Update Eng/Common Workflow

eng/common/README.md

@@ -9,4 +9,15 @@ should not contain binary files as they don't play well with git.
 Any updates to files in the `eng/common` directory should be made in the [azure-sdk-tools](https://github.com/azure/azure-sdk-tools) repo.
 All changes made will cause a PR to created in all subscribed azure-sdk language repos which will blindly replace all contents of
 the `eng/common` directory in that repo. For that reason do **NOT** make changes to files in this directory in the individual azure-sdk
-languages repos as they will be overwritten the next time an update is taken from the common azure-sdk-tools repo.
+languages repos as they will be overwritten the next time an update is taken from the common azure-sdk-tools repo.
+
+### Workflow
+
+The 'Sync eng/common directory' PRs will be created in the language repositories once a pull request that touches the eng/common directory is submitted against the master branch. This will make it easier for changes to be tested in each individual language repo before merging the changes in the azure-sdk-tools repo. The workflow is explained below:
+
+1. Create a PR against Azure/azure-sdk-tools:master. This is the **Tools PR**.
+2. `azure-sdk-tools - sync - eng-common` is run automatically. It creates **Sync PRs** in each of the connected language repositories using the format `Sync eng/common directory with azure-sdk-tools for PR {Tools PR Number}`. Each **Sync PR** will contain a link back to the **Tools PR** that triggered it.
+3. More changes pushed to the **Tools PR**, will automatically triggered new pipeline runs in the respective **Sync PRs**. The **Sync PRs** are used to make sure the changes would not break any of the connected pipelines.
+4. Once satisfied with the changes;
+    - First merge all the **Sync PRs**. The **Tools PR** contains links to all the **Sync PRs**
+    - Finally merge the **Tools PR**. Each **Sync PR** contains the link to the corresponding **Tools PR**. 

eng/common/pipelines/templates/steps/create-pull-request.yml

@@ -11,6 +11,7 @@ parameters:
   PushArgs:
   WorkingDirectory: $(System.DefaultWorkingDirectory)
   PRTitle: not-specified
+  PRBody: not-specified 
   ScriptDirectory: eng/common/scripts
   GHReviewersVariable: '' 
   GHTeamReviewersVariable: ''
@@ -65,6 +66,7 @@ steps:
       -PRBranch "${{ parameters.PRBranchName }}"
       -AuthToken "$(azuresdk-github-pat)"
       -PRTitle "${{ parameters.PRTitle }}"
+      -PRBody "${{ parameters.PRBody }}"
 
 - task: PowerShell@2
   displayName: Tag a Reviewer on PR

eng/common/scripts/Submit-PullRequest.ps1

@@ -38,7 +38,8 @@ param(
 
   [Parameter(Mandatory = $true)]
   $PRTitle,
-  $PRBody = $PRTitle
+
+  $PRBody=$PRTitle
 )
 
 $headers = @{

eng/pipelines/eng-common-sync.yml

@@ -24,6 +24,9 @@ jobs:
         DirectoryToSync: "eng/common"
         PRBranchName: "sync-eng-common-$(System.PullRequest.SourceBranch)-$(System.PullRequest.PullRequestNumber)"
         PRTitle: "Sync eng/common directory with azure-sdk-tools for PR $(System.PullRequest.PullRequestNumber)"
+        PRBody: >- 
+          Sync eng/common directory with azure-sdk-tools for PR https://github.com/Azure/azure-sdk-tools/pull/$(System.PullRequest.PullRequestNumber) <br>
+          See [eng/common workflow](https://github.com/Azure/azure-sdk-tools/blob/master/eng/common/README.md#workflow)
         Repos:
           - azure-sdk-for-android
           - azure-sdk-for-c

eng/pipelines/templates/steps/sync-directory.yml

@@ -5,6 +5,7 @@ parameters:
   PRBranchName: branch-name-not-set
   BaseBranchName: master
   PRTitle: pr-title-not-set
+  PRBody: pr-body-not-set
 
 steps:
 
@@ -28,6 +29,7 @@ steps:
       BaseBranchName: ${{ parameters.BaseBranchName }}
       CommitMsg: ${{ parameters.CommitMessage }}
       PRTitle: ${{ parameters.PRTitle }}
+      PRBody: ${{ parameters.PRBody }}
       PushArgs: -f
       WorkingDirectory: $(System.DefaultWorkingDirectory)/${{ repo }}
       ScriptDirectory: $(System.DefaultWorkingDirectory)/eng/common/scripts