Add extension points to management command

src/drf_yasg/management/commands/generate_swagger.py

@@ -1,12 +1,11 @@
-import json
 import logging
 import os
-from collections import OrderedDict
-from importlib import import_module
 
 from django.contrib.auth import get_user_model
 from django.core.exceptions import ImproperlyConfigured
 from django.core.management.base import BaseCommand
+from django.utils.module_loading import import_string
+from rest_framework.settings import api_settings
 from rest_framework.test import APIRequestFactory, force_authenticate
 from rest_framework.views import APIView
 
@@ -15,15 +14,6 @@ from ...app_settings import swagger_settings
 from ...codecs import OpenAPICodecJson, OpenAPICodecYaml
 
 
-def import_class(import_string):
-    if not import_string:
-        return None
-
-    module_path, class_name = import_string.rsplit('.', 1)
-    module = import_module(module_path)
-    return getattr(module, class_name)
-
-
 class Command(BaseCommand):
     help = 'Write the Swagger schema to disk in JSON or YAML format.'
 
@@ -105,6 +95,17 @@ class Command(BaseCommand):
         request = APIView().initialize_request(request)
         return request
 
+    def get_schema_generator(self, generator_class_name, api_info, api_version, api_url):
+        generator_class = import_string(generator_class_name) or swagger_settings.DEFAULT_GENERATOR_CLASS
+        return generator_class(
+            info=api_info,
+            version=api_version,
+            url=api_url,
+        )
+
+    def get_schema(self, generator, request, public):
+        return generator.get_schema(request=request, public=public)
+
     def handle(self, output_file, overwrite, format, api_url, mock, api_version, user, private, generator_class_name,
                *args, **kwargs):
         # disable logs of WARNING and below
@@ -144,13 +145,8 @@ class Command(BaseCommand):
         if request and api_version:
             request.version = api_version
 
-        generator_class = import_class(generator_class_name) or swagger_settings.DEFAULT_GENERATOR_CLASS
+        generator = self.get_schema_generator(generator_class_name, info, api_version, api_url)
-        generator = generator_class(
+        schema = self.get_schema(generator, request, not private)
-            info=info,
-            version=api_version,
-            url=api_url,
-        )
-        schema = generator.get_schema(request=request, public=not private)
 
         if output_file == '-':
             self.write_schema(schema, self.stdout, format)