initial commit

pypistats/database.py

@@ -0,0 +1,62 @@
+"""Database classes and models."""
+from pypistats.extensions import db
+
+
+Column = db.Column
+basestring = (str, bytes)
+
+
+class CRUDMixin(object):
+    """Mixin that adds convenience methods for CRUD operations."""
+
+    @classmethod
+    def create(cls, **kwargs):
+        """Create a new record and save it the database."""
+        instance = cls(**kwargs)
+        return instance.save()
+
+    def update(self, commit=True, **kwargs):
+        """Update specific fields of a record."""
+        for attr, value in kwargs.items():
+            setattr(self, attr, value)
+        return commit and self.save() or self
+
+    def save(self, commit=True):
+        """Save the record."""
+        db.session.add(self)
+        if commit:
+            db.session.commit()
+        return self
+
+    def delete(self, commit=True):
+        """Remove the record from the database."""
+        db.session.delete(self)
+        return commit and db.session.commit()
+
+
+class Model(CRUDMixin, db.Model):
+    """Base model class that includes CRUD convenience methods."""
+
+    __abstract__ = True
+
+
+class SurrogatePK(object):
+    """A mixin that adds a surrogate integer 'primary key' column.
+
+    Adds a surrogate integer 'primary key' columnnamed ``id`` to any
+    declarative-mapped class.
+    """
+
+    __table_args__ = {'extend_existing': True}
+
+    id = Column(db.Integer, primary_key=True)
+
+    @classmethod
+    def get_by_id(cls, record_id):
+        """Get record by ID."""
+        if any(
+                (isinstance(record_id, basestring) and record_id.isdigit(),
+                 isinstance(record_id, (int, float))),
+        ):
+            return cls.query.get(int(record_id))
+        return None