Add noCache parameter to pipelines (#1515)

Author: mthalman

eng/pipelines/dotnet-buildtools-prereqs-official.yml

@@ -22,6 +22,15 @@ parameters:
   type: string
   default: $(Build.BuildId)
 
+- name: noCache
+  displayName: >
+    Run build with no cache. When this is unchecked, the build will use the
+    info in the dotnet/versions repo to build only the images which have had
+    Dockerfile changes or base images updates. When this is checked, all images
+    will be built regardless of caching status.
+  type: boolean
+  default: false
+
 schedules:
 - cron: "0 5 1,15 * *"
   displayName: Monthly rebuild of all images
@@ -60,3 +69,4 @@ extends:
       parameters:
         sourceBuildPipelineRunId: ${{ parameters.sourceBuildPipelineRunId }}
         publishConfigTemplatePath: /eng/common/templates/stages/dotnet/publish-config-prod.yml@self
+        noCache: ${{ parameters.noCache }}

eng/pipelines/dotnet-buildtools-prereqs-unofficial.yml

@@ -16,6 +16,15 @@ parameters:
   type: string
   default: $(Build.BuildId)
 
+- name: noCache
+  displayName: >
+    Run build with no cache. When this is unchecked, the build will use the
+    info in the dotnet/versions repo to build only the images which have had
+    Dockerfile changes or base images updates. When this is checked, all images
+    will be built regardless of caching status.
+  type: boolean
+  default: false
+
 variables:
 - template: /eng/pipelines/variables/common.yml@self
   parameters:
@@ -43,3 +52,4 @@ extends:
       parameters:
         sourceBuildPipelineRunId: ${{ parameters.sourceBuildPipelineRunId }}
         publishConfigTemplatePath: /eng/common/templates/stages/dotnet/publish-config-nonprod.yml@self
+        noCache: ${{ parameters.noCache }}

eng/pipelines/stages/dotnet-buildtools-prereqs.yml

@@ -3,6 +3,10 @@ parameters:
   type: string
   default: $(Build.BuildId)
 
+- name: noCache
+  type: boolean
+  default: false
+
 - name: publishConfigTemplatePath
   type: string
 
@@ -38,6 +42,8 @@ stages:
       # See https://github.com/dotnet/dotnet-buildtools-prereqs-docker/issues/1224
       ${{ if eq(variables['Build.Reason'], 'Schedule') }}:
         noCache: true
+      ${{ else }}:
+        noCache: ${{ parameters.noCache }}
       ${{ if contains(variables['Build.DefinitionName'], '-official') }}:
         additionalServiceConnections:
         - name: $(marStatus.serviceConnectionName)