Question

我尝试使用＆＃34; persistent＆＃34;在http上发送图像流。连接。我在标题中保持活着，客户端（firefox）也是如此，但我不知道如何发送第二个请求或如何包装它。

我已经阅读了rfc。我也在查看流媒体服务时就像我试图复制的服务一样。我没有看到任何http消息在数据流传输时来回传播（mjpg流媒体）

所以我的问题是，在http持久连接中发送回客户端需要什么？如果我只是发送完全形成的http响应或只是jpg数据，客户端断开连接。如果我等待客户端在发送第二个映像之前发送更多数据，则客户端永远不会发送任何内容。

import socket
import sys
import time
import binascii
from thread import *

HOST = ''   # Symbolic name meaning all available interfaces
PORT = 9998 # Arbitrary non-privileged port

in_file = open("picture.jpg", "rb") # opening for [r]eading as [b]inary
testJpg = in_file.read() # if you only wanted to read 512 bytes, do .read(512)
in_file.close()

in_file = open("picture2.jpg", "rb") # opening for [r]eading as [b]inary
testJpg2 = in_file.read() # if you only wanted to read 512 bytes, do .read(512)
in_file.close()

OddNumber = 0

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
print 'Socket created'

#Bind socket to local host and port
try:
    s.bind((HOST, PORT))
except socket.error , msg:
    print 'Bind failed. Error Code : ' + str(msg[0]) + ' Message ' + msg[1]
    sys.exit()

print 'Socket bind complete'

#Start listening on socket
s.listen(10)
print 'Socket now listening'

#Function for handling connections. This will be used to create threads
def clientthread(conn):
    global OddNumber, testJpg, testJpg2
    OddNumber = 0

    # get data from the client (assume its a http get request)
    data = conn.recv(1024)
    print("\r\n Got1: "+str(len(data)))
    #time.sleep(.05)
    while OddNumber < 30:


        # create a new reply 
        reply = "HTTP/1.0 200 OK\r\n"
        reply += "Server: MJPG-Streamer/0.2\r\n"
        reply += "Cache-Control: no-store, no-cache, must-revalidate, pre-check=0, post-check=0, max-age=0\r\n"
        reply += "Pragma: no-cache\r\n"
        reply += "Content-type: image/jpeg\r\n"
        # add in the content len
        if OddNumber % 2 == 0:
            reply += "Content-Length: "+str(len(testJpg))+"\r\n"
        else:
            reply += "Content-Length: "+str(len(testJpg2))+"\r\n"
        # add the keep alive portion
        reply += "Connection: Keep-Alive\r\n"
        # I think we need this
        reply += "\r\n"

        # I use this toggle to switch between different images so if it does "stream" i'll be able to see it 
        # flipping these images
        if OddNumber % 2 == 0:
            reply += testJpg
        else:
            reply += testJpg2

        # after the image
        reply += "\r\n"


        conn.sendall(reply)
        OddNumber += 1
        print("\r\n OddNum: "+str(OddNumber))
        data = conn.recv(1024)
        print("\r\n Got1: "+str(len(data)))
        print(str(data))
        #time.sleep(.05)

    #came out of loop
    conn.close()

#now keep talking with the client
while 1:
    #wait to accept a connection - blocking call
    conn, addr = s.accept()
    print 'Connected with ' + addr[0] + ':' + str(addr[1])

    #start new thread takes 1st argument as a function name to be run, second is the tuple of arguments to the function.
    start_new_thread(clientthread ,(conn,))

s.close()

除此之外，我想知道持久连接是否对我有效。我正在开发一个托管图像的嵌入式设备，类似于ipcamera。但我需要能够在向我发送图像时将不同的URL发送回设备。这可能在同一个端口上吗？

有人要求我在我的http回复中显示什么。这是你在python脚本中看到的。它是一个有效的http响应，如果我设置它可以正常工作连接：Keep-Alive \ r \ n＆＃34; 至连接：关闭\ r \ n＆＃34;

我想我的问题是，你在持久连接中需要做些什么。客户会发送更多＆＃34; get＆＃34;请求或是服务器预期流式传输某些数据？至少firefox只发送一个＆＃34; get＆＃34;请求，然后我发送带有图像的响应，但接下来发生了什么以保持它？

感谢目前为止提供的所有帮助。

Answer 1

我担心这是因为你在客户端和服务器中使用相同的套接字对象。你能把代码分成两个文件吗？一个用于服务器的文件和另一个用于客户端的文件（表示你的clientthread函数）。

在HTTP中，当客户端使用'keep-alive'获取HTTP响应时，无论您发送什么类型的数据，它都将保持TCP连接。

持久性http连接需要哪些数据和可用数据

1 个答案: