Force descriptions to be str objects

Fixes #159

src/drf_yasg/codecs.py

@@ -5,6 +5,7 @@ import json
 from collections import OrderedDict
 
 from coreapi.compat import force_bytes
+from django.utils.safestring import SafeData, SafeText
 from ruamel import yaml
 
 from . import openapi

src/drf_yasg/generators.py

@@ -5,7 +5,6 @@ from collections import OrderedDict, defaultdict
 
 import uritemplate
 from coreapi.compat import urlparse
-from django.utils.encoding import force_text
 from rest_framework import versioning
 from rest_framework.compat import URLPattern, URLResolver, get_original_route
 from rest_framework.schemas.generators import EndpointEnumerator as _EndpointEnumerator
@@ -18,7 +17,7 @@ from .app_settings import swagger_settings
 from .errors import SwaggerGenerationError
 from .inspectors.field import get_basic_type_info, get_queryset_field
 from .openapi import ReferenceResolver
-from .utils import get_consumes, get_produces
+from .utils import force_real_str, get_consumes, get_produces
 
 logger = logging.getLogger(__name__)
 
@@ -435,7 +434,7 @@ class OpenAPISchemaGenerator(object):
                 attrs['pattern'] = getattr(view_cls, 'lookup_value_regex', attrs.get('pattern', None))
 
             if model_field and getattr(model_field, 'help_text', False):
-                description = force_text(model_field.help_text)
+                description = model_field.help_text
             elif model_field and getattr(model_field, 'primary_key', False):
                 description = get_pk_description(model, model_field)
             else:
@@ -443,7 +442,7 @@ class OpenAPISchemaGenerator(object):
 
             field = openapi.Parameter(
                 name=variable,
-                description=description,
+                description=force_real_str(description),
                 required=True,
                 in_=openapi.IN_PATH,
                 **attrs

src/drf_yasg/inspectors/base.py

@@ -1,12 +1,11 @@
 import inspect
 import logging
 
-from django.utils.encoding import force_text
 from rest_framework import serializers
 from rest_framework.utils import encoders, json
 
 from .. import openapi
-from ..utils import decimal_as_float, is_list_view
+from ..utils import decimal_as_float, force_real_str, is_list_view
 
 #: Sentinel value that inspectors must return to signal that they do not know how to handle an object
 NotHandled = object()
@@ -196,9 +195,9 @@ class FieldInspector(BaseInspector):
         """
         assert swagger_object_type in (openapi.Schema, openapi.Parameter, openapi.Items)
         assert not isinstance(field, openapi.SwaggerDict), "passed field is already a SwaggerDict object"
-        title = force_text(field.label) if field.label else None
+        title = force_real_str(field.label) if field.label else None
         title = title if swagger_object_type == openapi.Schema else None  # only Schema has title
-        description = force_text(field.help_text) if field.help_text else None
+        description = force_real_str(field.help_text) if field.help_text else None
         description = description if swagger_object_type != openapi.Items else None  # Items has no description either
 
         def SwaggerType(existing_object=None, **instance_kwargs):

src/drf_yasg/inspectors/query.py

@@ -3,6 +3,8 @@ from collections import OrderedDict
 import coreschema
 from rest_framework.pagination import CursorPagination, LimitOffsetPagination, PageNumberPagination
 
+from drf_yasg.utils import force_real_str
+
 from .. import openapi
 from .base import FilterInspector, PaginatorInspector
 
@@ -48,7 +50,7 @@ class CoreAPICompatInspector(PaginatorInspector, FilterInspector):
             in_=location_to_in[field.location],
             type=coreapi_types.get(type(field.schema), openapi.TYPE_STRING),
             required=field.required,
-            description=field.schema.description if field.schema else None,
+            description=force_real_str(field.schema.description) if field.schema else None,
         )
 
 

src/drf_yasg/inspectors/view.py

@@ -8,7 +8,7 @@ from rest_framework.status import is_success
 from .. import openapi
 from ..errors import SwaggerGenerationError
 from ..utils import (
-    force_serializer_instance, get_consumes, get_produces, guess_response_status, is_list_view, no_body,
+    force_real_str, force_serializer_instance, get_consumes, get_produces, guess_response_status, is_list_view, no_body,
     param_list_to_odict
 )
 from .base import ViewInspector
@@ -42,7 +42,7 @@ class SwaggerAutoSchema(ViewInspector):
 
         return openapi.Operation(
             operation_id=operation_id,
-            description=description,
+            description=force_real_str(description),
             responses=responses,
             parameters=parameters,
             consumes=consumes,
@@ -246,7 +246,7 @@ class SwaggerAutoSchema(ViewInspector):
         for sc, serializer in response_serializers.items():
             if isinstance(serializer, str):
                 response = openapi.Response(
-                    description=serializer
+                    description=force_real_str(serializer)
                 )
             elif not serializer:
                 continue

src/drf_yasg/utils.py

@@ -3,6 +3,7 @@ import logging
 from collections import OrderedDict
 
 from django.db import models
+from django.utils.encoding import force_text
 from rest_framework import serializers, status
 from rest_framework.mixins import DestroyModelMixin, RetrieveModelMixin, UpdateModelMixin
 from rest_framework.request import is_form_media_type
@@ -319,3 +320,17 @@ def get_serializer_ref_name(serializer):
         if ref_name.endswith('Serializer'):
             ref_name = ref_name[:-len('Serializer')]
     return ref_name
+
+
+def force_real_str(s, encoding='utf-8', strings_only=False, errors='strict'):
+    """
+    Force `s` into a ``str`` instance.
+
+    Fix for https://github.com/axnsan12/drf-yasg/issues/159
+    """
+    if s is not None:
+        s = force_text(s, encoding, strings_only, errors)
+        if type(s) != str:
+            s = '' + s
+
+    return s