網路程式設計 HW10

第一題 一送一收，觀察檢查表的運作

畫面截圖

Server

import select
import socket

HOST = '127.0.0.1'
PORT = 8000

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((HOST, PORT)) 
s.listen(1)
conn = None
print("Server is running...")


while True:
    try:
        conn, addr = s.accept()
    except:
        time.sleep(1)
    else:
        conn.setblocking(0)
        print("Connected")
        while True:
            try:
                print("[1]clear the socket fd set.")
                get = []
                print("[2]add client socket to fd set")
                get.append(conn)
                print("[3]call select() and waiting")
                read, out, ex = select.select(get, [], [], None)
                act = len(read) + len(out) + len(ex)
                print("[4]wake up from select():" + str(act))
                for sk in read:
                    if sk is conn:
                        data = conn.recv(1024)
                        if not data:
                            print("Connection closed.")
                            s.close()
                            break
                        else:
                            print("recv:", data.decode(), "(in 10 sec)")
            except:
                pass

Client

import socket
import time

HOST = '127.0.0.1'  
PORT = 8000

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
word = "How are you?"
while True:
    try:
        s.connect((HOST, PORT))
    except:
        print("err")
        time.sleep(1)
    else:
        print('Connected to', HOST)
        s.setblocking(0)
        while True:
            time.sleep(10)
            s.sendall(word.encode())
            print("Send:", word, "(in 10 sec)")

第二題 增加為兩個client，server會echo

畫面截圖

Server

import select
import socket
import time
HOST = '127.0.0.1'
PORT = 8000

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((HOST, PORT)) 
s.listen(2)
conn1 = None
conn2 = None
print("Server is running...")

while True:
    try:
        conn1, addr1 = s.accept()
        conn2, addr2 = s.accept()
    except:
        time.sleep(1)
    else:
        conn1.setblocking(0)
        conn2.setblocking(0)
        print("1 Connected")
        print("2 Connected")
        while True:
            time.sleep(10)
            try:
                print("[1]clear the socket fd set.")
                get = []
                print("[2]add client socket to fd set")
                get.append(conn1)
                get.append(conn2)
                print("[3]call select() and waiting")
                read, out, ex = select.select(get, [], [], None)
                act = len(read) + len(out) + len(ex)
                print("[4]wake up from select():" + str(act))
                for sk in read:
                    if sk is conn1:
                        data = conn1.recv(1024)
                        if not data:
                            print("Connection closed.")
                            s.close()
                            break
                        else:
                            print("recv from client1:", data.decode(), "(in 10 sec)")
                            conn1
                            s.sendall(data)
                    if sk is conn2:
                        data = conn2.recv(1024)
                        if not data:
                            print("Connection closed.")
                            s.close()
                            break
                        else:
                            print("recv rom client2:", data.decode(), "(in 10 sec)")
                            conn2.sendall(data)
            except:
                pass

Client

import socket
import time

HOST = '127.0.0.1'  
PORT = 8000

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
word = "How are you?"
while True:
    try:
        s.connect((HOST, PORT))
    except:
        print("err")
        time.sleep(1)
    else:
        print('Connected to', HOST)
        s.setblocking(0)
        while True:
            time.sleep(10)
            try:
                s.sendall(word.encode())
                print("Send:", word, "(in 10 sec)")
                data = s.recv(1024)
                print("recv:", data.decode())
            except:
                pass

第三題 服務多個client的echo server

畫面截圖

Server

import select
import socket
import time

client = []
HOST = '127.0.0.1'
PORT = 8000

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((HOST, PORT))
s.setblocking(False) 
s.listen(5)

print("Server is running...")
get = []

while True:
    print("[1]clear the socket fd set.")
    get = []
    print("[2]add sevet to fd set")
    get.append(s)
    print("[2]add client socket to fd set")
    for i in client:
         get.append(i)
    print("[3]call select() and waiting")
    read, out, ex = select.select(get, [], [], None)
    act = len(read) + len(out) + len(ex)
    print("[4]wake up from select():" + str(act))
    for sk in read:
        if sk is s:
            conn, addr = s.accept()
            print("New connection: ", str(addr))
            client.append(conn)
        for i in client:
            if sk is i:
                data = i.recv(1024)
                if not data:
                    print("client closed connection")
                    client.pop(client.index(i))
                    i.close()
                    break
                else:
                    i.sendall(data)
                    print("recv from and echo to client[", client.index(i), "]: ",data.decode())

Client

import socket
import time

HOST = '127.0.0.1'  
PORT = 8000

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
word = "How are you?"
while True:
    try:
        s.connect((HOST, PORT))
    except:
        print("err")
        time.sleep(1)
    else:
        print('Connected to', HOST)
        s.setblocking(0)
        while True:
            time.sleep(10)
            try:
                s.sendall(word.encode())
                print("Send:", word, "(in 10 sec)")
                data = s.recv(1024)
                print("recv:", data.decode())
            except:
                pass

第四題 使用writefds來傳送

畫面截圖

Server

import select
import socket
import time

HOST = '127.0.0.1'
PORT = 8000

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((HOST, PORT)) 
s.listen(5)
server = [s]

print("Server is running...")

client = []
msg = ''

conn, addr = s.accept()
client.append(conn)
while True:
    print("[1]clear the socket fd set.")
    readfds = []
    writefds = []
    print("[2]add server to fd set")
    readfds.append(s)
    print("[2]add client socket to fd set")
    for i in client:
        if len(msg) == 0:
            readfds.append(i)
        else:
            writefds.append(i)
    print("[3]call select() and waiting")
    act = select.select(readfds, writefds, [], None)
    print("[4]wake up from select()")
    for i in client:
        if i in readfds:
            data = i.recv(1024)
            msg = data.decode()
            print("recv from client", client.index(i), ': ', data.decode())
            
        if i in writefds:
            i.sendall(msg.encode())
            msg = ''

Client

import socket
import time

HOST = '127.0.0.1'  
PORT = 8000

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
word = "How are you?"
while True:
    try:
        s.connect((HOST, PORT))
    except:
        print("err")
        time.sleep(1)
    else:
        print('Connected to', HOST)
        s.setblocking(0)
        while True:
            time.sleep(10)
            try:
                s.sendall(word.encode())
                print("Send:", word, "(in 10 sec)")
                data = s.recv(1024)
                print("recv:", data.decode())
            except:
                pass

第五題 使用timeout

畫面截圖

Server

import select
import socket
import time

HOST = '127.0.0.1'
PORT = 8000

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((HOST, PORT)) 
s.listen(5)
server = [s]

print("Server is running...")

client = []
msg = ''

conn, addr = s.accept()
client.append(conn)
while True:
    print("[1]clear the socket fd set.")
    readfds = []
    writefds = []
    print("[2]add server to fd set")
    readfds.append(s)
    print("[2]add client socket to fd set")
    for i in client:
        if len(msg) == 0:
            readfds.append(i)
        else:
            writefds.append(i)
    print("[3]call select() and waiting")
    act = select.select(readfds, writefds, [], 5)
    #print(type(act))
    print("[4]wake up from select()")
    if act == ([], [], []):
        print("select() is waiting for 5 sec")
    else:
        for i in client:
            if i in readfds:
                data = i.recv(1024)
                msg = data.decode()
                print("recv from client", client.index(i), ': ', data.decode())
                
            if i in writefds:
                i.sendall(msg.encode())
                msg = ''

Client

import socket
import time

HOST = '127.0.0.1'  
PORT = 8000

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
word = "How are you?"
while True:
    try:
        s.connect((HOST, PORT))
    except:
        print("err")
        time.sleep(1)
    else:
        print('Connected to', HOST)
        s.setblocking(0)
        while True:
            time.sleep(10)
            try:
                s.sendall(word.encode())
                print("Send:", word, "(in 10 sec)")
                data = s.recv(1024)
                print("recv:", data.decode())
            except:
                pass

心得

自從有附上python的程式碼之後，就能比較輕鬆地做完了