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, 89 insertions, 0 deletions

diff --git a/webmentions_ssg/models.py b/webmentions_ssg/models.py
new file mode 100644
index 0000000..8c378aa
--- /dev/null
+++ b/webmentions_ssg/models.py
@@ -0,0 +1,89 @@
+import uuid
+from datetime import datetime, timezone
+from typing import Optional
+
+from flask_login import UserMixin
+from sqlalchemy import DateTime, String, Text, UniqueConstraint, Uuid
+from sqlalchemy.orm import Mapped, mapped_column
+from werkzeug.security import check_password_hash, generate_password_hash
+
+from . import Base
+
+
+class User(UserMixin, Base):
+    __tablename__ = "users"
+
+    id: Mapped[int] = mapped_column(primary_key=True)
+    username: Mapped[str] = mapped_column(
+        String(64),
+        index=True,
+        unique=True,
+    )
+    password_hash: Mapped[Optional[str]] = mapped_column(String(256))
+
+    def __repr__(self):
+        return f"<User {self.username}>"
+
+    def set_password(self, password):
+        self.password_hash = generate_password_hash(password)
+
+    def check_password(self, password):
+        return check_password_hash(
+            self.password_hash,
+            password,
+        )
+
+
+class ReceivedWebmention(Base):
+    __tablename__ = "received_webmentions"
+
+    uuid: Mapped[uuid.UUID] = mapped_column(
+        Uuid(as_uuid=True),
+        primary_key=True,
+    )
+
+    source: Mapped[str] = mapped_column(
+        Text(),
+        nullable=False,
+    )
+    target: Mapped[str] = mapped_column(
+        Text(),
+        nullable=False,
+    )
+
+    status: Mapped[str] = mapped_column(
+        Text(),
+        nullable=False,
+        default="received",
+    )
+    failure_reason: Mapped[str | None] = mapped_column(
+        Text(),
+        nullable=True,
+        default=None,
+    )
+
+    updated_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True),
+        default=lambda: datetime.now(timezone.utc),
+        onupdate=lambda: datetime.now(timezone.utc),
+        nullable=False,
+    )
+
+    __table_args__ = (
+        UniqueConstraint(
+            "source",
+            "target",
+            name="uq_webmention_source_target",
+        ),
+    )
+
+    @property
+    def verified(self) -> bool:
+        return self.status == "verified"
+
+    @property
+    def created_at(self) -> datetime:
+        return datetime.fromtimestamp(
+            self.uuid.time / 1000,
+            tz=timezone.utc,
+        )