basic request streaming support with flow control

README.rst

@@ -1,7 +1,44 @@
 Sanic
 =====
 
-|Join the chat at https://gitter.im/sanic-python/Lobby| |Build Status| |AppVeyor Build Status| |Documentation| |Codecov| |PyPI| |PyPI version| |Code style black|
+.. start-badges
+
+.. list-table::
+    :stub-columns: 1
+
+    * - Build
+      - | |Build Status| |AppVeyor Build Status| |Codecov|
+    * - Docs
+      - |Documentation|
+    * - Package
+      - | |PyPI| |PyPI version| |Wheel| |Supported implementations| |Code style black|
+    * - Support
+      - |Join the chat at https://gitter.im/sanic-python/Lobby|
+
+.. |Join the chat at https://gitter.im/sanic-python/Lobby| image:: https://badges.gitter.im/sanic-python/Lobby.svg
+   :target: https://gitter.im/sanic-python/Lobby?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge
+.. |Codecov| image:: https://codecov.io/gh/huge-success/sanic/branch/master/graph/badge.svg
+    :target: https://codecov.io/gh/huge-success/sanic
+.. |Build Status| image:: https://travis-ci.org/huge-success/sanic.svg?branch=master
+   :target: https://travis-ci.org/huge-success/sanic
+.. |AppVeyor Build Status| image:: https://ci.appveyor.com/api/projects/status/d8pt3ids0ynexi8c/branch/master?svg=true
+   :target: https://ci.appveyor.com/project/huge-success/sanic
+.. |Documentation| image:: https://readthedocs.org/projects/sanic/badge/?version=latest
+   :target: http://sanic.readthedocs.io/en/latest/?badge=latest
+.. |PyPI| image:: https://img.shields.io/pypi/v/sanic.svg
+   :target: https://pypi.python.org/pypi/sanic/
+.. |PyPI version| image:: https://img.shields.io/pypi/pyversions/sanic.svg
+   :target: https://pypi.python.org/pypi/sanic/
+.. |Code style black| image:: https://img.shields.io/badge/code%20style-black-000000.svg
+    :target: https://github.com/ambv/black
+.. |Wheel| image:: https://img.shields.io/pypi/wheel/sanic.svg
+    :alt: PyPI Wheel
+    :target: https://pypi.python.org/pypi/sanic
+.. |Supported implementations| image:: https://img.shields.io/pypi/implementation/sanic.svg
+    :alt: Supported implementations
+    :target: https://pypi.python.org/pypi/sanic
+
+.. end-badges
 
 Sanic is a Flask-like Python 3.5+ web server that's written to go fast.  It's based on the work done by the amazing folks at magicstack, and was inspired by `this article <https://magic.io/blog/uvloop-blazing-fast-python-networking/>`_.
 
@@ -45,22 +82,6 @@ Documentation
 
 `Documentation on Readthedocs <http://sanic.readthedocs.io/>`_.
 
-.. |Join the chat at https://gitter.im/sanic-python/Lobby| image:: https://badges.gitter.im/sanic-python/Lobby.svg
-   :target: https://gitter.im/sanic-python/Lobby?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge
-.. |Codecov| image:: https://codecov.io/gh/huge-success/sanic/branch/master/graph/badge.svg
-    :target: https://codecov.io/gh/huge-success/sanic
-.. |Build Status| image:: https://travis-ci.org/huge-success/sanic.svg?branch=master
-   :target: https://travis-ci.org/huge-success/sanic
-.. |AppVeyor Build Status| image:: https://ci.appveyor.com/api/projects/status/d8pt3ids0ynexi8c/branch/master?svg=true
-   :target: https://ci.appveyor.com/project/huge-success/sanic
-.. |Documentation| image:: https://readthedocs.org/projects/sanic/badge/?version=latest
-   :target: http://sanic.readthedocs.io/en/latest/?badge=latest
-.. |PyPI| image:: https://img.shields.io/pypi/v/sanic.svg
-   :target: https://pypi.python.org/pypi/sanic/
-.. |PyPI version| image:: https://img.shields.io/pypi/pyversions/sanic.svg
-   :target: https://pypi.python.org/pypi/sanic/
-.. |Code style black| image:: https://img.shields.io/badge/code%20style-black-000000.svg
-    :target: https://github.com/ambv/black
 
 Questions and Discussion
 ------------------------

docs/sanic/config.md

@@ -88,6 +88,7 @@ Out of the box there are just a few predefined values which can be overwritten w
     | Variable                  | Default   | Description                                            |
     | ------------------------- | --------- | ------------------------------------------------------ |
     | REQUEST_MAX_SIZE          | 100000000 | How big a request may be (bytes)                       |
+    | REQUEST_BUFFER_QUEUE_SIZE | 100       | Request streaming buffer queue size                    |
     | REQUEST_TIMEOUT           | 60        | How long a request can take to arrive (sec)            |
     | RESPONSE_TIMEOUT          | 60        | How long a response can take to process (sec)          |
     | KEEP_ALIVE                | True      | Disables keep-alive when False                         |

docs/sanic/streaming.md

@@ -2,7 +2,7 @@
 
 ## Request Streaming
 
-Sanic allows you to get request data by stream, as below. When the request ends, `request.stream.get()` returns `None`. Only post, put and patch decorator have stream argument.
+Sanic allows you to get request data by stream, as below. When the request ends, `await request.stream.read()` returns `None`. Only post, put and patch decorator have stream argument.
 
 ```python
 from sanic import Sanic
@@ -22,7 +22,7 @@ class SimpleView(HTTPMethodView):
     async def post(self, request):
         result = ''
         while True:
-            body = await request.stream.get()
+            body = await request.stream.read()
             if body is None:
                 break
             result += body.decode('utf-8')
@@ -33,7 +33,7 @@ class SimpleView(HTTPMethodView):
 async def handler(request):
     async def streaming(response):
         while True:
-            body = await request.stream.get()
+            body = await request.stream.read()
             if body is None:
                 break
             body = body.decode('utf-8').replace('1', 'A')
@@ -45,7 +45,7 @@ async def handler(request):
 async def bp_handler(request):
     result = ''
     while True:
-        body = await request.stream.get()
+        body = await request.stream.read()
         if body is None:
             break
         result += body.decode('utf-8').replace('1', 'A')
@@ -55,7 +55,7 @@ async def bp_handler(request):
 async def post_handler(request):
     result = ''
     while True:
-        body = await request.stream.get()
+        body = await request.stream.read()
         if body is None:
             break
         result += body.decode('utf-8')

sanic/app.py

@@ -1071,6 +1071,7 @@ def _helper(
             "response_timeout": self.config.RESPONSE_TIMEOUT,
             "keep_alive_timeout": self.config.KEEP_ALIVE_TIMEOUT,
             "request_max_size": self.config.REQUEST_MAX_SIZE,
+            "request_buffer_queue_size": self.config.REQUEST_BUFFER_QUEUE_SIZE,
             "keep_alive": self.config.KEEP_ALIVE,
             "loop": loop,
             "register_sys_signals": register_sys_signals,

sanic/config.py

@@ -32,6 +32,7 @@ def __init__(self, defaults=None, load_env=True, keep_alive=True):
  ▀▀▄▄▀
 """
         self.REQUEST_MAX_SIZE = 100000000  # 100 megabytes
+        self.REQUEST_BUFFER_QUEUE_SIZE = 100
         self.REQUEST_TIMEOUT = 60  # 60 seconds
         self.RESPONSE_TIMEOUT = 60  # 60 seconds
         self.KEEP_ALIVE = keep_alive

sanic/request.py

@@ -1,3 +1,4 @@
+import asyncio
 import json
 import sys
 
@@ -47,6 +48,23 @@ def getlist(self, name, default=None):
         return super().get(name, default)
 
 
+class StreamBuffer:
+    def __init__(self, buffer_size=100):
+        self._queue = asyncio.Queue(buffer_size)
+
+    async def read(self):
+        """ Stop reading when gets None """
+        payload = await self._queue.get()
+        self._queue.task_done()
+        return payload
+
+    async def put(self, payload):
+        await self._queue.put(payload)
+
+    def is_full(self):
+        return self._queue.full()
+
+
 class Request(dict):
     """Properties of an HTTP request such as URL, headers, etc."""
 

sanic/server.py

@@ -22,7 +22,7 @@
     ServiceUnavailable,
 )
 from sanic.log import access_logger, logger
-from sanic.request import Request
+from sanic.request import Request, StreamBuffer
 from sanic.response import HTTPResponse
 
 
@@ -59,6 +59,7 @@ class HttpProtocol(asyncio.Protocol):
         "response_timeout",
         "keep_alive_timeout",
         "request_max_size",
+        "request_buffer_queue_size",
         "request_class",
         "is_request_stream",
         "router",
@@ -82,11 +83,12 @@ def __init__(
         request_handler,
         error_handler,
         signal=Signal(),
-        connections=set(),
+        connections=None,
         request_timeout=60,
         response_timeout=60,
         keep_alive_timeout=5,
         request_max_size=None,
+        request_buffer_queue_size=100,
         request_class=None,
         access_log=True,
         keep_alive=True,
@@ -105,10 +107,11 @@ def __init__(
         self.router = router
         self.signal = signal
         self.access_log = access_log
-        self.connections = connections
+        self.connections = connections or set()
         self.request_handler = request_handler
         self.error_handler = error_handler
         self.request_timeout = request_timeout
+        self.request_buffer_queue_size = request_buffer_queue_size
         self.response_timeout = response_timeout
         self.keep_alive_timeout = keep_alive_timeout
         self.request_max_size = request_max_size
@@ -291,17 +294,27 @@ def on_headers_complete(self):
                 self.request
             )
             if self._is_stream_handler:
-                self.request.stream = asyncio.Queue()
+                self.request.stream = StreamBuffer(
+                    self.request_buffer_queue_size
+                )
                 self.execute_request_handler()
 
     def on_body(self, body):
         if self.is_request_stream and self._is_stream_handler:
             self._request_stream_task = self.loop.create_task(
-                self.request.stream.put(body)
+                self.body_append(body)
             )
             return
         self.request.body_push(body)
 
+    async def body_append(self, body):
+        if self.request.stream.is_full():
+            self.transport.pause_reading()
+            await self.request.stream.put(body)
+            self.transport.resume_reading()
+        else:
+            await self.request.stream.put(body)
+
     def on_message_complete(self):
         # Entire request (headers and whole body) is received.
         # We can cancel and remove the request timeout handler now.
@@ -568,6 +581,7 @@ def serve(
     ssl=None,
     sock=None,
     request_max_size=None,
+    request_buffer_queue_size=100,
     reuse_port=False,
     loop=None,
     protocol=HttpProtocol,
@@ -628,6 +642,7 @@ def serve(
                                   outgoing bytes, the low-water limit is a
                                   quarter of the high-water limit.
     :param is_request_stream: disable/enable Request.stream
+    :param request_buffer_queue_size: streaming request buffer queue size
     :param router: Router object
     :param graceful_shutdown_timeout: How long take to Force close non-idle
                                       connection