setup relations

playground.py

@@ -0,0 +1,66 @@
+from src.masoniteorm.models import Model
+
+class User(Model):
+    __table__ = "tbl_users"
+    __primary_key__ = "user_id"
+
+    @property
+    def company(self):
+        related = Company()
+
+        related.owner = self
+        return HasOne(related, "company_id", "company_id")(self)
+
+
+class Company(Model):
+    __table__ = "tbl_companies"
+    __primary_key__ = "company_id"
+
+    def __call__(self):
+        foreign_key_value = self.__dict__['related'].owner.__attributes__.get(self.__dict__['related'].foreign_key)
+        builder = self.builder.where(self.__dict__['related'].local_key, foreign_key_value)
+        return builder
+
+class BaseRelationship:
+    def init(self, model_class, local_key=None, foreign_key=None):
+        self.model_class = model_class
+        self.local_key = local_key
+        self.foreign_key = foreign_key
+
+    def __call__(self, owner):
+        """Create and return the relationship query."""
+        # self.set_keys(owner)
+        related_model = self.model_class()
+        return self.apply_query(related_model.builder, owner)
+
+class HasOne(BaseRelationship):
+    """Belongs To Relationship Class."""
+
+    def __init__(self, model_class, foreign_key=None, local_key=None):
+        self.model_class = model_class
+        self.foreign_key = foreign_key
+        self.local_key = local_key
+
+    def __call__(self, owner):
+        """Fetch the related record when invoked."""
+        related_model = self.model_class
+        # print("related model", related_model)
+        related_model.owner = self
+        foreign_key_value = owner.__attributes__.get(self.foreign_key)
+        if not foreign_key_value:
+            return None
+        builder = related_model.builder.where(self.local_key, foreign_key_value)
+        result = builder.first()
+        self.owner = owner
+        result.__dict__['related'] = self
+        return result
+
+
+# Usage has one
+user = User.find(667)
+
+# fetches record on related company record
+print(user.company.company_name)  # Output: Company name
+
+# user.company() part returns a query builder so we can fetch related queries on the fly
+print(user.company().to_sql())  # Output: select * from tbl_companies where tbl_companies.company_id = 373849