Add ASGI adapter

tests/test_asgi.py

@@ -0,0 +1,236 @@
+import asyncio
+import io
+import os
+import stat
+import tempfile
+
+import pytest
+
+from whitenoise.asgi import convert_asgi_headers, convert_wsgi_headers, read_file, receive_request, serve_static_file, \
+    AsgiWhiteNoise
+from whitenoise.responders import StaticFile
+
+from .test_whitenoise import application as whitenoise_application, files
+
+
+@pytest.fixture()
+def loop():
+    return asyncio.get_event_loop()
+
+
+class MockStat:
+    def __init__(self, st_mode, st_size, st_mtime):
+        self.st_mode = st_mode
+        self.st_size = st_size
+        self.st_mtime = st_mtime
+
+
+@pytest.fixture()
+def static_file_sample():
+    content = b"01234567890123456789"
+    modification_time = "Sun, 09 Sep 2001 01:46:40 GMT"
+    modification_epoch = 1000000000
+    temporary_file = tempfile.NamedTemporaryFile(suffix=".js", delete=False)
+    try:
+        temporary_file.write(content)
+        temporary_file.close()
+        stat_cache = {
+            temporary_file.name: MockStat(stat.S_IFREG, len(content), modification_epoch)
+        }
+        static_file = StaticFile(temporary_file.name, [], stat_cache=stat_cache)
+        yield {
+            "static_file": static_file,
+            "content": content,
+            "content_length": len(content),
+            "modification_time": modification_time,
+        }
+    finally:
+        os.unlink(temporary_file.name)
+
+
+@pytest.fixture(params=["GET", "HEAD"])
+def method(request):
+    return request.param
+
+
+@pytest.fixture(params=[10, 20])
+def block_size(request):
+    return request.param
+
+
+@pytest.fixture()
+def file_not_found():
+    async def application(scope, receive, send):
+        if scope["type"] != "http":
+            raise RuntimeError()
+        await receive()
+        await send({"type": "http.response.start", "status": 404})
+        await send({"type": "http.response.body", "body": b"Not found"})
+
+    return application
+
+
+@pytest.fixture()
+def websocket():
+    async def application(scope, receive, send):
+        if scope["type"] != "websocket":
+            raise RuntimeError()
+        await receive()
+        await send({"type": "websocket.accept"})
+        await send({"type": "websocket.close"})
+
+    return application
+
+
+class Receiver:
+    def __init__(self):
+        self.events = [{"type": "http.request"}]
+
+    async def __call__(self):
+        return self.events.pop(0)
+
+
+class Sender:
+    def __init__(self):
+        self.events = []
+
+    async def __call__(self, event):
+        self.events.append(event)
+
+
+@pytest.fixture()
+def receive():
+    return Receiver()
+
+
+@pytest.fixture()
+def send():
+    return Sender()
+
+
+def test_asgiwhitenoise(loop, receive, send, method, whitenoise_application, files):
+    asgi_whitenoise = AsgiWhiteNoise(whitenoise_application, None)
+    scope = {
+        "type": "http",
+        "path": "/" + files.js_path,
+        "headers": [],
+        "method": method,
+    }
+    loop.run_until_complete(asgi_whitenoise(scope, receive, send))
+    assert receive.events == []
+    assert send.events[0]["status"] == 200
+    if method == "GET":
+        assert send.events[1]["body"] == files.js_content
+
+
+def test_asgiwhitenoise_not_found(loop, receive, send, whitenoise_application, file_not_found):
+    asgi_whitenoise = AsgiWhiteNoise(whitenoise_application, file_not_found)
+    scope = {
+        "type": "http",
+        "path": "/static/foo.js",
+        "headers": [],
+        "method": "GET",
+    }
+    loop.run_until_complete(asgi_whitenoise(scope, receive, send))
+    assert receive.events == []
+    assert send.events == [
+        {"type": "http.response.start", "status": 404},
+        {"type": "http.response.body", "body": b"Not found"},
+    ]
+
+
+def test_asgiwhitenoise_not_http(loop, receive, send, whitenoise_application, websocket):
+    asgi_whitenoise = AsgiWhiteNoise(whitenoise_application, websocket)
+    receive.events = [{"type": "websocket.connect"}]
+    scope = {
+        "type": "websocket",
+        "path": "/endpoint",
+        "headers": [],
+        "method": "GET",
+    }
+    loop.run_until_complete(asgi_whitenoise(scope, receive, send))
+    assert receive.events == []
+    assert send.events == [
+        {"type": "websocket.accept"},
+        {"type": "websocket.close"},
+    ]
+
+
+def test_serve_static_file(loop, send, method, block_size, static_file_sample):
+    loop.run_until_complete(serve_static_file(send, static_file_sample["static_file"], method, {}, block_size))
+    expected_events = [
+        {
+            "type": "http.response.start",
+            "status": 200,
+            "headers": [
+                (b"last-modified", static_file_sample["modification_time"].encode()),
+                (b"etag", static_file_sample["static_file"].etag.encode()),
+                (b"content-length", str(static_file_sample["content_length"]).encode()),
+            ],
+        }]
+    if method == "GET":
+        for start in range(0, static_file_sample["content_length"], block_size):
+            expected_events.append({
+                "type": "http.response.body",
+                "body": static_file_sample["content"][start:start + block_size],
+                "more_body": True,
+            })
+    expected_events.append({"type": "http.response.body"})
+    assert send.events == expected_events
+
+
+def test_receive_request(loop, receive):
+    loop.run_until_complete(receive_request(receive))
+    assert receive.events == []
+
+
+def test_receive_request_with_more_body(loop, receive):
+    receive.events = [
+        {"type": "http.request", "more_body": True, "body": b"content"},
+        {"type": "http.request", "more_body": True, "body": b"more content"},
+        {"type": "http.request"},
+    ]
+    loop.run_until_complete(receive_request(receive))
+    assert receive.events == []
+
+
+def test_receive_request_with_invalid_event(loop, receive):
+    receive.events = [{"type": "http.weirdstuff"}]
+    with pytest.raises(RuntimeError):
+        loop.run_until_complete(receive_request(receive))
+
+
+def test_read_file():
+    content = io.BytesIO(b"0123456789")
+    content.seek(4)
+    blocks = list(read_file(content, content_length=5, block_size=2))
+    assert blocks == [b"45", b"67", b"8"]
+
+
+def test_read_too_short_file():
+    content = io.BytesIO(b"0123456789")
+    content.seek(4)
+    with pytest.raises(RuntimeError):
+        list(read_file(content, content_length=11, block_size=2))
+
+
+def test_convert_asgi_headers():
+    wsgi_headers = convert_asgi_headers([
+        (b"accept-encoding", b"gzip,br"),
+        (b"range", b"bytes=10-100"),
+    ])
+    assert wsgi_headers == {
+        "HTTP_ACCEPT_ENCODING": "gzip,br",
+        "HTTP_RANGE": "bytes=10-100",
+    }
+
+
+def test_convert_wsgi_headers():
+    wsgi_headers = convert_wsgi_headers([
+        ("Content-Length", "1234"),
+        ("ETag", "ada"),
+    ])
+    assert wsgi_headers == [
+        (b"content-length", b"1234"),
+        (b"etag", b"ada"),
+    ]

whitenoise/asgi.py

@@ -0,0 +1,74 @@
+class AsgiWhiteNoise:
+    # This is the same block size as wsgiref.FileWrapper
+    BLOCK_SIZE = 8192
+
+    def __init__(self, whitenoise, application):
+        self.whitenoise = whitenoise
+        self.application = application
+
+    async def __call__(self, scope, receive, send):
+        static_file = None
+        if scope["type"] == "http":
+            if self.whitenoise.autorefresh:
+                static_file = self.whitenoise.find_file(scope["path"])
+            else:
+                static_file = self.whitenoise.files.get(scope["path"])
+        if static_file is None:
+            await self.application(scope, receive, send)
+        else:
+            await receive_request(receive)
+            request_headers = convert_asgi_headers(scope["headers"])
+            await serve_static_file(
+                send, static_file, scope["method"], request_headers, self.BLOCK_SIZE
+            )
+
+
+async def serve_static_file(send, static_file, method, request_headers, block_size):
+    response = static_file.get_response(method, request_headers)
+    try:
+        await send({
+            "type": "http.response.start",
+            "status": response.status.value,
+            "headers": convert_wsgi_headers(response.headers),
+        })
+        if response.file:
+            # We need to only read content-length bytes instead of the whole file,
+            # the difference is important when serving range requests.
+            content_length = int(dict(response.headers)["Content-Length"])
+            for block in read_file(response.file, content_length, block_size):
+                await send({"type": "http.response.body", "body": block, "more_body": True})
+        await send({"type": "http.response.body"})
+    finally:
+        if response.file:
+            response.file.close()
+
+
+async def receive_request(receive):
+    more_body = True
+    while more_body:
+        event = await receive()
+        if event["type"] != "http.request":
+            raise RuntimeError(
+                "Unexpected ASGI event {!r}, expected {!r}".format(event["type"], "http.request")
+            )
+        more_body = event.get("more_body", False)
+
+
+def read_file(file_handle, content_length, block_size):
+    bytes_left = content_length
+    while bytes_left > 0:
+        data = file_handle.read(min(block_size, bytes_left))
+        if data == b"":
+            raise RuntimeError("Premature end of file, expected {} more bytes".format(bytes_left))
+        bytes_left -= len(data)
+        yield data
+
+
+def convert_asgi_headers(headers):
+    return {
+        "HTTP_" + name.decode().upper().replace('-', '_'): value.decode()
+        for name, value in headers}
+
+
+def convert_wsgi_headers(headers):
+    return [(key.lower().encode(), value.encode()) for key, value in headers]