Add JsonResponse (#6174)

docs/topics/request-response.rst

@@ -1357,3 +1357,13 @@ XmlResponse objects
     line.  See :attr:`TextResponse.encoding`.
 
 .. _bug in lxml: https://bugs.launchpad.net/lxml/+bug/1665241
+
+JsonResponse objects
+--------------------
+
+.. class:: JsonResponse(url[, ...])
+
+    The :class:`JsonResponse` class is a subclass of :class:`TextResponse` 
+    that is used when the response has a `JSON MIME type 
+    <https://mimesniff.spec.whatwg.org/#json-mime-type>`_ in its `Content-Type` 
+    header.

scrapy/http/__init__.py

@@ -12,5 +12,6 @@ from scrapy.http.request.json_request import JsonRequest
 from scrapy.http.request.rpc import XmlRpcRequest
 from scrapy.http.response import Response
 from scrapy.http.response.html import HtmlResponse
+from scrapy.http.response.json import JsonResponse
 from scrapy.http.response.text import TextResponse
 from scrapy.http.response.xml import XmlResponse

scrapy/http/response/json.py

@@ -0,0 +1,12 @@
+"""
+This module implements the JsonResponse class that is used when the response
+has a JSON MIME type in its Content-Type header.
+
+See documentation in docs/topics/request-response.rst
+"""
+
+from scrapy.http.response.text import TextResponse
+
+
+class JsonResponse(TextResponse):
+    pass

scrapy/responsetypes.py

@@ -21,9 +21,9 @@ class ResponseTypes:
         "application/xhtml+xml": "scrapy.http.HtmlResponse",
         "application/vnd.wap.xhtml+xml": "scrapy.http.HtmlResponse",
         "application/xml": "scrapy.http.XmlResponse",
-        "application/json": "scrapy.http.TextResponse",
-        "application/x-json": "scrapy.http.TextResponse",
-        "application/json-amazonui-streaming": "scrapy.http.TextResponse",
+        "application/json": "scrapy.http.JsonResponse",
+        "application/x-json": "scrapy.http.JsonResponse",
+        "application/json-amazonui-streaming": "scrapy.http.JsonResponse",
         "application/javascript": "scrapy.http.TextResponse",
         "application/x-javascript": "scrapy.http.TextResponse",
         "text/xml": "scrapy.http.XmlResponse",

tests/test_responsetypes.py

@@ -1,6 +1,13 @@
 import unittest
 
-from scrapy.http import Headers, HtmlResponse, Response, TextResponse, XmlResponse
+from scrapy.http import (
+    Headers,
+    HtmlResponse,
+    JsonResponse,
+    Response,
+    TextResponse,
+    XmlResponse,
+)
 from scrapy.responsetypes import responsetypes
 
 
@@ -40,8 +47,9 @@ class ResponseTypesTest(unittest.TestCase):
             ("application/vnd.wap.xhtml+xml; charset=utf-8", HtmlResponse),
             ("application/xml; charset=UTF-8", XmlResponse),
             ("application/octet-stream", Response),
-            ("application/x-json; encoding=UTF8;charset=UTF-8", TextResponse),
-            ("application/json-amazonui-streaming;charset=UTF-8", TextResponse),
+            ("application/json; encoding=UTF8;charset=UTF-8", JsonResponse),
+            ("application/x-json; encoding=UTF8;charset=UTF-8", JsonResponse),
+            ("application/json-amazonui-streaming;charset=UTF-8", JsonResponse),
             (b"application/x-download; filename=\x80dummy.txt", Response),
         ]
         for source, cls in mappings: