json socket utility

README.md

@@ -1,31 +1,14 @@
-jsonsocket
-==========
+json socket utility
+===================
 
-This is a small Python library for sending data over sockets.
+This is a simple python utility for sending json data when using sockets.
 
-It allows sending lists, dictionaries, strings, etc. It can handle very large data (I've tested it with 10GB of data). Any JSON-serializable data is accepted.
+It allows sending lists, dictionaries, strings, etc. It can handle very large data (It has been tested with 10GB of data). Any JSON-serializable data is accepted.
 
-Examples:
+these two functions don't require re-write/over-writing the socket library and are python3 compatible.
 
-```python
-from jsonsocket import Client, Server
+get a taste for using sockets here: http://tutorialspoint.com/python/python_networking.htm
 
-host = 'localhost'
-port = '8000'
+an example of working with json data over sockets can be found here: http://github.com/chris-rose-one/battleship
 
-# Client code:
-client = Client()
-client.connect(host, port).send({'some_list': [123, 456]})
-response = client.recv()
-# response now is {'data': {'some_list': [123, 456]}}
-client.close()
-
-
-# Server code:
-server = Server(host, port)
-server.accept()
-data = server.recv()
-# data now is: {'some_list': [123, 456]}
-server.send({'data': data}).close()
-
-```
+thanks @mdebbar this code has been quite helpful

json_utils.py

@@ -0,0 +1,45 @@
+import json
+
+def send_json(socket, data):
+	try:
+		serialized = json.dumps(data)
+	except (TypeError, ValueError) as e:
+		raise Exception('You can only send JSON-serializable data')
+	# send the length of the serialized data first
+	socket.send(('%d\n').encode() % len(serialized))
+	# send the serialized data
+	socket.sendall(serialized.encode())
+
+def receive_json(socket):
+	# read the length of the data, letter by letter until we reach EOL
+	length_str = ''
+	char = socket.recv(1).decode()
+	if char == '':
+		return char
+	while char != '\n':
+		length_str += char
+		char = socket.recv(1).decode()
+	total = int(length_str)
+	print(total)
+	# use a memoryview to receive the data chunk by chunk efficiently
+	view = memoryview(bytearray(total))
+	next_offset = 0
+	while total - next_offset > 0:
+		recv_size = socket.recv_into(view[next_offset:], total - next_offset)
+		next_offset += recv_size
+	try:
+		hexdump(view)
+		deserialized = json.loads(view.tobytes().decode())
+	except (TypeError, ValueError) as e:
+		raise Exception('Data received was not in JSON format')
+	return deserialized
+
+def hexdump(src, length=16):
+	result = []
+	digits = 4 if isinstance(src, unicode) else 2
+	for i in xrange(0, len(src), length):
+		s = src[i:i+length]
+		hexa = b' '.join(["%0*X" % (digits, ord(x))  for x in s])
+		text = b''.join([x if 0x20 <= ord(x) < 0x7F else b'.'  for x in s])
+		result.append( b"%04X   %-*s   %s" % (i, length*(digits + 1), hexa, text) )
+	print b'\n'.join(result)