com/dotnet/core/main/release-notes/releases-index.json > releases-index.json
          echo "Fetched latest .NET versions"

      - name: Check for updates
        id: check-updates
        run: |
          latest_versions=$(jq -r '
            [.["releases-index"][] 
              | select(.["support-phase"] == "active" and .["release-type"] == "lts")
              | {majorminor: (.["channel-version"] | split(".")[0:2] | join(".")), sdk: .["latest-sdk"], runtime: .["latest-runtime"]}
            ]
            | group_by(.majorminor)
            | map({(.[0].majorminor): {sdk: .[0].sdk, runtime: .[0].runtime}})
            | add
          ' releases-index.json)

          jq -c '.[]' image-matrix.json | while read -r entry; do
            current_net_version=$(echo "$entry" | jq -r '.netVersion')
            current_sdk_version=$(echo "$entry" | jq -r '.sdkVersion')
            current_runtime_version=$(echo "$entry" | jq -r '.runtimeVersion')
            alpine_version=$(echo "$entry" | jq -r '.alpineVersion')

            # Get the latest SDK and runtime for the major.minor version
            latest_sdk_version=$(echo "$latest_versions" | jq -r --arg ver "$current_net_version" '.[$ver].sdk // empty')
            latest_runtime_version=$(echo "$latest_versions" | jq -r --arg ver "$current_net_version" '.[$ver].runtime // empty')

            # Check if updates are needed
            if [[ -n "$latest_sdk_version" && "$latest_sdk_version" != "$current_sdk_version" ]] || [[ -n "$latest_runtime_version" && "$latest_runtime_version" != "$current_runtime_version" ]]; then
              # Verify if the Alpine image exists
              image="mcr.microsoft.com/dotnet/aspnet:${current_net_version}-alpine${alpine_version}"
              if docker pull "$image" &>/dev/null; then
                echo "Update needed for .NET $current_net_version: SDK $current_sdk_version -> $latest_sdk_version, Runtime $current_runtime_version -> $latest_runtime_version"
                echo "$current_net_version:$latest_sdk_version:$latest_runtime_version:$alpine_version" >> updates.txt
              else
                echo "No Alpine image available for .NET $major_version with Alpine $alpine_version. Skipping update."
              fi
            fi
          done

          # Check if updates.txt exists and is not empty
          if [[ -s updates.txt ]]; then
            echo "update_needed=true" >> $GITHUB_ENV
          else
            echo "update_needed=false" >> $GITHUB_ENV
          fi

      - name: Update files
        if: env.update_needed == 'true'
        run: |
          # Update image-matrix.json
          while IFS=: read -r net_version sdk_version runtime_version alpine_version; do
            sed -i "/\"netVersion\": \"${net_version}\"/,/}/s/\"sdkVersion\": \"[^\"]*\"/\"sdkVersion\": \"${sdk_version}\"/" image-matrix.json
            sed -i "/\"netVersion\": \"${net_version}\"/,/}/s/\"runtimeVersion\": \"[^\"]*\"/\"runtimeVersion\": \"${runtime_version}\"/" image-matrix.json
          done < updates.txt
          echo "Updated image-matrix.json"

          while IFS=: read -r net_version sdk_version runtime_version alpine_version; do
            sed -i -E "s/^\\|[[:space:]]*${net_version}[[:space:]]*\\|[[:space:]]*[[:digit:].]+[[:space:]]*\\|[[:space:]]*[[:digit:].]+[[:space:]]*\\|[[:space:]]*${net_version}-alpine[[:digit:].]+[[:space:]]*\\|/| ${net_version}          | ${sdk_version}     | ${runtime_version}          | ${net_version}-alpine${alpine_version} |/" README.md
          done < updates.txt
          echo "Updated README.md"

          # Update JOB.env
          current_defra_version=$(grep -oP 'DEFRA_VERSION=\K[\d.]+' JOB.env)
          new_defra_version=$(echo "$current_defra_version" | awk -F. '{print $1"."$2"."$3+1}')
          sed -i "s/DEFRA_VERSION=.*/DEFRA_VERSION=${new_defra_version}/" JOB.env
          echo "Updated JOB.env"

          # Update Dockerfile
          latest_net_version=$(jq -r '.[] | select(.latest == true) | .netVersion' image-matrix.json)
          latest_alpine_version=$(jq -r '.[] | select(.latest == true) | .alpineVersion' image-matrix.json)
          sed -i "s/ARG BASE_VERSION=.*/ARG BASE_VERSION=${latest_net_version}-alpine${latest_alpine_version}/" Dockerfile
          sed -i "s/ARG DEFRA_VERSION=.*/ARG DEFRA_VERSION=${new_defra_version}/" Dockerfile
          echo "Updated Dockerfile"

      - name: Prepare pull request details
        if: env.update_needed == 'true'
        run: |
          # Read updates.txt into an environment variable
          updated_versions=$(cat updates.txt | awk -F: '{print $1}' | sort -u | paste -sd, -)

          pull_request_title="Update .NET base image: ${updated_versions}"
          pull_request_body=$(cat updates.txt | awk -F: '{print "- .NET " $1 ": SDK " $2 ", Runtime " $3}')
          pull_request_branch="update-dotnet-base-image-${updated_versions//,/}"

          echo "pull_request_branch=${pull_request_branch}" >> $GITHUB_ENV
          echo "pull_request_title=${pull_request_title}" >> $GITHUB_ENV
          echo "pull_request_body<<EOF" >> $GITHUB_OUTPUT
          echo "$pull_request_body" >> $GITHUB_OUTPUT
          echo "EOF" >> $GITHUB_OUTPUT
          echo "Prepared pull request details."

      - name: Clean up temporary files
        if: env.update_needed == 'true'
        run: |
          rm -f releases-index.json updates.txt
          echo "Removed temporary files."

      - name: Generate GitHub App token
        if: env.update_needed == 'true'
        id: generate-token
        uses: tibdex/github-app-token@3beb63f4bd073e61482598c45c71c1019b59b73a # v2
        with:
          app_id: ${{ secrets.APP_ID }}
          private_key: ${{ secrets.APP_PRIVATE_KEY }}

      - name: Render PR template
        id: template
        uses: chuhlomin/render-template@a7c644e341797d050d1cb24332d83791b9a46dae # v1
        with:
          template: .github/pull_request_template.md

      - name: Create pull request
        if: env.update_needed == 'true'
        uses: peter-evans/create-pull-request@22a9089034f40e5a961c8808d113e2c98fb63676 # v7
        with:
          token: ${{ steps.generate-token.outputs.token }}
          branch: ${{ env.pull_request_branch }}
          base: main
          title: ${{ env.pull_request_title }}
          body: |
            Updates the .NET base images to the latest versions:
            ${{ steps.pr-details.outputs.pull_request_body }}
            ${{ steps.template.outputs.result }}
          sign-commits: true
          commit-message: ${{ env.pull_request_title }}
          team-reviewers: ${{ vars.PR_REVIEW_TEAM }}