AutopilotMonitor/.github/workflows/deploy-backend.yml

name: Deploy Backend (Azure Functions)

on:
  workflow_dispatch:

permissions:
  id-token: write   # OIDC federated login (secret-less)
  contents: read

env:
  FUNCTION_APP: autopilotmonitor-api-eu
  HEALTH_URL: https://autopilotmonitor-api-eu.azurewebsites.net/api/health
  VERSIONS_CONTAINER: https://autopilotmonitoreu.blob.core.windows.net/versions
  CSPROJ_PATH: src/Backend/AutopilotMonitor.Functions/AutopilotMonitor.Functions.csproj

jobs:
  build-and-deploy:
    runs-on: ubuntu-latest
    name: Build and Deploy Backend

    steps:
      - uses: actions/checkout@v7

      - name: Login to Azure (OIDC)
        uses: azure/login@v3
        with:
          client-id: ${{ secrets.AZURE_CLIENT_ID }}
          tenant-id: ${{ secrets.AZURE_TENANT_ID }}
          subscription-id: ${{ secrets.AZURE_SUBSCRIPTION_ID }}

      - name: Setup .NET 10
        uses: actions/setup-dotnet@v6
        with:
          dotnet-version: '10.0.x'

      # Same counter mechanism as the agent line: reserve-before-build with ETag-CAS
      # against a per-component counter blob. BuildTimestampUtc is pinned here rather
      # than left to MSBuild's default so the published manifest and the value baked
      # into the assembly (reported by /api/health) are the same instant.
      - name: Reserve build number (counter blob CAS)
        id: version
        shell: pwsh
        run: |
          $buildNumber = & ./.github/scripts/Request-BuildNumber.ps1 -CounterUrl "${{ env.VERSIONS_CONTAINER }}/backend.txt" -SasToken '${{ secrets.AZURE_BLOB_VERSIONS_SAS_TOKEN }}'

          $csproj = Get-Content ${{ env.CSPROJ_PATH }} -Raw
          if ($csproj -notmatch '<VersionPrefix>(\d+\.\d+)</VersionPrefix>') {
            throw "VersionPrefix not found in ${{ env.CSPROJ_PATH }}"
          }
          $version = "$($Matches[1]).$buildNumber"
          $buildUtc = [DateTime]::UtcNow.ToString('o')
          Write-Host "Backend version: $version (built $buildUtc)"

          "build_number=$buildNumber" >> $env:GITHUB_OUTPUT
          "version=$version" >> $env:GITHUB_OUTPUT
          "build_utc=$buildUtc" >> $env:GITHUB_OUTPUT

      - name: Restore dependencies
        run: dotnet restore ${{ env.CSPROJ_PATH }}

      - name: Build
        run: dotnet build ${{ env.CSPROJ_PATH }} --configuration Release --no-restore -p:SourceRevisionId=${{ github.sha }} -p:BuildNumber=${{ steps.version.outputs.build_number }} -p:BuildTimestampUtc=${{ steps.version.outputs.build_utc }}

      - name: Publish
        run: dotnet publish ${{ env.CSPROJ_PATH }} --configuration Release --output ./publish --no-build -p:SourceRevisionId=${{ github.sha }} -p:BuildNumber=${{ steps.version.outputs.build_number }} -p:BuildTimestampUtc=${{ steps.version.outputs.build_utc }}

      - name: Deploy to Azure Functions
        uses: Azure/functions-action@v1
        with:
          app-name: ${{ env.FUNCTION_APP }}
          package: ./publish

      # A green deploy step only means the package was accepted. This gate makes the
      # workflow assert what is actually being served, so the manifest published below
      # can be trusted as "this is live" rather than "this was uploaded".
      # /api/health is IP rate-limited at 30/min; one poll per 10s stays well under.
      - name: Verify deployed build is live
        shell: pwsh
        run: |
          $expectedCommit = '${{ github.sha }}'.Substring(0, 7)
          $expectedVersion = '${{ steps.version.outputs.version }}'
          $deadline = [DateTime]::UtcNow.AddMinutes(3)
          $attempt = 0

          while ([DateTime]::UtcNow -lt $deadline) {
            $attempt++
            try {
              $health = Invoke-RestMethod -Uri '${{ env.HEALTH_URL }}' -Method Get -TimeoutSec 30
              if ($health.commitHash -eq $expectedCommit -and $health.version -eq $expectedVersion) {
                Write-Host "Live after $attempt attempt(s): $($health.version) @ $($health.commitHash), built $($health.buildUtc)"
                exit 0
              }
              Write-Host "Attempt ${attempt}: serving $($health.version) @ $($health.commitHash) -- waiting for $expectedVersion @ $expectedCommit"
            } catch {
              Write-Host "Attempt ${attempt}: /api/health not answering yet -- $($_.Exception.Message)"
            }
            Start-Sleep -Seconds 10
          }

          throw "Backend did not report $expectedVersion @ $expectedCommit within 3 minutes -- deployment not verified, version manifest NOT published"

      # The manifest is the cross-component record of what is deployed where. It is
      # written last and only on a verified deploy, so a difference between the
      # manifest and /api/health means the running app drifted after the fact
      # (rollback, stale instance) rather than a half-finished pipeline.
      - name: Publish version manifest
        shell: pwsh
        run: |
          $manifest = [ordered]@{
            component   = 'backend'
            version     = '${{ steps.version.outputs.version }}'
            commit      = '${{ github.sha }}'.Substring(0, 7)
            buildUtc    = '${{ steps.version.outputs.build_utc }}'
            deployedUtc = [DateTime]::UtcNow.ToString('o')
            runId       = '${{ github.run_id }}'
          } | ConvertTo-Json

          $sas = '${{ secrets.AZURE_BLOB_VERSIONS_SAS_TOKEN }}'.TrimStart('?')
          $url = "${{ env.VERSIONS_CONTAINER }}/backend.json?$sas"
          # no-cache: rotating pointer, must never be served stale by any fronting cache.
          Invoke-RestMethod -Uri $url -Method Put -Headers @{ 'x-ms-blob-type' = 'BlockBlob'; 'x-ms-blob-cache-control' = 'no-cache' } -Body $manifest -ContentType 'application/json' | Out-Null
          Write-Host "Published versions/backend.json"
          Write-Host $manifest