Implement received Webmention handling

Add the Flask application setup, database models and migrations,
authentication, and configuration for development and testing.

Implement asynchronous Webmention verification with Huey, including HTML
and plain-text source validation, retries, status tracking, and size
limits.

Add status, login, and paginated received-Webmention views together with
comprehensive tests for forms, views, and receiver tasks.

1 files changed, 183 insertions, 0 deletions

diff --git a/tests/test_views.py b/tests/test_views.py
new file mode 100644
index 0000000..d7fd798
--- /dev/null
+++ b/tests/test_views.py
@@ -0,0 +1,183 @@
+import uuid
+from types import ModuleType
+
+import pytest
+import sqlalchemy as sa
+from flask import Flask
+from flask.testing import FlaskClient
+
+from webmentions_ssg import DATABASE as db
+from webmentions_ssg.models import ReceivedWebmention
+
+
+def test_endpoint_only_accepts_post(
+    client: FlaskClient,
+) -> None:
+    response = client.get("/endpoint")
+
+    assert response.status_code == 405
+
+
+def test_endpoint_returns_form_errors(
+    client: FlaskClient,
+) -> None:
+    response = client.post(
+        "/endpoint",
+        data={
+            "source": "https://source.example/post",
+            "target": "https://example.com/post",
+        },
+    )
+
+    assert response.status_code == 400
+
+    errors = response.get_json()
+
+    assert errors is not None
+    assert "target" in errors
+
+
+def test_endpoint_creates_webmention(
+    app: Flask,
+    client: FlaskClient,
+    views_module: ModuleType,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    queued: list[uuid.UUID] = []
+
+    monkeypatch.setattr(
+        views_module,
+        "verify_webmention",
+        queued.append,
+    )
+
+    source = "https://source.example/post"
+    target = "https://dennisfink.me/blog/example/"
+
+    response = client.post(
+        "/endpoint",
+        data={
+            "source": source,
+            "target": target,
+        },
+    )
+
+    assert response.status_code == 201
+
+    with app.app_context():
+        webmention = db.session.scalar(sa.select(ReceivedWebmention))
+
+        assert webmention is not None
+        assert webmention.source == source
+        assert webmention.target == target
+        assert webmention.status == "received"
+        assert webmention.failure_reason is None
+
+        identifier = webmention.uuid
+
+    assert response.headers["Location"].endswith(str(identifier))
+
+    assert queued == [identifier]
+
+
+def test_endpoint_is_idempotent(
+    app: Flask,
+    client: FlaskClient,
+    views_module: ModuleType,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    queued: list[uuid.UUID] = []
+
+    monkeypatch.setattr(
+        views_module,
+        "verify_webmention",
+        queued.append,
+    )
+
+    data = {
+        "source": ("https://source.example/post"),
+        "target": ("https://dennisfink.me/blog/example/"),
+    }
+
+    first_response = client.post(
+        "/endpoint",
+        data=data,
+    )
+    second_response = client.post(
+        "/endpoint",
+        data=data,
+    )
+
+    assert first_response.status_code == 201
+    assert second_response.status_code == 201
+
+    assert first_response.headers["Location"] == second_response.headers["Location"]
+
+    with app.app_context():
+        webmentions = db.session.scalars(sa.select(ReceivedWebmention)).all()
+
+        assert len(webmentions) == 1
+
+        webmention = webmentions[0]
+
+        assert webmention.source == data["source"]
+        assert webmention.target == data["target"]
+        assert webmention.status == "received"
+        assert webmention.failure_reason is None
+
+        identifier = webmention.uuid
+
+    assert queued == [
+        identifier,
+        identifier,
+    ]
+
+
+def test_resending_resets_failure_state(
+    app: Flask,
+    client: FlaskClient,
+    views_module: ModuleType,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    monkeypatch.setattr(
+        views_module,
+        "verify_webmention",
+        lambda identifier: None,
+    )
+
+    source = "https://source.example/post"
+    target = "https://dennisfink.me/blog/example/"
+
+    with app.app_context():
+        existing = ReceivedWebmention(
+            uuid=uuid.uuid7(),
+            source=source,
+            target=target,
+            status="failed",
+            failure_reason="Previous failure",
+        )
+
+        db.session.add(existing)
+        db.session.commit()
+
+        identifier = existing.uuid
+
+    response = client.post(
+        "/endpoint",
+        data={
+            "source": source,
+            "target": target,
+        },
+    )
+
+    assert response.status_code == 201
+
+    with app.app_context():
+        webmention = db.session.get(
+            ReceivedWebmention,
+            identifier,
+        )
+
+        assert webmention is not None
+        assert webmention.status == "received"
+        assert webmention.failure_reason is None