Add option to specify PR as raw payload JSON

In addition to using the four separate `pr_*` arguments, PR information
can now be specified as a raw JSON representation of a PR webhook
payload. This makes it easier to specify the correct arguments and is
more flexible when the payload is received from an API call.

Author: SebastiaanZ

action.yaml

@@ -59,6 +59,10 @@ inputs:
     description: 'source of the Pull Request'
     required: false
 
+  pull_request_payload:
+    description: 'Pull Request in jSON payload form'
+    required: false
+
 runs:
   using: 'docker'
   image: 'Dockerfile'

github_status_embed/__main__.py

@@ -76,7 +76,10 @@
     # Extract Action arguments by creating dataclasses
     workflow = Workflow.from_arguments(arguments)
     webhook = Webhook.from_arguments(arguments)
-    pull_request = PullRequest.from_arguments(arguments)
+    if arguments.get("pull_request_payload", False):
+        pull_request = PullRequest.from_payload(arguments)
+    else:
+        pull_request = PullRequest.from_arguments(arguments)
 
     # Send webhook
     success = send_webhook(workflow, webhook, pull_request, dry_run)

github_status_embed/types.py

@@ -2,8 +2,11 @@
 
 import dataclasses
 import enum
+import json
+import logging
 import typing
 
+log = logging.getLogger(__name__)
 
 MIN_EMBED_FIELD_LENGTH = 20
 
@@ -199,6 +202,39 @@ class PullRequest(TypedDataclass, optional=True):
     pr_title: str
     pr_source: str
 
+    @classmethod
+    def from_payload(cls, arguments: typing.Dict[str, str]) -> typing.Optional[PullRequest]:
+        """Create a Pull Request instance from Pull Request Payload JSON."""
+        # Safe load the JSON Payload provided as a command line argument.
+        raw_payload = arguments.pop('pull_request_payload')
+        log.debug(f"Attempting to parse PR Payload JSON: {raw_payload!r}.")
+        try:
+            payload = json.loads(raw_payload)
+        except json.JSONDecodeError:
+            log.debug("Failed to parse JSON, dropping down to empty payload")
+            payload = {}
+        else:
+            log.debug("Successfully parsed parsed payload")
+
+        # If the payload contains multiple PRs in a list, use the first one.
+        if isinstance(payload, list):
+            log.debug("The payload contained a list, extracting first PR.")
+            payload = payload[0] if payload else {}
+
+        if not payload:
+            log.warning("PR payload could not be parsed, attempting regular pr arguments.")
+            return cls.from_arguments(arguments)
+
+        # Get the target arguments from the payload, yielding similar results
+        # when keys are missing as to when their corresponding arguments are
+        # missing.
+        arguments["pr_author_login"] = payload.get('user', {}).get('login', '')
+        arguments["pr_number"] = payload.get('number', '')
+        arguments["pr_title"] = payload.get('title', '')
+        arguments["pr_source"] = payload.get('head', {}).get('label', '')
+
+        return cls.from_arguments(arguments)
+
     @property
     def author(self) -> str:
         """Return the `pr_author_login` field."""