divide docs in sections, provide Meta attributes inheritance, add tests for fastapi use wih mixins and concrete

docs/models/inheritance.md

@@ -0,0 +1,119 @@
+# Inheritance
+
+Out of various types of ORM models inheritance `ormar` currently supports two of them:
+
+* **Mixins**
+* **Concrete table inheritance** (with parents set to `abstract=True`)
+
+## Types of inheritance
+
+The short summary of different types of inheritance is:
+
+* **Mixins [SUPPORTED]** - don't even subclass `ormar.Model`, just define fields that are later used on several different models (like `created_date` and `updated_date` on each model), only actual models create tables but those fields from mixins are added
+* **Concrete table inheritance [SUPPORTED]** - means that parent is marked as abstract and each child has it's own table with columns from parent and own child columns, kind of similar to Mixins but parent also is a Model
+* **Single table inheritance [NOT SUPPORTED]** - means that only one table is created with fields that are combination/sum of the parent and all children models but child models use only subset of column in db (all parent and own ones, skipping the other children ones)
+* **Multi/ Joined table inheritance [NOT SUPPORTED]** - means that part of the columns is saved on parent model and part is saved on child model that are connected to each other by kind of one to one relation and under the hood you operate on two models at once
+* **Proxy models [NOT SUPPORTED]** - means that only parent has an actual table, children just add methods, modify settings etc.
+
+## Mixins
+
+To use Mixins just define a class that is not inheriting from an `ormar.Model` but is defining `ormar.Fields` as class variables.
+
+```python
+# a mixin defines the fields but is a normal python class 
+class AuditMixin:
+    created_by: str = ormar.String(max_length=100)
+    updated_by: str = ormar.String(max_length=100, default="Sam")
+
+class DateFieldsMixins:
+    created_date: datetime.datetime = ormar.DateTime(default=datetime.datetime.now)
+    updated_date: datetime.datetime = ormar.DateTime(default=datetime.datetime.now)
+
+
+# a models can inherit from one or more mixins
+class Category(ormar.Model, DateFieldsMixins, AuditMixin):
+    class Meta(ormar.ModelMeta):
+        tablename = "categories"
+        metadata = metadata
+        database = db
+
+    id: int = ormar.Integer(primary_key=True)
+    name: str = ormar.String(max_length=50, unique=True, index=True)
+    code: int = ormar.Integer()
+```
+
+!!!note
+    Note that Mixins are **not** models, so you still need to inherit from `ormar.Model` as well as define `Meta` class in the final model.
+
+A Category class above will have four additional fields: `created_date`, `updated_date`, `created_by` and `updated_by`.
+
+There will be only one table created for model Category, with `Category` class fields combined with all `Mixins` fields.
+
+Note that Mixin in class name is optional but is a good python practice.
+
+!!!warning
+    You cannot declare a field in a `Model` that is already defined in one of the `Mixins` you inherit from.
+    
+    So in example above `Category` cannot declare it's own `created_date` as this filed will be inherited from `DateFieldsMixins`.
+    
+    If you try to the `ModelDefinitionError` will be raised.
+
+## Concrete table inheritance
+
+In concept concrete table inheritance is very similar to Mixins, but uses actual `ormar.Models` as base classes.
+
+!!!warning
+    Note that base classes have `abstract=True` set in `Meta` class, if you try to inherit from non abstract marked class `ModelDefinitionError` will be raised.
+
+Since this abstract Model will never be initialized you can skip `metadata` and `database` in it's `Meta` definition.
+
+But if you provide it - it will be inherited, that way you do not have to provide `metadata` and `databases` in concrete class
+
+Note that you can always overwrite it in child/concrete class if you need to. 
+
+More over at least one of the classes in inheritance chain have to provide it - otherwise an error will be raised.
+
+```python
+# note that base classes have abstract=True
+# since this model will never be initialized you can skip metadata and database
+class AuditModel(ormar.Model):
+    class Meta:
+        abstract = True
+
+    created_by: str = ormar.String(max_length=100)
+    updated_by: str = ormar.String(max_length=100, default="Sam")
+
+# but if you provide it it will be inherited
+class DateFieldsModel(ormar.Model):
+    class Meta:
+        abstract = True
+        metadata = metadata
+        database = db
+
+    created_date: datetime.datetime = ormar.DateTime(default=datetime.datetime.now)
+    updated_date: datetime.datetime = ormar.DateTime(default=datetime.datetime.now)
+
+
+# that way you do not have to provide metadata and databases in concrete class
+class Category(DateFieldsModel, AuditModel):
+    class Meta(ormar.ModelMeta):
+        tablename = "categories"
+
+    id: int = ormar.Integer(primary_key=True)
+    name: str = ormar.String(max_length=50, unique=True, index=True)
+    code: int = ormar.Integer()
+
+```
+
+The list of inherited options/settings is as follows: `metadata`, `database` and `constraints`. 
+
+Also methods decorated with `@property_field` decorator will be inherited/recognized.
+
+Of course apart from that all fields from base classes are combined and created in the concrete table of the final Model.
+
+!!!warning
+    You cannot declare a field in a `Model` that is already defined in one of the `Mixins` you inherit from.
+    
+    So in example above `Category` cannot declare it's own `created_date` as this filed will be inherited from `DateFieldsMixins`.
+    
+    If you try to the `ModelDefinitionError` will be raised.

docs/relations/index.md

@@ -46,10 +46,42 @@ class Department(ormar.Model):
 !!!tip
     Reverse ForeignKey allows you to query the related models with [queryset-proxy][queryset-proxy].
     
+    It allows you to use `await department.courses.all()` to fetch data related only to specific department etc. 
+
 ##ManyToMany
 
 To define many-to-many relation use `ManyToMany` field.
 
+```python hl_lines="25-26"
+class Category(ormar.Model):
+    class Meta:
+        tablename = "categories"
+        database = database
+        metadata = metadata
+
+    id: int = ormar.Integer(primary_key=True)
+    name: str = ormar.String(max_length=40)
+
+# note: you need to specify through model
+class PostCategory(ormar.Model):
+    class Meta:
+        tablename = "posts_categories"
+        database = database
+        metadata = metadata
+
+class Post(ormar.Model):
+    class Meta:
+        tablename = "posts"
+        database = database
+        metadata = metadata
+
+    id: int = ormar.Integer(primary_key=True)
+    title: str = ormar.String(max_length=200)
+    categories: Optional[Union[Category, List[Category]]] = ormar.ManyToMany(
+        Category, through=PostCategory
+    )
+```
+
 
 !!!tip
     To read more about many-to-many relations visit [many-to-many][many-to-many] section
@@ -58,6 +90,8 @@ To define many-to-many relation use `ManyToMany` field.
 !!!tip
     ManyToMany allows you to query the related models with [queryset-proxy][queryset-proxy].
 
+    It allows you to use `await post.categories.all()` but also `await category.posts.all()` to fetch data related only to specific post, category etc.
+
 
 [foreign-keys]: ./foreign-key.md
 [many-to-many]: ./many-to-many.md

docs/releases.md

@@ -1,3 +1,7 @@
+# 0.7.3
+
+* Fix for setting fetching related model with UUDI pk, which is a string in raw (fix [#71][#71])
+
 # 0.7.2
 
 * Fix for overwriting related models with pk only in `Model.update() with fields passed as parameters` (fix [#70][#70])
@@ -189,3 +193,4 @@ Add queryset level methods
 [#60]: https://github.com/collerek/ormar/issues/60
 [#68]: https://github.com/collerek/ormar/issues/68
 [#70]: https://github.com/collerek/ormar/issues/70
+[#71]: https://github.com/collerek/ormar/issues/71

mkdocs.yml

@@ -5,6 +5,7 @@ nav:
   - Installation: install.md
   - Models:
     - Definition: models/index.md
+    - Inheritance: models/inheritance.md
     - Methods: models/methods.md
     - Migrations: models/migrations.md
     - Internals: models/internals.md
@@ -25,9 +26,9 @@ nav:
   - Release Notes: releases.md
 repo_name: collerek/ormar
 repo_url: https://github.com/collerek/ormar
-#google_analytics:
+google_analytics:
-#  - UA-72514911-3
+  - UA-72514911-3
-#  - auto
+  - auto
 theme:
   name: material
   highlightjs: true

ormar/__init__.py

@@ -44,7 +44,7 @@ class UndefinedType:  # pragma no cover
 
 Undefined = UndefinedType()
 
-__version__ = "0.7.2"
+__version__ = "0.7.4"
 __all__ = [
     "Integer",
     "BigInteger",

ormar/fields/foreign_key.py

@@ -1,3 +1,4 @@
+import uuid
 from typing import Any, List, Optional, TYPE_CHECKING, Type, Union
 
 import sqlalchemy
@@ -252,6 +253,8 @@ class ForeignKeyField(BaseField):
         :return: (if needed) registered Model
         :rtype: Model
         """
+        if cls.to.pk_type() == uuid.UUID and isinstance(value, str):
+            value = uuid.UUID(value)
         if not isinstance(value, cls.to.pk_type()):
             raise RelationshipInstanceError(
                 f"Relationship error - ForeignKey {cls.to.__name__} "

ormar/models/metaclass.py

@@ -1,6 +1,6 @@
 import logging
 import warnings
-from typing import Any, Dict, List, Optional, Set, TYPE_CHECKING, Tuple, Type, Union
+from typing import Any, Dict, List, Optional, Set, TYPE_CHECKING, Tuple, Type, Union, cast
 
 import databases
 import pydantic
@@ -540,6 +540,35 @@ def update_attrs_and_fields(
     model_fields.update(new_model_fields)
 
 
+def update_attrs_from_base_meta(
+        base_class: "Model",
+        attrs: Dict, ) -> None:
+    """
+    Updates Meta parameters in child from parent if needed.
+
+    :param base_class: one of the parent classes
+    :type base_class: Model or model parent class
+    :param attrs: new namespace for class being constructed
+    :type attrs: Dict
+    """
+    params_to_update = ["metadata", "database", "constraints", "property_fields"]
+    for param in params_to_update:
+        if hasattr(base_class.Meta, param):
+            if hasattr(attrs["Meta"], param):
+                curr_value = getattr(attrs["Meta"], param)
+                if isinstance(curr_value, list):
+                    curr_value.extend(getattr(base_class.Meta, param))
+                elif isinstance(curr_value, dict):  # pragma: no cover
+                    curr_value.update(getattr(base_class.Meta, param))
+                elif isinstance(curr_value, Set):
+                    curr_value.union(getattr(base_class.Meta, param))
+                else:
+                    # overwrite with child value if both set and its param / object
+                    setattr(attrs["Meta"], param, getattr(base_class.Meta, param)) # pragma: no cover
+            else:
+                setattr(attrs["Meta"], param, getattr(base_class.Meta, param))
+
+
 def extract_mixin_fields_from_dict(
         base_class: type,
         curr_class: type,
@@ -572,6 +601,7 @@ def extract_mixin_fields_from_dict(
     :rtype: Tuple[Dict, Dict]
     """
     if hasattr(base_class, "Meta"):
+        if attrs.get("Meta"):
             new_fields = set(base_class.Meta.model_fields.keys())  # type: ignore
             previous_fields = set({k for k, v in attrs.items() if isinstance(v, FieldInfo)})
             check_conflicting_fields(
@@ -586,7 +616,8 @@ def extract_mixin_fields_from_dict(
                     f"{curr_class.__name__} cannot inherit "
                     f"from non abstract class {base_class.__name__}"
                 )
-        model_fields.update(base_class.Meta.model_fields)  # type: ignore
+            update_attrs_from_base_meta(base_class=base_class, attrs=attrs)  # type: ignore
+            model_fields.update(base_class.Meta.model_fields)
         return attrs, model_fields
 
     key = "__annotations__"
@@ -649,12 +680,9 @@ class ModelMetaclass(pydantic.main.ModelMetaclass):
         attrs["Config"] = get_pydantic_base_orm_config()
         attrs["__name__"] = name
         attrs, model_fields = extract_annotations_and_default_vals(attrs)
-        for base in reversed(bases):
+        for ind, base in enumerate(reversed(bases)):
             attrs, model_fields = extract_mixin_fields_from_dict(
-                base_class=base,
+                base_class=base, curr_class=mcs, attrs=attrs, model_fields=model_fields
-                curr_class=mcs,
-                attrs=attrs,
-                model_fields=model_fields
             )
         new_model = super().__new__(  # type: ignore
             mcs, name, bases, attrs

ormar/models/newbasemodel.py

@@ -72,6 +72,8 @@ class NewBaseModel(
 
     # noinspection PyMissingConstructor
     def __init__(self, *args: Any, **kwargs: Any) -> None:  # type: ignore
+        if self.Meta.abstract:
+            raise ModelError(f"You cannot initialize abstract model {self.get_name()}")
         object.__setattr__(self, "_orm_id", uuid.uuid4().hex)
         object.__setattr__(self, "_orm_saved", False)
         object.__setattr__(self, "_pk_column", None)

tests/test_inheritance_concrete.py

@@ -9,6 +9,7 @@ from sqlalchemy import create_engine
 
 import ormar
 from ormar import ModelDefinitionError
+from ormar.exceptions import ModelError
 from tests.settings import DATABASE_URL
 
 metadata = sa.MetaData()
@@ -38,6 +39,8 @@ class DateFieldsModelNoSubclass(ormar.Model):
 class DateFieldsModel(ormar.Model):
     class Meta:
         abstract = True
+        metadata = metadata
+        database = db
 
     created_date: datetime.datetime = ormar.DateTime(default=datetime.datetime.now)
     updated_date: datetime.datetime = ormar.DateTime(default=datetime.datetime.now)
@@ -46,8 +49,6 @@ class DateFieldsModel(ormar.Model):
 class Category(DateFieldsModel, AuditModel):
     class Meta(ormar.ModelMeta):
         tablename = "categories"
-        metadata = metadata
-        database = db
 
     id: int = ormar.Integer(primary_key=True)
     name: str = ormar.String(max_length=50, unique=True, index=True)
@@ -56,9 +57,7 @@ class Category(DateFieldsModel, AuditModel):
 
 class Subject(DateFieldsModel):
     class Meta(ormar.ModelMeta):
-        tablename = "subjects"
+        pass
-        metadata = metadata
-        database = db
 
     id: int = ormar.Integer(primary_key=True)
     name: str = ormar.String(max_length=50, unique=True, index=True)
@@ -72,6 +71,11 @@ def create_test_database():
     metadata.drop_all(engine)
 
 
+def test_init_of_abstract_model():
+    with pytest.raises(ModelError):
+        DateFieldsModel()
+
+
 def test_field_redefining_raises_error():
     with pytest.raises(ModelDefinitionError):
         class WrongField(DateFieldsModel):  # pragma: no cover

tests/test_uuid_fks.py

@@ -0,0 +1,63 @@
+import uuid
+
+import databases
+import pytest
+import sqlalchemy
+from sqlalchemy import create_engine
+
+import ormar
+from tests.settings import DATABASE_URL
+
+metadata = sqlalchemy.MetaData()
+db = databases.Database(DATABASE_URL)
+
+
+class User(ormar.Model):
+    class Meta:
+        tablename = "user"
+        metadata = metadata
+        database = db
+
+    id: uuid.UUID = ormar.UUID(
+        primary_key=True, default=uuid.uuid4, uuid_format="string"
+    )
+    username = ormar.String(index=True, unique=True, null=False, max_length=255)
+    email = ormar.String(index=True, unique=True, nullable=False, max_length=255)
+    hashed_password = ormar.String(null=False, max_length=255)
+    is_active = ormar.Boolean(default=True, nullable=False)
+    is_superuser = ormar.Boolean(default=False, nullable=False)
+
+
+class Token(ormar.Model):
+    class Meta:
+        tablename = "token"
+        metadata = metadata
+        database = db
+
+    id = ormar.Integer(primary_key=True)
+    text = ormar.String(max_length=4, unique=True)
+    user = ormar.ForeignKey(User, related_name="tokens")
+    created_at = ormar.DateTime(server_default=sqlalchemy.func.now())
+
+
+@pytest.fixture(autouse=True, scope="module")
+def create_test_database():
+    engine = create_engine(DATABASE_URL)
+    metadata.create_all(engine)
+    yield
+    metadata.drop_all(engine)
+
+
+@pytest.mark.asyncio
+async def test_uuid_fk():
+    async with db:
+        async with db.transaction(force_rollback=True):
+            user = await User.objects.create(
+                username="User1",
+                email="email@example.com",
+                hashed_password="^$EDACVS(&A&Y@2131aa",
+                is_active=True,
+                is_superuser=False,
+            )
+            await Token.objects.create(text="AAAA", user=user)
+            await Token.objects.order_by("-created_at").all()