Python tcp傳輸代碼實(shí)例解析

# -*- coding:utf-8 -*-
import socket
server = socket.socket()
server.bind(("0.0.0.0", 8888))
server.listen(10)
while True: #循環(huán)監(jiān)聽(tīng)連接過(guò)來(lái)的客戶(hù)端
  conn,addr = server.accept()
  while True: #每個(gè)客戶(hù)端連接過(guò)來(lái)以后持續(xù)交互，當(dāng)客戶(hù)端端斷開(kāi)后在和下一個(gè)客戶(hù)端交互
    try:
      rec_data = conn.recv(4096) #4096接收緩沖區(qū)大小
      if len(rec_data) == 0:
        break
      print("rec_data:", rec_data.decode(encoding="utf-8"))
      conn.send(rec_data.upper())
    except ConnectionResetError as e:
      print("一個(gè)客戶(hù)端關(guān)閉了連接")
      break
server.close()

import socket
client = socket.socket()
client.connect(("127.0.0.1", 8888))
while True:
  msg = input()
  if len(msg) == 0:
    continue
  client.send(msg.encode(encoding="utf-8")) #如果發(fā)送中文需要對(duì)其進(jìn)行encode，接收也需要decode；英文前面直接加b指定類(lèi)型
  client_rec = client.recv(4096)
  print("client_rec:", client_rec)
client.close()

import socket, os
server = socket.socket()
server.bind(("0.0.0.0", 8888))
server.listen(10)
while True: #循環(huán)監(jiān)聽(tīng)連接過(guò)來(lái)的客戶(hù)端
  conn,addr = server.accept()
  while True: #收到客戶(hù)端發(fā)過(guò)來(lái)的get filename如果filename存在就將文件發(fā)出否則返回文件不存在
    try:
      rec_data = conn.recv(1024) #4096接收緩沖區(qū)大小
      if len(rec_data) == 0:
        break
      rec_str_list = rec_data.decode(encoding="utf-8").split(" ")
      filename = rec_str_list[-1]
      if os.path.isfile(filename):#判斷文件在當(dāng)前路徑下存在句將文件傳給客戶(hù)端
        file_data = open(filename,encoding="utf-8").read()
        conn.send(str(len(file_data)).encode(encoding="utf-8")) #將文件長(zhǎng)度傳給客戶(hù)端
        print(conn.recv(1024).decode(encoding="utf-8")) #客戶(hù)端收到文件長(zhǎng)度返回確認(rèn)信息，server收到確認(rèn)信息后再開(kāi)始傳送數(shù)據(jù)
        conn.sendall(file_data.encode(encoding="utf-8"))#將數(shù)據(jù)全部發(fā)個(gè)客戶(hù)端，客戶(hù)端判斷數(shù)據(jù)接收完成后發(fā)送接收完成的信息
        print(conn.recv(1024).decode(encoding="utf-8")) #接收客戶(hù)端接收完成的確認(rèn)指令，避免兩個(gè)send直接連在一起產(chǎn)生粘包
      else:#如果文件名不存在則返回文件不存在
        conn.send(b"file is not exit")
    except ConnectionResetError as e:
      print("一個(gè)客戶(hù)端關(guān)閉了連接")
      break
server.close()

import socket, os
#輸入get 文件名，當(dāng)文件存在server家目錄下則返回文件，客戶(hù)端將接收文件內(nèi)容并打印，
client = socket.socket()
client.connect(("127.0.0.1", 8888))
while True:
  msg = input()
  if len(msg) == 0:
    continue
  client.send(msg.encode(encoding="utf-8")) #如果發(fā)送中文需要對(duì)其進(jìn)行encode，接收也需要decode；英文前面直接加b指定類(lèi)型
  client_rec = client.recv(1024).decode(encoding="utf-8")
  print("client_rec", client_rec)
  if client_rec == "file is not exit": #如果文件不存在則用戶(hù)打印文件不存在，用戶(hù)繼續(xù)輸入
    print(client_rec)
    continue
  client.send(client_rec.encode(encoding="utf-8"))#文件存在則將文件大小發(fā)回去
  rec_len = int(client_rec)
  print("rec_len", rec_len)
  file_len = 0
  new_file = open("new_file","a",encoding="utf-8")
  while file_len < rec_len:#開(kāi)始循環(huán)接收文件直到接收的文件大小與server端發(fā)過(guò)來(lái)的大小一樣,將接收到的數(shù)據(jù)寫(xiě)入新文件
    rec_data_tmp = client.recv(1024)
    file_len += len(rec_data_tmp)
    print("receive date len", file_len)
    new_file.write(rec_data_tmp.decode(encoding="utf-8"))
  client.send("receive all".encode(encoding="utf-8"))

client.close()