Python's sticky bag and subcontracting

Twisted's protocol.datareceived () can handle the raw data received, since it is original, it may be different from the "package" defined by the application layer, that is, sticky packets and sub-packages are difficult to avoid

Look at the code that handles the sticky pack:

#!/usr/bin/env python#coding=utf-8 import structdef mypack (data):     pack_format =  ' 2i%ds '     return struct.pack (Pack_format % len ( Data), 100,len (data), data)      #简单解码def  myunpack (data):     pack_ format =  ' 2i%ds '  %  (len (data)  - 2*4)     return  Struct.unpack (pack_format,data)   #解码 + handling Sticky pack def myunpack2 (data):     pack_format  =  ' 2i%ds '  %  (len (data)  - 2*4)      (VERSION,LENGTH,STR)   = struct.unpack (Pack_format,data)          if 0  <  (len (data)  - 2*4)-length):         #如果有粘包, the subsequent fields are Put in a string         pack_format =  ' 2i%ds%ds '  %  (length ,  (len (data)  - 2*4)-length)         return struct.unpack (pack_format,data)       else:        return  (VERSION,LENGTH,STR)    #测试if  __name__ ==  ' __main__ ':       import json     str = {' A ': 1111, ' B ': [], ' C ': ' Asfasdf '}    str =  json.dumps (str)           a = mypack (str)     print a    b = myunpack2 (a+a+a)      print b    while 3<len (b):         b = myunpack2 (b[3])         print b

Sub-package is relatively simple, that is, the last output of B to judge

If b[1] > len (b[2]): #分包了, the last data is placed in a temporary variable, waiting for the next data stream to process the pass

-----------------------------------------

Python's unpack function is not as powerful as PHP, and PHP's unpack can support matching patterns like * (any number)