Reading HTTP response from UART

Question

I'm using a Telit GE864-GPS modem, which runs a dialect of Python 1.5.2. The Python module has access to the modem using a buffered UART, which may still be receiving when reading starts. The following code makes sure the entire response is read, and return either the response body or '0' on timeout.

def receiveReponse ( ):
 # MOD.secCounter() provides the current time in seconds
 timeout = MOD.secCounter() + 10
 str = ""
 length = ""
 newlinepos = 0
 while ( MOD.secCounter() < timeout ):
 newlinepos = str.find("\n\r")
 if ( (newlinepos != -1) and not length ):
 newlinepos = newlinepos + 2
 pos = str.find("Content-Length:") + 15
 while ( str[pos] != '\n' ):
 length = "%s%s" % (length, str[pos])
 pos = pos + 1
 length = int(length) + newlinepos
 else:
 MOD.sleep(5)
 # MDM receive reads the current UART buffer
 str = str + MDM.receive(1)
 if ( length and len(str) >= length ):
 return str[newlinepos:(newlinepos+length)]
 return 0

The entire procedure seems rather overcomplicated. Am I missing some obvious simplifications?

Answer 1

This

 while ( str[pos] != '\n' ):
 length = "%s%s" % (length, str[pos])
 pos = pos + 1

could be just

 length = string.split(str[pos:], '\n')[0]

• Gareth Rees: Did string objects have a split method in 1.5.2? I think this wasn't added until 1.6. Before that you had to import string and then call string.split.
• Janne Karila: @GarethRees You are right; edited.