JSON encoder change via app (#2055)

sanic/app.py

@@ -84,6 +84,7 @@ def __init__(
         log_config: Optional[Dict[str, Any]] = None,
         configure_logging: bool = True,
         register: Optional[bool] = None,
+        dumps: Optional[Callable[..., str]] = None,
     ) -> None:
         super().__init__()
 
@@ -117,8 +118,6 @@ def __init__(
         self.websocket_tasks: Set[Future] = set()
         self.named_request_middleware: Dict[str, Deque[MiddlewareType]] = {}
         self.named_response_middleware: Dict[str, Deque[MiddlewareType]] = {}
-        # self.named_request_middleware: Dict[str, MiddlewareType] = {}
-        # self.named_response_middleware: Dict[str, MiddlewareType] = {}
         self._test_manager = None
         self._test_client = None
         self._asgi_client = None
@@ -133,6 +132,9 @@ def __init__(
 
         self.router.ctx.app = self
 
+        if dumps:
+            BaseHTTPResponse._dumps = dumps
+
     @property
     def loop(self):
         """

sanic/blueprint_group.py

@@ -61,7 +61,8 @@ def __init__(self, url_prefix=None, version=None, strict_slashes=None):
         Create a new Blueprint Group
 
         :param url_prefix: URL: to be prefixed before all the Blueprint Prefix
-        :param version: API Version for the blueprint group. This will be inherited by each of the Blueprint
+        :param version: API Version for the blueprint group. This will be
+            inherited by each of the Blueprint
         :param strict_slashes: URL Strict slash behavior indicator
         """
         self._blueprints = []
@@ -90,8 +91,8 @@ def blueprints(self) -> List["sanic.Blueprint"]:
     @property
     def version(self) -> Optional[Union[str, int, float]]:
         """
-        API Version for the Blueprint Group. This will be applied only in case if the Blueprint doesn't already have
-        a version specified
+        API Version for the Blueprint Group. This will be applied only in case
+        if the Blueprint doesn't already have a version specified
 
         :return: Version information
         """
@@ -162,7 +163,8 @@ def __len__(self) -> int:
 
     def _sanitize_blueprint(self, bp: "sanic.Blueprint") -> "sanic.Blueprint":
         """
-        Sanitize the Blueprint Entity to override the Version and strict slash behaviors as required.
+        Sanitize the Blueprint Entity to override the Version and strict slash
+        behaviors as required.
 
         :param bp: Sanic Blueprint entity Object
         :return: Modified Blueprint

sanic/blueprints.py

@@ -1,16 +1,16 @@
 from collections import defaultdict
-from typing import Dict, List, Optional, Iterable
+from typing import Dict, Iterable, List, Optional
 
 from sanic_routing.route import Route  # type: ignore
 
 from sanic.base import BaseSanic
 from sanic.blueprint_group import BlueprintGroup
+from sanic.models.futures import FutureRoute, FutureStatic
 from sanic.models.handler_types import (
     ListenerType,
     MiddlewareType,
     RouteHandler,
 )
-from sanic.models.futures import FutureRoute, FutureStatic
 
 
 class Blueprint(BaseSanic):
@@ -99,7 +99,8 @@ def group(*blueprints, url_prefix="", version=None, strict_slashes=None):
         :param blueprints: blueprints to be registered as a group
         :param url_prefix: URL route to be prepended to all sub-prefixes
         :param version: API Version to be used for Blueprint group
-        :param strict_slashes: Indicate strict slash termination behavior for URL
+        :param strict_slashes: Indicate strict slash termination behavior
+            for URL
         """
 
         def chain(nested) -> Iterable[Blueprint]:

sanic/models/futures.py

@@ -1,10 +1,10 @@
 from pathlib import PurePath
-from typing import NamedTuple, List, Union, Iterable, Optional
+from typing import Iterable, List, NamedTuple, Optional, Union
 
 from sanic.models.handler_types import (
+    ErrorMiddlewareType,
     ListenerType,
     MiddlewareType,
-    ErrorMiddlewareType,
 )
 
 

sanic/response.py

@@ -39,6 +39,8 @@ class BaseHTTPResponse:
     The base class for all HTTP Responses
     """
 
+    _dumps = json_dumps
+
     def __init__(self):
         self.asgi: bool = False
         self.body: Optional[bytes] = None
@@ -66,8 +68,8 @@ def cookies(self) -> CookieJar:
                 response.cookies["test"]["domain"] = ".yummy-yummy-cookie.com"
                 response.cookies["test"]["httponly"] = True
 
-        `See user guide
-        <https://sanicframework.org/guide/basics/cookies.html>`_
+        `See user guide re: cookies
+        <https://sanicframework.org/guide/basics/cookies.html>`__
 
         :return: the cookie jar
         :rtype: CookieJar
@@ -251,7 +253,7 @@ def json(
     status: int = 200,
     headers: Optional[Dict[str, str]] = None,
     content_type: str = "application/json",
-    dumps: Callable[..., str] = json_dumps,
+    dumps: Optional[Callable[..., str]] = None,
     **kwargs,
 ) -> HTTPResponse:
     """
@@ -262,6 +264,8 @@ def json(
     :param headers: Custom Headers.
     :param kwargs: Remaining arguments that are passed to the json encoder.
     """
+    if not dumps:
+        dumps = BaseHTTPResponse._dumps
     return HTTPResponse(
         dumps(body, **kwargs),
         headers=headers,

tests/test_blueprint_group.py

@@ -1,8 +1,8 @@
 from pytest import raises
 
 from sanic.app import Sanic
-from sanic.blueprints import Blueprint
 from sanic.blueprint_group import BlueprintGroup
+from sanic.blueprints import Blueprint
 from sanic.request import Request
 from sanic.response import HTTPResponse, text
 

tests/test_json_encoding.py

@@ -0,0 +1,92 @@
+import sys
+
+from dataclasses import asdict, dataclass
+from functools import partial
+from json import dumps as sdumps
+
+import pytest
+
+
+try:
+    from ujson import dumps as udumps
+
+    NO_UJSON = False
+    DEFAULT_DUMPS = udumps
+except ModuleNotFoundError:
+    NO_UJSON = True
+    DEFAULT_DUMPS = partial(sdumps, separators=(",", ":"))
+
+from sanic import Sanic
+from sanic.response import BaseHTTPResponse, json
+
+
+@dataclass
+class Foo:
+    bar: str
+
+    def __json__(self):
+        return udumps(asdict(self))
+
+
+@pytest.fixture
+def foo():
+    return Foo(bar="bar")
+
+
+@pytest.fixture
+def payload(foo):
+    return {"foo": foo}
+
+
+@pytest.fixture(autouse=True)
+def default_back_to_ujson():
+    yield
+    BaseHTTPResponse._dumps = DEFAULT_DUMPS
+
+
+def test_change_encoder():
+    Sanic("...", dumps=sdumps)
+    assert BaseHTTPResponse._dumps == sdumps
+
+
+def test_change_encoder_to_some_custom():
+    def my_custom_encoder():
+        return "foo"
+
+    Sanic("...", dumps=my_custom_encoder)
+    assert BaseHTTPResponse._dumps == my_custom_encoder
+
+
+@pytest.mark.skipif(NO_UJSON is True, reason="ujson not installed")
+def test_json_response_ujson(payload):
+    """ujson will look at __json__"""
+    response = json(payload)
+    assert response.body == b'{"foo":{"bar":"bar"}}'
+
+    with pytest.raises(
+        TypeError, match="Object of type Foo is not JSON serializable"
+    ):
+        json(payload, dumps=sdumps)
+
+    Sanic("...", dumps=sdumps)
+    with pytest.raises(
+        TypeError, match="Object of type Foo is not JSON serializable"
+    ):
+        json(payload)
+
+
+@pytest.mark.skipif(NO_UJSON is True, reason="ujson not installed")
+def test_json_response_json():
+    """One of the easiest ways to tell the difference is that ujson cannot
+    serialize over 64 bits"""
+    too_big_for_ujson = 111111111111111111111
+
+    with pytest.raises(OverflowError, match="int too big to convert"):
+        json(too_big_for_ujson)
+
+    response = json(too_big_for_ujson, dumps=sdumps)
+    assert sys.getsizeof(response.body) == 54
+
+    Sanic("...", dumps=sdumps)
+    response = json(too_big_for_ujson)
+    assert sys.getsizeof(response.body) == 54