Converted set-cicd-flag to a YAML template with inline script (#325)

* Converted set-cicd-flag to a YAML template with inline script

* Removed replaced script.

devops/providers/azure-devops/templates/infrastructure/azure-pipeline-build-stage.yml

@@ -15,14 +15,10 @@ jobs:
 
   steps:
   - ${{ each config in parameters.configurationMatrix }}:
-    - task: Bash@3
-      name: ${{ config.jobName }}
-      displayName: Determine if ${{ config.jobName }} needs CI
-      inputs:
-        filePath: './$(PIPELINE_ROOT_DIR)/$(SCRIPTS_DIR)/set-cicd-flag.sh'
-        workingDirectory: $(Build.SourcesDirectory)
-      env:
-        TERRAFORM_TEMPLATE_PATH: '${{ config.terraformTemplatePath }}'
+    - template: scripts/set-cicd-flag.yml
+      parameters:
+        terraformTemplatePath: ${{ config.terraformTemplatePath }}
+        jobName: ${{ config.jobName }}
 
 - ${{ each config in parameters.configurationMatrix }}:
   - job: Build_${{ config.jobName }}_${{ parameters.environment }}

devops/providers/azure-devops/templates/infrastructure/azure-pipeline-release-stage.yml

@@ -14,14 +14,10 @@ jobs:
   condition: not(coalesce(variables.FORCE_RUN, ${{ parameters.forceRun }}))
   steps:
   - ${{ each config in parameters.configurationMatrix }}:
-    - task: Bash@3
-      name: ${{ config.jobName }}
-      displayName: Determine if ${{ config.jobName }} needs CD
-      inputs:
-        filePath: './$(PIPELINE_ROOT_DIR)/$(SCRIPTS_DIR)/set-cicd-flag.sh'
-        workingDirectory: $(Build.SourcesDirectory)
-      env:
-        TERRAFORM_TEMPLATE_PATH: '${{ config.terraformTemplatePath }}'
+    - template: scripts/set-cicd-flag.yml
+      parameters:
+        terraformTemplatePath: ${{ config.terraformTemplatePath }}
+        jobName: ${{ config.jobName }}
 
 - ${{ each config in parameters.configurationMatrix }}:
   - deployment: Provision_${{ config.jobName }}_${{ parameters.environment }}

devops/providers/azure-devops/templates/infrastructure/scripts/set-cicd-flag.yml

@@ -0,0 +1,59 @@
+parameters:
+  terraformTemplatePath: ''
+  jobName: ''
+
+steps:
+  - task: Bash@3
+    name: ${{ parameters.jobName }}
+    displayName: Determine if ${{ parameters.jobName }} needs CI/CD
+    env:
+      TERRAFORM_TEMPLATE_PATH: ${{ parameters.terraformTemplatePath }}
+    inputs:
+      targetType: 'inline'
+      script: |
+        #!/usr/bin/env bash
+
+        # Note: Omitting `set -euo pipefail` as it makes using grep to filter for changes a nightmare!
+
+        declare readonly GIT_DIFF_EXTENSION_WHITE_LIST="*.go|*.tf|*.sh|Dockerfile*|*.tfvars|*.yaml|*.yml"
+
+        function setCICDFlag() {
+            echo "Template $TERRAFORM_TEMPLATE_PATH needs CI/CD"
+            echo "##vso[task.setvariable variable=needs_cicd;isOutput=true]true"
+        }
+
+        MASTER="remotes/origin/master"
+        GIT_DIFF_SOURCEBRANCH="HEAD"
+
+        # we should always use master as a comparison, except in the case that this is
+        # a build for master. In this case we can use HEAD~ (1 commit behind master)
+        # because all merges will be squash merges
+        if [[ $(git diff "$MASTER") ]]; then
+            GIT_DIFF_UPSTREAMBRANCH="$MASTER"
+        else
+            GIT_DIFF_UPSTREAMBRANCH="$MASTER~"
+        fi
+
+        echo "GIT_DIFF_UPSTREAMBRANCH: $GIT_DIFF_UPSTREAMBRANCH"
+        echo "GIT_DIFF_SOURCEBRANCH: $GIT_DIFF_SOURCEBRANCH"
+
+        FILE_CHANGE_SET=$(git diff "$GIT_DIFF_SOURCEBRANCH" "$GIT_DIFF_UPSTREAMBRANCH" --name-only)
+        echo "Files changed since last commit..."
+        echo "$FILE_CHANGE_SET"
+
+        FILTERED_FILE_CHANGE_SET=$(grep -E "$GIT_DIFF_EXTENSION_WHITE_LIST" <<< "$FILE_CHANGE_SET" || true)
+        echo "Files changed since last commit, filtered for build-relevant files..."
+        echo "$FILTERED_FILE_CHANGE_SET"
+
+        TEST_HARNESS_CHANGES=$(grep "$TEST_HARNESS_DIR" <<< "$FILTERED_FILE_CHANGE_SET" || true)
+        TEMPLATE_CHANGES=$(grep "$TERRAFORM_TEMPLATE_PATH" <<< "$FILTERED_FILE_CHANGE_SET" || true)
+        PIPELINE_CHANGES=$(grep "$PIPELINE_ROOT_DIR" <<< "$FILTERED_FILE_CHANGE_SET" || true)
+        MODULE_CHANGES=$(grep "$TF_ROOT_DIR/modules" <<< "$FILTERED_FILE_CHANGE_SET" || true)
+
+        # if relevant files have been changed, CICD for this template needs to run
+        [ ! -z "${TEST_HARNESS_CHANGES}" ] && setCICDFlag
+        [ ! -z "${TEMPLATE_CHANGES}" ] && setCICDFlag
+        [ ! -z "${PIPELINE_CHANGES}" ] && setCICDFlag
+        [ ! -z "${MODULE_CHANGES}" ] && setCICDFlag
+
+        exit 0