Delete a branch when PR is closed. (GH-24)

Author: Mariatta

backport/delete_branch.py

@@ -0,0 +1,21 @@
+import gidgethub.routing
+
+from . import util
+
+router = gidgethub.routing.Router()
+
+
+@router.register("pull_request", action="closed")
+async def delete_branch(event, gh, *args, **kwargs):
+    """
+    Delete the branch once PR is closed.
+    Say thanks if it's merged.
+    """
+    if event.data["pull_request"]["merged"]:
+        issue_number = event.data['pull_request']['number']
+        merged_by = event.data['pull_request']['merged_by']['login']
+        util.comment_on_pr(issue_number, f"Thanks, @{merged_by}!")
+
+    branch_name = event.data['pull_request']['head']['ref']
+    util.delete_branch(branch_name)
+

backport/util.py

@@ -46,3 +46,18 @@ def get_participants(created_by, merged_by):
     else:
         participants = f"@{created_by} and @{merged_by}"
     return participants
+
+
+def delete_branch(branch_name):
+    """
+    Delete the branch on GitHub
+    """
+    request_headers = sansio.create_headers(
+        "miss-islington",
+        oauth_token=os.environ.get('GH_AUTH'))
+    url = f"https://github.com/api/repos/miss-islington/cpython/git/refs/heads/{branch_name}"
+    response = requests.delete(url, headers=request_headers)
+    if response.status_code == 204:
+        print(f"{branch_name} branch deleted.")
+    else:
+        print(f"Couldn't delete the branch {branch_name}")