I have created a TCP multithreading webserver but it gives me the following
If the file is found
1. It says "int obj has no attribute encode"
2. Later, it will show list index out of range
If the file is not found
1. It does not display the html error message on the web browser
2. Later, it will show list index out of range
My server code is
import socket
import threading
import os
import sys
#to convert bytes into string
def bytestoString(stringToRead):
stringToRead = bytes.decode(stringToRead)
type(stringToRead)
return(stringToRead)
#to conver string into bytes
def stringToBytes(bytesToSend1):
bytesToSend1= str.encode(bytesToSend1)
type (bytes)
return(bytesToSend1)
#to retreive a file
def retrFile(name,sock):
message=sock.recv(1024)
message_string = bytestoString(message)
print(message_string)
fileName=message_string.split()[1]
fileName=fileName.split("/")[1]
#stringLength=len(fileName)
print(fileName)
if os.path.isfile(fileName):
print ('Ready to send the file................')
with open(fileName,'rb') as fileRead:
data= fileRead.read()
print (data)
exists_Bytes=stringToBytes('HTTP/1.1 200 OK\nContent-type=text/html')
sock.send(exists_Bytes)
for i in range(0 ,len(data)):
sock.send((data[i]).encode())
print('file sent succesfully')
sock.close()
else :
httpResponse=stringToBytes('HTTP/1.1 404 not Found')
sock.send(httpResponse)
#errorDisplayPage=stringToBytes('<html><title>404 Error</title><body>404 Error- Page cannot be found </body></html>')
sock.send(b'<html><title>404 Error</title><body>404 Error- Page cannot be found </body></html>')
print ('error message displayed')
sock.close()
def Main(serverPort):
#creating a server socket type TCP
serverSocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
localHost=socket.gethostname()
#binding the server to the client
serverSocket.bind((localHost,serverPort))
serverSocket.listen(5)
print ('***Server is ready to recieve***')
while True:
connectionSocket, addr = serverSocket.accept()
print ('got connection from:<', addr,'>')
t=threading.Thread(target=retrFile,args=('retrThread',connectionSocket))
t.start()
connectionSocket.send('thank you for connecting')
connectionSocket.close()
if __name__ == '__main__':
#getting server hostname and port number from the user
serverPort=int(sys.argv[1])
Main(serverPort)
You have opened your file as binary in your code:
with open(fileName,'rb') as fileRead:
data= fileRead.read()
However, later you try to do some funny things. Now, this differs in Python 2 and 3.You are using Python 3, so this following block is problematic:
for i in range(0 ,len(data)):
sock.send((data[i]).encode())
In python 2 you would iterate over individual chars and it would work fine. However, in python 3 you are iterating over a bytes object, so data[i] will be an int object.
Instead you can just:
sock.sendall(data)
Also according to wikipedia, the HTTP-protocol assumes that the status line is followed by an empty line. That is why you do not see the error message, and will not see the file.
So, postfix your status codes with "\n\n", so like: 'HTTP/1.1 404 not Found\n\n'. The same goes for the OK-message.
Related
I'm trying to complete this lab but cannot seem to get it to work correctly. When I try to get a file not present of the server, I am given
This page isn’t working
127.0.0.1 sent an invalid response.
ERR_INVALID_HTTP_RESPONSE
The response I'd like to get is along the lines of
404 File not found
When I try to load a file not present, the compiler says for line 16:
filename = message.split()[1]
IndexError: list index out of range
The code compiles and I am able to open my Hello World file, but I am just not able to get this 404 error. I was given a skeleton code, so there are some things that I cannot change without deviating from course material.
from socket import *
serverSocket = socket(AF_INET, SOCK_STREAM)
#Prepare a server socket
serverPort = 7000
serverSocket.bind(('127.0.0.1', serverPort))
serverSocket.listen(5)
while True:
print('Ready to serve...')
connectionSocket, addr = serverSocket.accept()
#Fill in start #Fill in end
try:
message = connectionSocket.recv(1024)
print (message)
filename = message.split()[1]
f = open(filename[1:])
outputdata = f.read()
#Send one HTTP header line into socket
#Fill in start
connectionSocket.send('\nHTTP/1.x 200 OK\n'.encode())
#Fill in end
#Send the content of the requested file to the client
for i in range(0, len(outputdata)):
connectionSocket.send(outputdata[i].encode())
connectionSocket.send("\r\n".encode())
connectionSocket.close()
print ('File Recieved')
except IOError:
connectionSocket.send('\n404 File Not Found\n'.encode())
connectionSocket.close()
#Close client socket
serverSocket.close()
sys.exit()
The skeleton code appears to be Python 2, and I'm using Python 3. I've made some minor syntax adjustments to adjust.
Removing print(message) yields "File Recieved" in the compiler, but still no 404 error in the browser. I'm at loss after 8 hours.
One way to handle an IndexError in message.split()[1] is to handle and IndexError in message.split()[1] ;)
try:
filename = message.split()[1]
except IndexError:
send_404_response()
continue
I am writing a very simple Python socket program to read an HTML body from the server. If I create a HelloWorld.html file and open it with the designated host and port, I can open the file in my browser with the following server and read the message in the HTML file. However, I am having trouble reading in the same information from my client.
Server
from socket import *
serverSocket = socket(AF_INET,SOCK_STREAM)
host = '127.0.0.1'
port = 6789
serverSocket.bind((host,port))
serverSocket.listen(5)
print("server started...")
(connectionSocket, addr) = serverSocket.accept()
try:
message = connectionSocket.recv(1024).decode()
filename = message.split()[1]
f = open(filename[1:]) # Throws IOError if file not found
print(filename, "found")
connectionSocket.send("HTTP/1.0 200 OK\r\n".encode())
connectionSocket.send("Content-Type: text/html\r\n".encode())
connectionSocket.send(message.encode())
outputdata = f.read()
for i in range(0, len(outputdata)):
connectionSocket.send(outputdata[i].encode())
connectionSocket.send("\r\n".encode())
connectionSocket.close()
print(filename, "delivered")
except IOError:
print(filename, "NOT found")
connectionSocket.send('HTTP/1.0 404 NOT FOUND\r\n')
connectionSocket.close()
print("file not found message delivered")
serverSocket.close()
print("server closed...")
My server seems to be working. However, when my client tries to send the HTML object path to the socket and have the server read it, it does not seem to be picking up the message. I have just started socket programming in Python and I am trying to understand how the server receives the message from the socket. My initial thought was if I send the path of the HTML object (located in same directory as client and server) to the socket, the server should be able to read that information, open it, and return the information to the client.
Client
from socket import *
import sys
client = socket(AF_INET, SOCK_STREAM)
host = sys.argv[1]
port = sys.argv[2]
obj = sys.argv[3]
port = int(port)
client.connect((host, port))
print(client.getsockname())
request = obj
client.send("hello".encode())
client.send(request.encode())
s = client.recv(1024).decode()
print(s)
For my client, I accept the host,port, and the path to the HTML from a commandline argument and establish a connection.
When I run the browser for my HTML file with the url http://127.0.0.1:6789/HelloWorld.html, the server responds well. However, when I run the server and run the client with the command py capClient.py 127.0.0.1 6789 HelloWorld.html on the shell, it returns the filename = message.split()[1] IndexError: list index out of range error. I am assuming that this problem is coming from the server not being able to split the message coming in from the connectionSocket as an acceptable HTML object path.
What are some tips on modifying the client code to receive HTML file from servers?
This trouble is because you await message string is 'hello HelloWorld.html', but it is 'helloHelloWorld.html' and split() get you list ['helloHelloWorld.html'] where index 1 not exists.
f = open(filename[1:])
# must be replaced with [1:] give you a list, not string
f = open(filename)
# there needs encode()
connectionSocket.send('HTTP/1.0 404 NOT FOUND\r\n'.encode())
Im having trouble getting my very basic and simple TCP Server to properly work with http requests. This is what I have so far
from socket import *
import sys
serverSocket = socket(AF_INET, SOCK_STREAM)
serverSocket.bind(('', 4567))
serverSocket.listen(1)
while True:
print('Ready to serve...')
connectionSocket, addr = serverSocket.accept()
print("connected from: ", addr)
try:
message = connectionSocket.recv(1024)
filename = message.split()[1]
f = open(filename[1:])
outputdata = f.read()
connectionSocket.send("HTTP/1.1 200 OK\r\n")
for i in range(0, len(outputdata)):
connectionSocket.send(outputdata[i].encode())
connectionSocket.send("\r\n".encode())
connectionSocket.close()
except IOError:
connectionSocket.send("file not found")
serverSocket.close()
sys.exit()
The error comes from the open statement. I dont fully understand how this line of code's return value is organized.
message = connectionSocket.recv(1024)
I know that the return value is in bytes but when I try to use a fuction to turn it into a string like decode() i get errors as well
I have the .py file and the html file sitting in the same directory on my local machine and the way I test this is I just run this and open up a browser and type in
http://127.0.0.1:4567/helloworld.html
My code then promptly crashes after receiving the HTTP request.
Any and all help will be greatly appreciated!
There are numerous problems with your code and since you don't state what specific issues you are concerned about, here is what I see:
connectionSocket.send(outputdata[i].encode())
connectionSocket.send("\r\n".encode())
That appears to send a newline after every character you send back to the client.
Also, it doesn't deal with the client disconnecting because you're sending back invalid data.
Even if what you were trying to do didn't have these errors in it, you don't appear to be attempting to send back a valid http response.
https://www.w3.org/Protocols/rfc2616/rfc2616-sec6.html
This is the client and server program where a client sends a file to server to save in the server. There is a issuse in that same file name is not getting copied on the server with same file size
Please help me in this
Client program
import socket
import sys
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect(("localhost",9999))
path=raw_input("Please enter the complete PATH of your file : ")
f=open (path, "rb")
l = f.read(256)
while (l):
s.sendall(l)
l = f.read(10000)
s.close()
Server Program
import socket
import sys
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind(("localhost",9999))
s.listen(10)
while True:
s, address = s.accept()
print address
i=1
f = open( str(i),'wb') #open in binary
#i=i+1
while (True):
l=s.recv(256)
#while (l):
f.write(l)
l=s.recv(256)
print 'File recieve succesfully'
f.close()
#sc.close()
s.close()
Thanks in advance
Start by walking through the code and thinking about what the client knows about the data it is sending and what the server knows about the data it is receiving. You will have to send 2 types of messages: the data and the filename. How you do that is up to you.
Without over-thinking it, maybe try writing the filename first (followed by a newline or special character) then send the file data. On the server side accept the connection, read in data until you find a newline character (that's the filename), then receive the rest of the data and write it to the file.
Also, the server code you've provided doesn't work, at least I don't think, since you never break out of your while True loops.
I am trying to program compilation server which compiles a C program sent by client and returns an object file which can then be linked and executed at the client. Here are my client and server programs respectively
client.py:
# Compilation client program
import sys, socket, string
File = raw_input("Enter the file name:")
ssock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
ssock.connect(('localhost', 5000))
csock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
csock.connect(('localhost', 5001))
f = open(File, "rb")
data = f.read()
f.close()
ssock.send(File) #send filename
ssock.send(data) #send file
fd=raw_input("Enter a key to start recieving object file:")
data=csock.recv(1024) #receive status
if data=="sucess\n":
File=File.replace(".c",".o") #objectfile name
print "Object file, "+File+", recieved sucessfully"
else:
print "There are compilation errors in " + File
File="error.txt" #errorfile name
print "Errors are reported in the file error.txt"
fobj=open(File,"wb")
while 1:
data=ssock.recv(1024) # if any error in c sourcefile then error gets
# eported in errorfile "error.txt" else objectfile is
# returned from server
if not data:break
fobj.write(data)
fobj.close()
ssock.close()
csock.close()
server.py
#Compilation Server program
import subprocess
import socket, time, string, sys, urlparse, os
ssock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
ssock.bind(('', 5000))
ssock.listen(2)
print 'Server Listening on port 5000'
csock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
csock.bind(('', 5001))
csock.listen(2)
print 'Control server listening on port 5001'
client, claddr = ssock.accept()
controlsoc, caddr = csock.accept()
filename=client.recv(1024) #receive filename
print filename
############### This code is not working, i'm not getting the reason #######
############### I want to receive a file more than 1KB from client #######
f = open(filename,"wb") #receive file======
while 1:
data = client.recv(1024)
if not data: break
f.write(data)
f.close()
###############
###############
data="gcc -c " + filename + " 2> error.txt" #shell command to execute c source file
#report errors if any to error.txt
from subprocess import call
call(data,shell=True) #executes the above shell command
fil = filename.replace(".c",".o")
if (os.path.isfile(fil))== True: #test for existence of objectfile
data = "sucess\n" #no objectfile => error in compilation
filename = filename.replace(".c",".o")
else:
data = "unsucessful\n"
print data+"hi"
filename = "error.txt"
controlsoc.send(data)
f = open(filename,"rb")
data=f.read()
f.close()
print data
client.send(data)
client.close()
controlsoc.close()
I'm not able to recieve files of multiple KB. Is there any flaw in my code or how should i modify my code in order to achieve my objective of coding a compilation server.
Please help me with this regard..Thanks in advance
The problem here is you assume that ssock.send(File) will result in filename=client.recv(1024) reading exactly the filename and not more, but in fact the receiving side has no idea where the filename ends and you end up getting the file name and part of the data in the filename variable.
TCP connection is a bi-directional stream of bytes. It doesn't know about boundaries of your messages. One send might correspond to more then one recv on the other side (and the other way around). You need an application-level protocol on top of raw TCP.
The easiest in your case would be to send a text line in the form file-size file-name\n as a header. This way your server would be able to not only separate header from file data (via newline) but also know how many bytes of file content to expect, and reuse same TCP connection for multiple files.