Improve aiohttp usage for ddi (readchunk and timeout)

Replaces read(chunk_size) with readchunk which reads as much as it can.
This is the better approach than to choose a chunk_size that works well
under all circumstances (HTTP, HTTPS).

Also, sets the timeouts properly. Before the context helper didn't do
anything since the requests would timeout after 5 minutes anyway.
Now, the timeouts are respected as expected.

Signed-off-by: Livio Bieri <livio@livio.li>

rauc_hawkbit/ddi/client.py

@@ -6,6 +6,7 @@
 import hashlib
 import logging
 
+from aiohttp.client import ClientTimeout
 from datetime import datetime
 from enum import Enum
 
@@ -163,17 +164,17 @@ async def get_resource(self, api_path, query_params={}, **kwargs):
                     **kwargs))
 
         self.logger.debug('GET {}'.format(url))
-        with aiohttp.Timeout(self.timeout):
-            async with self.session.get(url, headers=get_headers,
-                                        params=query_params) as resp:
-                await self.check_http_status(resp)
-                json = await resp.json()
-                self.logger.debug(json)
-                return json
+        async with self.session.get(url, headers=get_headers,
+                                    params=query_params,
+                                    timeout=ClientTimeout(self.timeout)) as resp:
+            await self.check_http_status(resp)
+            json = await resp.json()
+            self.logger.debug(json)
+            return json
 
     async def get_binary_resource(self, api_path, dl_location,
                                   mime='application/octet-stream',
-                                  chunk_size=512, timeout=3600, **kwargs):
+                                  timeout=3600, **kwargs):
         """
         Helper method for binary HTTP GET API requests.
 
@@ -185,7 +186,6 @@ async def get_binary_resource(self, api_path, dl_location,
         Keyword Args:
             mime: mimetype of content to retrieve
                   (default: 'application/octet-stream')
-            chunk_size: size of chunk to retrieve
             kwargs: Other keyword args used for replacing items in the API path
 
         Returns:
@@ -196,11 +196,10 @@ async def get_binary_resource(self, api_path, dl_location,
                     tenant=self.tenant,
                     controllerId=self.controller_id,
                     **kwargs))
-        return await self.get_binary(url, dl_location, mime, chunk_size,
-                                     timeout=timeout)
+        return await self.get_binary(url, dl_location, mime, timeout=timeout)
 
     async def get_binary(self, url, dl_location,
-                         mime='application/octet-stream', chunk_size=512,
+                         mime='application/octet-stream',
                          timeout=3600):
         """
         Actual download method with checksum checking.
@@ -211,9 +210,8 @@ async def get_binary(self, url, dl_location,
         Keyword Args:
             mime: mimetype of content to retrieve
                   (default: 'application/octet-stream')
-            chunk_size: size of chunk to retrieve
             timeout: download timeout
-                     (default: 3600)
+                  (default: 3600)
 
         Returns:
             MD5 hash of downloaded content
@@ -225,17 +223,25 @@ async def get_binary(self, url, dl_location,
         hash_md5 = hashlib.md5()
 
         self.logger.debug('GET binary {}'.format(url))
-        with aiohttp.Timeout(timeout, loop=self.session.loop):
-            async with self.session.get(url, headers=get_bin_headers) as resp:
-                await self.check_http_status(resp)
-                with open(dl_location, 'wb') as fd:
-                    while True:
-                        with aiohttp.Timeout(60):
-                            chunk = await resp.content.read(chunk_size)
-                            if not chunk:
-                                break
-                            fd.write(chunk)
-                            hash_md5.update(chunk)
+
+        # session timeout & single socket read timeout
+        timeout = ClientTimeout(timeout, sock_read=60)
+
+        async with self.session.get(url, headers=get_bin_headers,
+                                    timeout=timeout) as resp:
+
+            await self.check_http_status(resp)
+            with open(dl_location, 'wb') as fd:
+                while True:
+                    chunk, _ = await resp.content.readchunk()
+
+                    # we are EOF
+                    if not chunk:
+                        break
+
+                    fd.write(chunk)
+                    hash_md5.update(chunk)
+
         return hash_md5.hexdigest()
 
     async def post_resource(self, api_path, data, **kwargs):
@@ -259,10 +265,11 @@ async def post_resource(self, api_path, data, **kwargs):
                     controllerId=self.controller_id,
                     **kwargs))
         self.logger.debug('POST {}'.format(url))
-        with aiohttp.Timeout(self.timeout):
-            async with self.session.post(url, headers=post_headers,
-                                         data=json.dumps(data)) as resp:
-                await self.check_http_status(resp)
+
+        async with self.session.post(url, headers=post_headers,
+                                     data=json.dumps(data),
+                                     timeout=ClientTimeout(self.timeout)) as resp:
+            await self.check_http_status(resp)
 
     async def put_resource(self, api_path, data, **kwargs):
         """
@@ -285,10 +292,11 @@ async def put_resource(self, api_path, data, **kwargs):
                     **kwargs))
         self.logger.debug('PUT {}'.format(url))
         self.logger.debug(json.dumps(data))
-        with aiohttp.Timeout(self.timeout):
-            async with self.session.put(url, headers=put_headers,
-                                        data=json.dumps(data)) as resp:
-                await self.check_http_status(resp)
+
+        async with self.session.put(url, headers=put_headers,
+                                    data=json.dumps(data),
+                                    timeout=ClientTimeout(self.timeout)) as resp:
+            await self.check_http_status(resp)
 
     async def check_http_status(self, resp):
         """Log API error message."""