http chunked 理解

https://imququ.com/post/transfer-encoding-header-in-http.html

#! /usr/bin/python
#coding:utf8

import socket
import signal
import errno

from time import sleep

def sig_handler(signo, frame):
    print "get signo ", signo
    global runFlg
    runFlg = False
    global listeningFd
    listeningFd.shutdown(socket.SHUT_RD)

def http_response_with_content_length(sock):
    """ 有長度沒有 close """
    sock.send('HTTP/1.1 200 OK\r\n')
    sock.send('Content-Length: 12\r\n')
    sock.send('\r\n')
    sock.send('Hello World!')

def http_response_with_close(sock):
    """" 沒有長度有 close """
    sock.send('HTTP/1.1 200 OK\r\n')
    sock.send('\r\n')
    sock.send('Hello World!')
    sock.close()

def http_response_chunked(sock):
    """" 沒有長度，沒有 close """
    sock.send('HTTP/1.1 200 OK\r\n')
    sock.send('Transfer-Encoding: chunked\r\n')
    sock.send('\r\n')

    # 第一個 chunk
    sock.send('a\r\n')
    sock.send('1234567890\r\n')

    # 第二個 chunk
    sock.send('5\r\n')
    sock.send('12345\r\n')

    # 第三個 chunk，也是最後一個
    sock.send('0\r\n')
    sock.send('\r\n')

def http_response(sock):
    """" 沒有長度，沒有 close """
    sock.send('HTTP/1.1 200 OK\r\n')
    sock.send('\r\n')
    sock.send('Hello World!')

signal.signal(signal.SIGINT, sig_handler)

HOST = "127.0.0.1"
PORT = 37001

listeningFd = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
listeningFd.bind((HOST, PORT))
listeningFd.listen(2)

print "HttpServer Started"

runFlg = True
while runFlg:
    try:
        connectedFd, addr = listeningFd.accept()
    except socket.error as e:
        if e.errno == errno.EINT:
            print "get a except EINTR"
        else:
            raise
        continue
        
    if runFlg == False:
        break
        
    print "connected by ", addr
    
    data = connectedFd.recv(1024)
    if not data:
        break
    print data
    #http_response_with_close(connectedFd)               # 流量器能正確處理
    #http_response(connectedFd)                          # 瀏覽器不能正確處理 pending
    #http_response_with_content_length(connectedFd)      # 瀏覽器能正確處理
    http_response_chunked(connectedFd)                  # 瀏覽器能正確處理
else:
    print "runFlg ", runFlg
    
print "Done"