add PackageComment SQLAlchemy ORM model

Signed-off-by: Kevin Morris <kevr@0cost.org>

aurweb/models/package_comment.py

@@ -0,0 +1,72 @@
+from sqlalchemy import Column, ForeignKey, Integer
+from sqlalchemy.exc import IntegrityError
+from sqlalchemy.orm import backref, relationship
+
+import aurweb.models.package_base
+import aurweb.models.user
+
+from aurweb.models.declarative import Base
+
+
+class PackageComment(Base):
+    __tablename__ = "PackageComments"
+
+    ID = Column(Integer, primary_key=True)
+
+    PackageBaseID = Column(
+        Integer, ForeignKey("PackageBases.ID", ondelete="CASCADE"),
+        nullable=False)
+    PackageBase = relationship(
+        "PackageBase", backref=backref("comments", lazy="dynamic"),
+        foreign_keys=[PackageBaseID])
+
+    UsersID = Column(Integer, ForeignKey("Users.ID", ondelete="SET NULL"))
+    User = relationship(
+        "User", backref=backref("package_comments", lazy="dynamic"),
+        foreign_keys=[UsersID])
+
+    EditedUsersID = Column(
+        Integer, ForeignKey("Users.ID", ondelete="SET NULL"))
+    Editor = relationship(
+        "User", backref=backref("edited_comments", lazy="dynamic"),
+        foreign_keys=[EditedUsersID])
+
+    DelUsersID = Column(
+        Integer, ForeignKey("Users.ID", ondelete="SET NULL"))
+    Deleter = relationship(
+        "User", backref=backref("deleted_comments", lazy="dynamic"),
+        foreign_keys=[DelUsersID])
+
+    __mapper_args__ = {"primary_key": [ID]}
+
+    def __init__(self,
+                 PackageBase: aurweb.models.package_base.PackageBase = None,
+                 User: aurweb.models.user.User = None,
+                 **kwargs):
+        super().__init__(**kwargs)
+
+        self.PackageBase = PackageBase
+        if not self.PackageBase:
+            raise IntegrityError(
+                statement="Foreign key PackageBaseID cannot be null.",
+                orig="PackageComments.PackageBaseID",
+                params=("NULL"))
+
+        self.User = User
+        if not self.User:
+            raise IntegrityError(
+                statement="Foreign key UsersID cannot be null.",
+                orig="PackageComments.UsersID",
+                params=("NULL"))
+
+        if self.Comments is None:
+            raise IntegrityError(
+                statement="Column Comments cannot be null.",
+                orig="PackageComments.Comments",
+                params=("NULL"))
+
+        if self.RenderedComment is None:
+            raise IntegrityError(
+                statement="Column RenderedComment cannot be null.",
+                orig="PackageComments.RenderedComment",
+                params=("NULL"))