Receive data from socket in a more reliable way

socket.recv() may return partial answer, so it must be called in loop.

opcua/binary_client.py

@@ -7,6 +7,7 @@ import socket
 from threading import Thread, Condition, Lock
 
 import opcua.uaprotocol as ua
+import opcua.utils as utils
 
 class Buffer(object):
     """
@@ -107,7 +108,7 @@ class BinaryClient(object):
 
     def _receive_body(self, size):
         self.logger.debug("reading body of message (%s bytes)", size)
-        data = self._socket.recv(size)
+        data = utils.recv_all(self._socket, size)
         if size != len(data):
             raise Exception("Error, did not received expected number of bytes, got {}, asked for {}".format(len(data), size))
         #return io.BytesIO(data)

opcua/uaprotocol_hand.py

@@ -4,6 +4,7 @@ import logging
 
 import opcua.uaprotocol_auto as auto
 import opcua.uatypes as uatypes 
+import opcua.utils as utils
 
 logger = logging.getLogger(__name__)
 
@@ -11,7 +12,7 @@ class SocketClosedException(Exception):
     pass
 
 def get_bytes_from_sock(sock, size):
-    data = sock.recv(size)
+    data = utils.recv_all(sock, size)
     if len(data) < size: #socket has closed!
         raise SocketClosedException("Server socket has closed")
     return io.BytesIO(data)

opcua/utils.py

+import socket
+
+def recv_all(socket, size):
+    """
+    Receive up to size bytes from socket
+    """
+    data = b''
+    while size > 0:
+        chunk = socket.recv(size)
+        if not chunk:
+            break
+        data += chunk
+        size -= len(chunk)
+    return data