github: add pull request endpoint (bug 1991125)

src/lando/api/views.py

@@ -9,15 +9,22 @@
 from django.views import View
 from django.views.decorators.csrf import csrf_exempt
 
-from lando.main.models import CommitMap
+from lando.main.models import CommitMap, Repo
 from lando.main.models.revision import DiffWarning, DiffWarningStatus
 from lando.main.scm import (
     SCM_TYPE_GIT,
     SCM_TYPE_HG,
 )
+from lando.utils.github import GitHubAPIClient, PullRequest
 from lando.utils.phabricator import get_phabricator_client
 
 
+class APIView(View):
+    """A base class for API views."""
+
+    pass
+
+
 def phabricator_api_key_required(func: callable) -> Callable:
     """A simple wrapper that checks for a valid Phabricator API token."""
 
@@ -148,3 +155,22 @@ class hg2gitCommitMapView(CommitMapBaseView):
     """Return corresponding CommitMap given an hg hash."""
 
     scm = SCM_TYPE_HG
+
+
+class PullRequestAPIView(APIView):
+    """Handle pull requests in the API."""
+
+    def get(self, request: WSGIRequest, repo_name: str, number: int) -> JsonResponse:
+        """Return a serialized JSON representation of a pull request."""
+        target_repo = Repo.objects.get(name=repo_name)
+        client = GitHubAPIClient(target_repo)
+        pull_request = PullRequest(client.get_pull_request(number))
+        return JsonResponse(pull_request.serialize(), status=200)
+
+
+class LandingJobAPIView(View):
+    """Handle landing jobs in the API."""
+
+    def post(self, request: WSGIRequest, *args, **kwargs):
+        """Placeholder for creating new landing jobs."""
+        pass

src/lando/urls.py

@@ -21,6 +21,7 @@
 from lando.api.legacy.api import landing_jobs
 from lando.api.views import (
     LegacyDiffWarningView,
+    PullRequestAPIView,
     git2hgCommitMapView,
     hg2gitCommitMapView,
 )
@@ -85,6 +86,14 @@
     ),
 ]
 
+urlpatterns += [
+    path(
+        "api/pulls/<str:repo_name>/<int:number>",
+        PullRequestAPIView.as_view(),
+        name="api-pull-request",
+    ),
+]
+
 # "API" endpoints ported from legacy API app.
 urlpatterns += [
     path(

src/lando/utils/github.py

@@ -146,3 +146,36 @@ def __init__(self, data: dict):
         self.user_id = data["user"]["id"]
         self.user_html_url = data["user"]["html_url"]
         self.user_login = data["user"]["login"]
+
+    def serialize(self) -> dict[str, str]:
+        """Return a dictionary with various pull request data."""
+        return {
+            "url": self.url,
+            "base_ref": self.base_ref,
+            "base_sha": self.base_sha,
+            "base_user_login": self.base_user_login,
+            "base_user_id": self.base_user_id,
+            "created_at": self.created_at,
+            "updated_at": self.updated_at,
+            "closed_at": self.closed_at,
+            "merged_at": self.merged_at,
+            "diff_url": self.diff_url,
+            "patch_url": self.patch_url,
+            "body": self.body,
+            "is_draft": self.is_draft,
+            "comments_url": self.comments_url,
+            "commits_url": self.commits_url,
+            "head_ref": self.head_ref,
+            "head_sha": self.head_sha,
+            "head_repo_git_url": self.head_repo_git_url,
+            "html_url": self.html_url,
+            "id": self.id,
+            "number": self.number,
+            "requested_reviewers": self.requested_reviewers,
+            "requested_teams": self.requested_teams,
+            "state": self.state,
+            "title": self.title,
+            "user_id": self.user_id,
+            "user_html_url": self.user_html_url,
+            "user_login": self.user_login,
+        }