use declarative_base for all ORM models

This rewrites the entire model base as declarative models.
This allows us to more easily customize overlay fields
in tables and is more common.

This effort also brought some DB violations to light which
this commit addresses.

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

aurweb/models/package_dependency.py

@@ -1,17 +1,40 @@
+from sqlalchemy import Column, ForeignKey, Integer
 from sqlalchemy.exc import IntegrityError
-from sqlalchemy.orm import mapper
+from sqlalchemy.orm import backref, relationship
 
-from aurweb.db import make_relationship
-from aurweb.models.dependency_type import DependencyType
-from aurweb.models.package import Package
-from aurweb.schema import PackageDepends
+import aurweb.models.package
+
+from aurweb.models import dependency_type
+from aurweb.models.declarative import Base
 
 
-class PackageDependency:
-    def __init__(self, Package: Package = None,
-                 DependencyType: DependencyType = None,
-                 DepName: str = None, DepDesc: str = None,
-                 DepCondition: str = None, DepArch: str = None):
+class PackageDependency(Base):
+    __tablename__ = "PackageDepends"
+
+    PackageID = Column(
+        Integer, ForeignKey("Packages.ID", ondelete="CASCADE"),
+        nullable=False)
+    Package = relationship(
+        "Package", backref=backref("package_dependencies", lazy="dynamic"),
+        foreign_keys=[PackageID], lazy="select")
+
+    DepTypeID = Column(
+        Integer, ForeignKey("DependencyTypes.ID", ondelete="NO ACTION"),
+        nullable=False)
+    DependencyType = relationship(
+        "DependencyType",
+        backref=backref("package_dependencies", lazy="dynamic"),
+        foreign_keys=[DepTypeID], lazy="select")
+
+    __mapper_args__ = {"primary_key": [PackageID, DepTypeID]}
+
+    def __init__(self,
+                 Package: aurweb.models.package.Package = None,
+                 DependencyType: dependency_type.DependencyType = None,
+                 DepName: str = None,
+                 DepDesc: str = None,
+                 DepCondition: str = None,
+                 DepArch: str = None):
         self.Package = Package
         if not self.Package:
             raise IntegrityError(
@@ -36,15 +59,3 @@ class PackageDependency:
         self.DepDesc = DepDesc
         self.DepCondition = DepCondition
         self.DepArch = DepArch
-
-
-properties = {
-    "Package": make_relationship(Package, PackageDepends.c.PackageID,
-                                 "package_dependencies"),
-    "DependencyType": make_relationship(DependencyType,
-                                        PackageDepends.c.DepTypeID,
-                                        "package_dependencies")
-}
-
-mapper(PackageDependency, PackageDepends, properties=properties,
-       primary_key=[PackageDepends.c.PackageID, PackageDepends.c.DepTypeID])