Update LTS github actions (gloo-v1.6.x) (#152)

* Update LTS github actions
* re-introduce PR GHA

Author: sam-heilbron

.github/workflows/README.md

@@ -0,0 +1,47 @@
+# GitHub Workflows
+
+# Syncing LTS Branches
+
+Solo-Apis is a public, read-only mirror for API definitions. In order to keep API definitions in sync, we automate the process of syncing long term support (LTS) branches. 
+
+To keep the LTS branches unique, we prefix them with the name of the owner repo. For example, in gloo-edge the `1.8.x` LTS branch is tracked by the `gloo-1.8.x` LTS branch in solo-apis.
+
+#### How do Gloo Edge APIs get synced?
+
+1. A Gloo release occurs (ie v1.8.1 is released from LTS branch v1.8.x)
+1. A Gloo GHA generates the new APIs and pushes those to a branch (ie sync-apis/gloo-v1.8.x/gloo-v1.8.1)
+1. A [Solo-Apis GHA](#create-pr-for-lts-branch) notices that a commit was pushed to a `sync-apis` prefixed branch, and creates a PR.
+1. That PR is manually reviewed by a developer, and eventually approved
+1. A [Solo-Apis GHA](#tag-commit-on-lts-branch) notices that a commit is pushed to a LTS branch (ie gloo-v1.8.x) and tags the commit. This tag is referenced by other repositories.
+
+The GitHub actions that enable this process are defined below:
+
+## Create PR for LTS Branch
+
+The repo that owns API definitions is responsible for deciding when to update API definitions (ie after a release) and pushing the new API to a branch in solo-apis.
+
+This action only needs to know 2 pieces of information:
+1. The name of the LTS branch it should merge the code into
+1. The tag that should be applied to the merge commit
+
+We decided to use the branch name to pass this information. The workflow only operates on branches in the following format:
+```sync-apis/{LTS_BRANCH_NAME}/{LTS_TAG_NAME}```
+
+This allows the workflow to operate successfully, knowing the least information possible about the source repo that triggered the sync.
+
+The workflow has 2 responsibilities:
+1. To open a pull request to the LTS branch name
+1. To signify the tag that should be applied, when the PR merges
+
+The first step is easy, since the LTS branch is extracted from the branch name.
+The second step is more challenging since after the PR merges, the GitHub event that is triggered does not contain a reference to the name of the branch that merged. Therefore, we don't have a way to determine the name of the tag to apply. **We use a little trick to resolve this: providing a commit message with the tag included, and then extracting that commit message when generating a tag name.**
+
+
+*Note: This workflow opens a PR, but expects manual intervention by an engineer to approve the PR*
+
+## Tag Commit on LTS Branch
+
+After PRs are merged into LTS branches, we:
+1. Extract the latest commit message (which the above workflow provided)
+1. Determine the tag name from the commit message
+1. Push a tag name for that commit

.github/workflows/lts-branch-create-pull-request.yaml

@@ -0,0 +1,64 @@
+name: Create PR for LTS Branch
+on:
+  push:
+    branches:
+    - 'sync-apis/**/**'
+
+jobs:
+  create-pr-for-api-sync-branches:
+    runs-on: ubuntu-18.04
+    steps:
+      - name: Cancel Previous Actions
+        uses: styfle/[email protected]
+        with:
+          access_token: ${{ github.token }}
+      - name: Checkout Branch
+        uses: actions/checkout@v2
+      - name: Parse GitHub Ref
+        id: parse_github_ref
+        env:
+          DELIMITER: "/"
+          DEST_BRANCH_FIELD_NUMBER: 2
+          TAG_NAME_FIELD_NUMBER: 3
+          REF: ${{ github.ref }}
+          IGNORE_REF_PREFIX: 'refs/heads/'
+        run: |
+          echo "REF: $REF"
+
+          GITHUB_BRANCH_NAME=${REF#"$IGNORE_REF_PREFIX"}
+          echo "GITHUB_BRANCH_NAME: $GITHUB_BRANCH_NAME"
+
+          DESTINATION_BRANCH=$(echo $GITHUB_BRANCH_NAME | cut -f $DEST_BRANCH_FIELD_NUMBER -d $DELIMITER )
+          TAG_NAME=$(echo $GITHUB_BRANCH_NAME | cut -f $TAG_NAME_FIELD_NUMBER -d $DELIMITER )
+
+          echo "::set-output name=destination_branch::$(echo $DESTINATION_BRANCH )"
+          echo "::set-output name=tag_name::$(echo $TAG_NAME )"
+      - name: Setup Git
+        env:
+          GIT_USER_NAME: soloio-bot
+          GIT_USER_EMAIL: [email protected]
+        run: |
+          git config user.name $GIT_USER_NAME
+          git config user.email $GIT_USER_EMAIL
+      - name: Ensure LTS Branch Exists
+        env:
+          BRANCH: ${{ steps.parse_github_ref.outputs.destination_branch }}
+        run: |
+          git fetch origin
+          BRANCH_EXISTS=$(git ls-remote --heads origin $BRANCH)
+
+          if [[ -z ${BRANCH_EXISTS} ]]; then
+            echo "$BRANCH does not exist, creating it"
+            git push origin "HEAD:$BRANCH"
+          else
+            echo "$BRANCH exists, nothing to do"
+          fi
+      - name: Create Pull Request
+        uses: repo-sync/pull-request@v2
+        with:
+          destination_branch: ${{ steps.parse_github_ref.outputs.destination_branch }}
+          pr_reviewer: "solo-apis/solo-apis"
+          pr_label: "auto-pr"
+          pr_allow_empty: true
+          github_token: ${{ secrets.SOLO_BOT_REPO_SECRET }}
+          pr_title: "Sync APIs. @tag-name=${{ steps.parse_github_ref.outputs.tag_name }}"

.github/workflows/lts-branch-tag-commit.yaml

@@ -0,0 +1,35 @@
+name: Tag Commit on LTS Branch
+on:
+  push:
+    branches:
+      - master
+      - 'gloo-master'
+      - 'gloo-v**.**.x'
+jobs:
+  tag-version:
+    runs-on: ubuntu-latest
+    env:
+      # The regex of a commit produced by the soloio-bot
+      COMMIT_REGEX: "^.*(Sync APIs.)+.*$"
+    steps:
+      - name: Cancel Previous Actions
+        uses: styfle/[email protected]
+        with:
+          access_token: ${{ github.token }}
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: '0'
+      - name: Parse out tag name from commit message
+        id: tag_version
+        run: |
+          if [[ $(git log -1 --oneline) =~ ${{ env.COMMIT_REGEX }} ]]; then
+            TAG_NAME=$(git log -1 --oneline | awk -F'@tag-name=' '{print $2}' | awk -F' ' '{print $1}')
+          fi
+          echo "::set-output name=tag_name::$(echo $TAG_NAME)"
+      - name: Bump version and push tag
+        if: steps.tag_version.outputs.tag_name != ''
+        uses: anothrNick/[email protected]
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          CUSTOM_TAG: ${{ steps.tag_version.outputs.tag_name }}
+          RELEASE_BRANCHES: '*master,gloo-**.**.x'

.github/workflows/pull_request.yaml

@@ -1,9 +1,6 @@
 name: pull_request
 
 on:
-  push:
-    branches:
-    - 'master'
   pull_request:
 
 jobs: