Commit 103d4e1d authored by Markus Holtermann's avatar Markus Holtermann
Browse files

Fixed #26441 -- Added model Field.db_check() method 

Thanks Common Code for financing the work on this commit.
parent 8b1110dd

django/db/models/fields/__init__.py

+14 −6
Original line number Diff line number Diff line
@@ -594,9 +594,21 @@ class Field(RegisterLookupMixin): 
        self.run_validators(value)

        return value



    def db_check(self, connection):

        """

        Return the database column check constraint for this field, for the

        provided connection. Works the same way as db_type() for the case that

        get_internal_type() does not map to a preexisting model field.

        """

        data = DictWrapper(self.__dict__, connection.ops.quote_name, "qn_")

        try:

            return connection.data_type_check_constraints[self.get_internal_type()] % data

        except KeyError:

            return None



    def db_type(self, connection):

        """

        Returns the database column data type for this field, for the provided

        Return the database column data type for this field, for the provided

        connection.

        """

        # The default implementation of this method looks at the
@@ -634,12 +646,8 @@ class Field(RegisterLookupMixin): 
        values (type, checks).

        This will look at db_type(), allowing custom model fields to override it.

        """

        data = DictWrapper(self.__dict__, connection.ops.quote_name, "qn_")

        type_string = self.db_type(connection)

        try:

            check_string = connection.data_type_check_constraints[self.get_internal_type()] % data

        except KeyError:

            check_string = None

        check_string = self.db_check(connection)

        return {

            "type": type_string,

            "check": check_string,

django/db/models/fields/related.py

+7 −1
Original line number Diff line number Diff line
@@ -949,11 +949,14 @@ class ForeignKey(ForeignObject): 
        defaults.update(kwargs)

        return super(ForeignKey, self).formfield(**defaults)



    def db_check(self, connection):

        return []



    def db_type(self, connection):

        return self.target_field.rel_db_type(connection=connection)



    def db_parameters(self, connection):

        return {"type": self.db_type(connection), "check": []}

        return {"type": self.db_type(connection), "check": self.db_check(connection)}



    def convert_empty_strings(self, value, expression, connection, context):

        if (not value) and isinstance(value, six.string_types):
@@ -1614,6 +1617,9 @@ class ManyToManyField(RelatedField): 
            defaults['initial'] = [i._get_pk_val() for i in initial]

        return super(ManyToManyField, self).formfield(**defaults)



    def db_check(self, connection):

        return None



    def db_type(self, connection):

        # A ManyToManyField is not represented by a single column,

        # so return None.