Add examples

Author: peter-evans

README.md

@@ -24,7 +24,7 @@ Dispatching commands to be processed elsewhere keeps the workflow queue moving q
 - Long running workloads can be processed in a repository workflow queue of their own
 - Even if commands are dispatched and processed in the same repository, separation of comment parsing and command processing makes workflows more maintainable, and with less duplication
 
-### Demo
+### Demo and examples
 
 The best way to understand how this works is to try it out for yourself.
 Check out the following demos.
@@ -33,6 +33,8 @@ Check out the following demos.
 - [ChatOps Demo in Pull Requests](https://github.com/peter-evans/slash-command-dispatch/pull/8)
 - [Slash command code formatting - Python](https://github.com/peter-evans/slash-command-dispatch/pull/11)
 
+See [examples](examples.md) for command patterns and example workflows.
+
 ## Dispatching commands
 
 ### Basic configuration

examples.md

@@ -0,0 +1,99 @@
+# Examples
+
+This document details some command patterns and examples.
+
+- [Use case: Execute command using a specific repository branch](#execute-command-using-a-specific-repository-branch)
+- [Use case: Execute command to modify a pull request branch](#execute-command-to-modify-a-pull-request-branch)
+
+## Use case: Execute command using a specific repository branch
+
+This is pattern for a slash command where the first argument is the branch to checkout. If no argument is given it defaults to `master`. For example, the following command will cause the command workflow to checkout the `develop` branch of the repository where the command was dispatched from. After the branch has been checked out in the command workflow, scripts or actions may be executed against it.
+
+```
+/do-something develop
+```
+
+In the following command workflow, `REPO_ACCESS_TOKEN` is a `repo` scoped [Personal Access Token](https://help.github.com/en/github/authenticating-to-github/creating-a-personal-access-token-for-the-command-line).
+
+```yml
+name: do-something-command
+on:
+  repository_dispatch:
+    types: [do-something-command]
+jobs:
+  doSomething:
+    runs-on: ubuntu-latest
+    steps:
+      # Get the branch name
+      - name: Get the target branch name
+        id: vars
+        run: |
+          branch=${{ github.event.client_payload.slash_command.arg1 }}
+          if [[ -z "$branch" ]]; then branch="master"; fi
+          echo ::set-output name=branch::$branch
+
+      # Checkout the branch to test
+      - uses: actions/checkout@v2
+        with:
+          token: ${{ secrets.REPO_ACCESS_TOKEN }}
+          repository: ${{ github.event.client_payload.github.payload.repository.full_name }}
+          ref: ${{ steps.vars.outputs.branch }}
+
+      # Execute scripts or actions
+      - name: Do something
+        run: echo "Do something"
+
+      # Add reaction to the comment
+      - name: Add reaction
+        uses: peter-evans/create-or-update-comment@v1
+        with:
+          token: ${{ secrets.REPO_ACCESS_TOKEN }}
+          repository: ${{ github.event.client_payload.github.payload.repository.full_name }}
+          comment-id: ${{ github.event.client_payload.github.payload.comment.id }}
+          reaction-type: hooray
+```
+
+## Use case: Execute command to modify a pull request branch
+
+This is pattern for a slash command used in pull request comments. It checks out the pull request branch and allows further script and action steps to modify it.
+
+```
+/fix-pr
+```
+
+In the following command workflow, `REPO_ACCESS_TOKEN` is a `repo` scoped [Personal Access Token](https://help.github.com/en/github/authenticating-to-github/creating-a-personal-access-token-for-the-command-line).
+
+```yml
+name: fix-pr-command
+on:
+  repository_dispatch:
+    types: [fix-pr-command]
+jobs:
+  fixPr:
+    runs-on: ubuntu-latest
+    steps:
+      # Checkout the pull request branch
+      - uses: actions/checkout@v2
+        with:
+          token: ${{ secrets.REPO_ACCESS_TOKEN }}
+          repository: ${{ github.event.client_payload.pull_request.head.repo.full_name }}
+          ref: ${{ github.event.client_payload.pull_request.head.ref }}
+
+      # Commit changes to the PR branch
+      - name: Commit changes to the PR branch
+        run: |
+          # TODO Make changes to commit here
+          #
+          git config --global user.name 'actions-bot'
+          git config --global user.email '58130806+actions-bot@users.noreply.github.com'
+          git commit -am "[fix-pr-command] fixes"
+          git push
+
+      - name: Add reaction
+        uses: peter-evans/create-or-update-comment@v1
+        with:
+          token: ${{ secrets.REPO_ACCESS_TOKEN }}
+          repository: ${{ github.event.client_payload.github.payload.repository.full_name }}
+          comment-id: ${{ github.event.client_payload.github.payload.comment.id }}
+          reaction-type: hooray
+```