From 3d9b5d7084d52e749553ca79206ed7060f963f9d Mon Sep 17 00:00:00 2001
From: Miguel Grinberg <miguel.grinberg@gmail.com>
Date: Sat, 4 May 2019 21:07:42 +0000
Subject: [PATCH] optional asyncio support

---
 microdot_async.py | 148 ++++++++++++++++++++++++++++++++++++++++++++++
 tox.ini           |   2 +-
 2 files changed, 149 insertions(+), 1 deletion(-)
 create mode 100644 microdot_async.py

diff --git a/microdot_async.py b/microdot_async.py
new file mode 100644
index 0000000..03cbe5f
--- /dev/null
+++ b/microdot_async.py
@@ -0,0 +1,148 @@
+try:
+    import uasyncio as asyncio
+except ImportError:
+    import asyncio
+from microdot import Microdot as BaseMicrodot
+from microdot import print_exception
+from microdot import Request as BaseRequest
+from microdot import Response as BaseResponse
+
+
+class Request(BaseRequest):
+    @staticmethod
+    async def create(stream, client_addr):
+        # request line
+        line = (await stream.readline()).strip().decode()
+        method, url, http_version = line.split()
+        http_version = http_version.split('/', 1)[1]
+
+        # headers
+        headers = {}
+        content_length = 0
+        while True:
+            line = (await stream.readline()).strip().decode()
+            if line == '':
+                break
+            header, value = line.split(':', 1)
+            value = value.strip()
+            headers[header] = value
+            if header == 'Content-Length':
+                content_length = int(value)
+
+        # body
+        body = await stream.read(content_length) \
+            if content_length else b''
+
+        return Request(client_addr, method, url, http_version, headers, body)
+
+
+class Response(BaseResponse):
+    async def write(self, stream):
+        self.complete()
+
+        # status code
+        await stream.awrite('HTTP/1.0 {status_code} {reason}\r\n'.format(
+            status_code=self.status_code,
+            reason='OK' if self.status_code == 200 else 'N/A').encode())
+
+        # headers
+        for header, value in self.headers.items():
+            values = value if isinstance(value, list) else [value]
+            for value in values:
+                await stream.awrite('{header}: {value}\r\n'.format(
+                    header=header, value=value).encode())
+        await stream.awrite(b'\r\n')
+
+        # body
+        if self.body:
+            await stream.awrite(self.body)
+
+
+class Microdot(BaseMicrodot):
+    def run(self, host='0.0.0.0', port=5000, debug=False):
+        async def serve(reader, writer):
+            req = await Request.create(reader,
+                                       writer.get_extra_info('peername'))
+            res = await self.dispatch_request(req)
+            if debug:  # pragma: no cover
+                print('{method} {path} {status_code}'.format(
+                    method=req.method, path=req.path,
+                    status_code=res.status_code))
+
+            if not hasattr(writer, 'awrite'):
+                class AWriter:
+                    def __init__(self, writer):
+                        self.writer = writer
+
+                    async def awrite(self, data):
+                        self.writer.write(data)
+                        await self.writer.drain()
+
+                    async def aclose(self):
+                        self.writer.close()
+
+                writer = AWriter(writer)
+            await res.write(writer)
+            await writer.aclose()
+
+        if debug:  # pragma: no cover
+            print('Listening on {host}:{port}...'.format(host=host, port=port))
+        loop = asyncio.get_event_loop()
+        loop.run_until_complete(asyncio.start_server(serve, host, port))
+        loop.run_forever()
+        loop.close()
+
+    async def dispatch_request(self, req):
+        f = self.find_route(req)
+        try:
+            res = None
+            if f:
+                for handler in self.before_request_handlers:
+                    res = await self._invoke_handler(handler, req)
+                    if res:
+                        break
+                if res is None:
+                    res = await self._invoke_handler(f, req, **req.url_args)
+                if isinstance(res, tuple):
+                    res = Response(*res)
+                elif not isinstance(res, Response):
+                    res = Response(res)
+                for handler in self.after_request_handlers:
+                    res = await self._invoke_handler(handler, req, res) or res
+            elif 404 in self.error_handlers:
+                res = self._invoke_handler(self.error_handlers[404], req)
+            else:
+                res = 'Not found', 404
+        except Exception as exc:
+            print_exception(exc)
+            res = None
+            if exc.__class__ in self.error_handlers:
+                try:
+                    res = self._invoke_handler(
+                        self.error_handlers[exc.__class__], req, exc)
+                except Exception as exc2:  # pragma: no cover
+                    print_exception(exc2)
+            if res is None:
+                if 500 in self.error_handlers:
+                    res = await self._invoke_handler(self.error_handlers[500],
+                                                     req)
+                else:
+                    res = 'Internal server error', 500
+        if isinstance(res, tuple):
+            res = Response(*res)
+        elif not isinstance(res, Response):
+            res = Response(res)
+        return res
+
+    async def _invoke_handler(self, f_or_coro, *args, **kwargs):
+        r = f_or_coro(*args, **kwargs)
+        try:
+            r = await r
+        except TypeError:
+            # not a coroutine
+            pass
+        return r
+
+
+redirect = Response.redirect
+send_file = Response.send_file
diff --git a/tox.ini b/tox.ini
index ec30624..21504c7 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,7 +4,7 @@ skip_missing_interpreters=True
 
 [testenv]
 commands=
-    coverage run --branch --include="microdot.py" -m unittest tests
+    coverage run --branch --include="microdot*.py" -m unittest tests
     coverage report --show-missing
     coverage erase
 deps=coverage