add large binary field, tests and docs

ormar/__init__.py

@@ -53,6 +53,7 @@ from ormar.fields import (
     ForeignKeyField,
     Integer,
     JSON,
+    LargeBinary,
     ManyToMany,
     ManyToManyField,
     String,
@@ -124,4 +125,5 @@ __all__ = [
     "EncryptBackends",
     "ENCODERS_MAP",
     "DECODERS_MAP",
+    "LargeBinary",
 ]

ormar/fields/__init__.py

@@ -16,6 +16,7 @@ from ormar.fields.model_fields import (
     Float,
     Integer,
     JSON,
+    LargeBinary,
     String,
     Text,
     Time,
@@ -50,4 +51,5 @@ __all__ = [
     "EncryptBackend",
     "DECODERS_MAP",
     "ENCODERS_MAP",
+    "LargeBinary",
 ]

ormar/fields/model_fields.py

@@ -415,6 +415,53 @@ class JSON(ModelFieldFactory, pydantic.Json):
         return sqlalchemy.JSON()
 
 
+class LargeBinary(ModelFieldFactory, bytes):
+    """
+    LargeBinary field factory that construct Field classes and populated their values.
+    """
+
+    _type = bytes
+
+    def __new__(  # type: ignore # noqa CFQ002
+        cls, *, max_length: int = None, **kwargs: Any
+    ) -> BaseField:  # type: ignore
+        kwargs = {
+            **kwargs,
+            **{
+                k: v
+                for k, v in locals().items()
+                if k not in ["cls", "__class__", "kwargs"]
+            },
+        }
+        return super().__new__(cls, **kwargs)
+
+    @classmethod
+    def get_column_type(cls, **kwargs: Any) -> Any:
+        """
+        Return proper type of db column for given field type.
+        Accepts required and optional parameters that each column type accepts.
+
+        :param kwargs: key, value pairs of sqlalchemy options
+        :type kwargs: Any
+        :return: initialized column with proper options
+        :rtype: sqlalchemy Column
+        """
+        return sqlalchemy.LargeBinary(length=kwargs.get("max_length"))
+
+    @classmethod
+    def validate(cls, **kwargs: Any) -> None:
+        """
+        Used to validate if all required parameters on a given field type are set.
+        :param kwargs: all params passed during construction
+        :type kwargs: Any
+        """
+        max_length = kwargs.get("max_length", None)
+        if max_length is None or max_length <= 0:
+            raise ModelDefinitionError(
+                "Parameter max_length is required for field LargeBinary"
+            )
+
+
 class BigInteger(Integer, int):
     """
     BigInteger field factory that construct Field classes and populated their values.

ormar/models/helpers/validation.py

@@ -73,6 +73,8 @@ def convert_choices_if_needed(  # noqa: CCR001
             else value
         )
         choices = [round(float(o), precision) for o in choices]
+    elif field.__type__ == bytes:
+        value = value if isinstance(value, bytes) else value.encode("utf-8")
 
     return value, choices