From aec2c2f997a8d160a6458be20df52596019c3bb0 Mon Sep 17 00:00:00 2001
From: agneszitte <agnes@platform.uno>
Date: Wed, 27 Mar 2024 21:07:05 -0400
Subject: [PATCH] ci: Adjust CI Build for Doc-Only PRs validations

---
 azure-pipelines.yml                           | 30 +++++---
 build/stage-determine-changes.yml             | 70 +++++++++++++++++++
 ...dations.yml => stage-docs-validations.yml} |  0
 3 files changed, 89 insertions(+), 11 deletions(-)
 create mode 100644 build/stage-determine-changes.yml
 rename build/{stage-validations.yml => stage-docs-validations.yml} (100%)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index cf86ba553..f5589a07c 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -12,9 +12,6 @@
     - '/'
     exclude:
     - .github/
-    # don't trigger the CI if only docs files are changed
-    - doc/*
-    - '**/*.md'
 
 pr: 
   branches:
@@ -30,9 +27,6 @@ pr:
     - '/'
     exclude:
     - .github/
-    # don't trigger the CI if only docs files are changed
-    - doc/*
-    - '**/*.md'
 
 variables:
   # Path where packages (nuget or app packages) will be copied to.
@@ -49,18 +43,32 @@ variables:
   # AndroidNdkDirectory: C:\Microsoft\AndroidNDK64\android-ndk-r16b
 
 stages:
-- stage: Validations
-  displayName: Validations
+- stage: Determine_Changes
+  displayName: Determine Changes
   jobs:
-  - template: build/stage-validations.yml
+  - template: build/stage-determine-changes.yml
+
+- stage: Docs_Validations
+  displayName: Docs Validations
+  dependsOn: Determine_Changes
+  # Trigger this stage when docs files are changed
+  condition: or(eq(dependencies.Determine_Changes.outputs['evaluate_changes.DetermineChanges.docsOnly'], 'true'), eq(dependencies.Determine_Changes.outputs['evaluate_changes.DetermineChanges.mixedChanges'], 'true'))
+  jobs:
+  - template: build/stage-docs-validations.yml
 
 - stage: Packages
-  dependsOn: Validations
+  displayName: Packages
+  dependsOn: Determine_Changes
+  # Don't trigger this stage if only docs files are changed
+  condition: eq(dependencies.Determine_Changes.outputs['evaluate_changes.DetermineChanges.nonDocsOnly'], 'true')
   jobs:
   - template: build/stage-build-packages.yml
 
 - stage: Build_Samples
-  dependsOn: Validations
+  displayName: Build Samples
+  dependsOn: Determine_Changes
+  # Don't trigger this stage if only docs files are changed
+  condition: eq(dependencies.Determine_Changes.outputs['evaluate_changes.DetermineChanges.nonDocsOnly'], 'true')
   jobs:
     - template: build/stage-build-ios.yml
     - template: build/stage-build-android.yml
diff --git a/build/stage-determine-changes.yml b/build/stage-determine-changes.yml
new file mode 100644
index 000000000..48d28ff44
--- /dev/null
+++ b/build/stage-determine-changes.yml
@@ -0,0 +1,70 @@
+jobs:
+- job: evaluate_changes
+  displayName: 'Check for Doc Only Changes'
+  pool:
+    vmImage: 'ubuntu-latest'
+  steps:
+  - powershell: |
+      # Determine the context of the build (PR or push) and set the target branch accordingly
+      $prTargetBranch = "$(System.PullRequest.TargetBranch)"
+      $isPR = -not [string]::IsNullOrWhiteSpace($prTargetBranch)
+
+      # Normalize the target branch name for PR builds or default to 'master' for push builds
+      $targetBranchName = $isPR ? $prTargetBranch -replace 'refs/heads/', '' : "master"
+
+      Write-Host "Build context determined: $(if ($isPR) { 'Pull Request targeting ' + $targetBranchName } else { 'Push' })"
+
+      # Fetch the target or default base branch and determine the merge base
+      git fetch origin $targetBranchName
+      $mergeBase = git merge-base HEAD "origin/$targetBranchName"
+      Write-Host "Merge base with '$targetBranchName' identified at $mergeBase"
+
+      Write-Host "Comparing changes from $mergeBase..."
+      $gitDiffCommand = "git diff $mergeBase --name-only"
+      $changedFiles = Invoke-Expression $gitDiffCommand
+      $docsOnly = $false
+      $nonDocsOnly = $false
+      $mixedChanges = $false
+      $docFiles = 0
+      $nonDocFiles = 0
+
+      if ($changedFiles) {
+          Write-Host "Changed files:"
+          Write-Host $changedFiles
+      } else {
+          Write-Host "No files have changed."
+      }
+
+      foreach ($file in $changedFiles -split "`n") {
+          if ($file.EndsWith(".md") -or $file -like "*/toc.yml") {
+              $docFiles++
+          } else {
+              $nonDocFiles++
+          }
+      }
+
+      Write-Host "Documentation files changed: $docFiles"
+      Write-Host "Non-documentation files changed: $nonDocFiles"
+
+      if ($docFiles -gt 0 -and $nonDocFiles -eq 0) {
+          $docsOnly = $true
+          Write-Host "All changes are documentation-only."
+      } elseif ($docFiles -gt 0 -and $nonDocFiles -gt 0) {
+          $mixedChanges = $true
+          Write-Host "Mixed changes detected: Both documentation and non-documentation files have been modified."
+      } elseif ($nonDocFiles -gt 0) {
+          $nonDocsOnly = $true
+          Write-Host "Non-documentation changes detected."
+      }
+
+      # Explicitly write the final values for clarity
+      Write-Host "Final values:"
+      Write-Host "docsOnly: $docsOnly"
+      Write-Host "nonDocsOnly: $nonDocsOnly"
+      Write-Host "mixedChanges: $mixedChanges"
+
+      # Output the results as pipeline variables
+      Write-Host "##vso[task.setvariable variable=docsOnly;isOutput=true]$docsOnly"
+      Write-Host "##vso[task.setvariable variable=nonDocsOnly;isOutput=true]$nonDocsOnly"
+      Write-Host "##vso[task.setvariable variable=mixedChanges;isOutput=true]$mixedChanges"
+    name: DetermineChanges
\ No newline at end of file
diff --git a/build/stage-validations.yml b/build/stage-docs-validations.yml
similarity index 100%
rename from build/stage-validations.yml
rename to build/stage-docs-validations.yml