fix: throw error when association proxy could not be converted

Signed-off-by: Erik Wrede <erikwrede2@gmail.com>

graphene_sqlalchemy/converter.py

@@ -91,6 +91,13 @@ def dynamic_type():
                 assoc_prop.value_attr,
                 **field_kwargs,
             ).get_type()
+        else:
+            raise TypeError(
+                "Unsupported association proxy target type: {} for prop {} on type {}. "
+                "Please disable the conversion of this field using an ORMField.".format(
+                    type(attr), assoc_prop, obj_type
+                )
+            )
         # else, not supported
 
     return graphene.Dynamic(dynamic_type)

graphene_sqlalchemy/tests/models.py

@@ -68,6 +68,18 @@ def __repr__(self):
         return "{} {}".format(self.first_name, self.last_name)
 
 
+class ProxiedReporter(Base):
+    __tablename__ = "reporters_error"
+    id = Column(Integer(), primary_key=True)
+    first_name = Column(String(30), doc="First name")
+    last_name = Column(String(30), doc="Last name")
+    reporter_id = Column(Integer(), ForeignKey("reporters.id"))
+    reporter = relationship("Reporter", uselist=False)
+
+    # This is a hybrid property, we don't support proxies on hybrids yet
+    composite_prop = association_proxy("reporter", "composite_prop")
+
+
 class Reporter(Base):
     __tablename__ = "reporters"
 

graphene_sqlalchemy/tests/test_converter.py

@@ -29,6 +29,7 @@
     Article,
     CompositeFullName,
     Pet,
+    ProxiedReporter,
     Reporter,
     ShoppingCart,
     ShoppingCartItem,
@@ -523,6 +524,25 @@ class Meta:
     assert dynamic_field.get_type().type.of_type == ArticleType
 
 
+def test_should_throw_error_association_proxy_unsupported_target():
+    class ProxiedReporterType(SQLAlchemyObjectType):
+        class Meta:
+            model = ProxiedReporter
+
+    field = convert_sqlalchemy_association_proxy(
+        ProxiedReporter,
+        ProxiedReporter.composite_prop,
+        ProxiedReporterType,
+        get_global_registry(),
+        default_connection_field_factory,
+        True,
+        mock_resolver,
+    )
+
+    with pytest.raises(TypeError):
+        field.get_type()
+
+
 def test_should_postgresql_uuid_convert():
     assert get_field(postgresql.UUID()).type == graphene.UUID