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Python - Send Integer or String to Spark-Streaming

I can send my data through CSV file. First, write my random numbers into CSV file then send it, but is it possible to send it directly?
my socket code:
import socket
host = 'localhost'
port = 8080
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((host, port))
s.listen(1)
while True:
print('\nListening for a client at',host , port)
conn, addr = s.accept()
print('\nConnected by', addr)
try:
print('\nReading file...\n')
while 1:
out = "test01"
print('Sending line', line)
conn.send(out)
except socket.error:
print ('Error Occured.\n\nClient disconnected.\n')
conn.close()
spark streaming code:
from pyspark import SparkContext
from pyspark.streaming import StreamingContext
sc = SparkContext("local[2]","deneme")
ssc = StreamingContext(sc, 10)
socket_stream = ssc.socketTextStream("localhost",8080)
random_integers = socket_stream.window( 30 )
digits = random_integers.flatMap(lambda line: line.split(" ")).map(lambda digit: (digit, 1))
digit_count = digits.reduceByKey(lambda x,y:x+y)
digit_count.pprint()
ssc.start()

This is because socket blocks sending the data and never moves on. The most basic solution is to send some amount of data and close the connection:
import socket
import time
host = 'localhost'
port = 50007
i = 0
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((host, port))
s.listen(1)
try:
while True:
conn, addr = s.accept()
try:
for j in range(10):
conn.send(bytes("{}\n".format(i), "utf-8"))
i += 1
time.sleep(1)
conn.close()
except socket.error: pass
finally:
s.close()
To get something more interesting check non-blocking mode with timeouts.

python socket : server must send a message before recv

In socket, I found that if server does not send any message before call recv(), server will be no response, whatever using mutilthread or not.
As the figure shows below:
enter image description here
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server.py(Using SocketServer module):
def handle(self):
conn = self.request
# conn.send('Welcome to server')
flag = True
while flag:
data = conn.recv(1024)
print 'client:' + data
if data == 'exit':
flag = False
conn.send('AAAAAA')
conn.close()
client.py:
client = socket.socket()
ip_port = ('127.0.0.1', 11111)
client.connect(ip_port)
while True:
data = client.recv(1024)
print 'server:' + data
send = raw_input('client:')
client.send(send)
if send == 'exit':
sys.exit()
I would appreciate it very much if you would help me with it.

# server.py
import socket
TCP_IP = '127.0.0.1'
TCP_PORT = 5005
BUFFER_SIZE = 1024
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((TCP_IP, TCP_PORT))
s.listen(1)
conn, addr = s.accept()
print 'Connection address:', addr
while 1:
data = conn.recv(BUFFER_SIZE)
if not data: break
print "Server received data:", data
conn.send("Data received at server side")
conn.close()
# client.py
import socket
TCP_IP = '127.0.0.1'
TCP_PORT = 5005
BUFFER_SIZE = 1024
MESSAGE = "Hello World!"
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((TCP_IP, TCP_PORT))
s.send(MESSAGE)
print "Client: " + MESSAGE
data = s.recv(BUFFER_SIZE)
s.close()
print data
I think providing a sample code could speak itself.
# Expected input:
python server.py
python client.py
# Expected output:
# (server output)
Connection address: ('127.0.0.1', 62136)
Server received data: Hello World!
# (client output)
Client: Hello World!
Data received at server side
You could find out your missing component by comparing the code,such as bind().
Hope it help.
With reference to this site: https://wiki.python.org/moin/TcpCommunication

I got problems with making a Python socket server receive commands from a Python socket client

I got problems with making a Python socket server receive commands from a Python socket client. The server and client can send text to each other but I can't make text from the client trigger an event on the server. Could any one help me? I'm using Python 3.4.
server.py
import socket
host = ''
port = 1010
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((host, port))
s.listen(1)
conn, addr = s.accept()
print ("Connection from", addr)
while True:
databytes = conn.recv(1024)
if not databytes: break
data = databytes.decode('utf-8')
print("Recieved: "+(data))
response = input("Reply: ")
if data == "dodo":
print("hejhej")
if response == "exit":
break
conn.sendall(response.encode('utf-8'))
conn.close()
In server.py I tried to make the word "dodo" trigger print("hejhej").
client.py
import socket
host = '127.0.0.1'
port = 1010
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((host, port))
print("Connected to "+(host)+" on port "+str(port))
initialMessage = input("Send: ")
s.sendall(initialMessage.encode('utf-8'))
while True:
data = s.recv(1024)
print("Recieved: "+(data.decode('utf-8')))
response = input("Reply: ")
if response == "exit":
break
s.sendall(response.encode('utf-8'))
s.close()

Everything here works fine but, maybe not the way you want it to. If you switch the order on a couple of the lines it will display your event string before you enter your server response.
import socket
host = ''
port = 1010
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((host, port))
s.listen(1)
conn, addr = s.accept()
print ("Connection from", addr)
while True:
databytes = conn.recv(1024)
if not databytes: break
data = databytes.decode('utf-8')
print("Recieved: "+(data))
if data == "dodo": # moved to before the `input` call
print("hejhej")
response = input("Reply: ")
if response == "exit":
break
conn.sendall(response.encode('utf-8'))
conn.close()

Cannot Get Strings Across in a Socket Program

I have been looking at some code for a small chat program that I found online. It was originally written for 2.7, but it seems to work with 3.2. The only problem is that I cannot send strings, only numbers:
The chat.py file source code:
from socket import *
HOST = ''
PORT = 8000
s = socket(AF_INET, SOCK_STREAM)
s.bind((HOST, PORT))
s.listen(1)
conn, addr = s.accept()
print ('Connected by ' + str(addr))
i = True
while i is True:
data = conn.recv(1024)
print ("Received " + repr(data))
reply = str(input("Reply: "))
conn.send(reply)
conn.close()
And the client.py source file:
from socket import *
HOST = ''
PORT = 8000
s = socket(AF_INET, SOCK_STREAM)
s.connect((HOST, PORT)) # client-side, connects to a host
while True:
message = str(input("Your Message: "))
s.send(message)
print ("Awaiting reply...")
reply = s.recv(1024) # 1024 is max data that can be received
print ("Received " + repr(reply))
s.close()
When I run these using two separate terminals, they work, but do not send strings.
Thank you

When you work with sockets, the message you're passing around should probably be in bytes, b'bytes'. In Python 2.x, a str is actually what a bytes is in Python 3.x
So your message should be something like:
message = b'Message I want to pass'
Check here http://docs.python.org/3.3/library/stdtypes.html for more information.
According to http://docs.python.org/3/library/functions.html#input input returns a str, which means you'll have to encode message into bytes as such:
message = message.encode()
Do verify that this is the right approach to convert str to bytes by checking the type of message.

Your socket code is correct, it was just failing due to an unrelated error due to raw_input vs input. You probably intended to read a string from the shell instead of reading a string and trying to evaluate it as Python code which is what input does.
Try this instead:
chat.py
from socket import *
HOST = ''
PORT = 8000
s = socket(AF_INET, SOCK_STREAM)
s.bind((HOST, PORT))
s.listen(1)
conn, addr = s.accept()
print ('Connected by ' + str(addr))
i = True
while i is True:
data = conn.recv(1024)
print ("Received " + repr(data))
reply = str(raw_input("Reply: "))
conn.send(reply)
conn.close()
client.py
from socket import *
HOST = ''
PORT = 8000
s = socket(AF_INET, SOCK_STREAM)
s.connect((HOST, PORT)) # client-side, connects to a host
while True:
message = str(raw_input("Your Message: "))
s.send(message)
print ("Awaiting reply...")
reply = s.recv(1024) # 1024 is max data that can be received
print ("Received " + repr(reply))
s.close()

python 3.3 socket TypeError

I am trying to make a timestamp server and client. The client code is:
from socket import *
HOST = '127.0.0.1' # or 'localhost'
PORT = 21567
BUFSIZ = 1024
ADDR = (HOST, PORT)
tcpCliSock = socket(AF_INET, SOCK_STREAM)
tcpCliSock.connect(ADDR)
while True:
data = input('> ')
if not data:
break
tcpCliSock.send(data)
data = tcpCliSock.recv(BUFSIZ)
if not data:
break
print(data.decode('utf-8'))
tcpCliSock.close()
and the server code is:
from socket import *
from time import ctime
HOST = ''
PORT = 21567
BUFSIZ = 1024
ADDR = (HOST, PORT)
tcpSerSock = socket(AF_INET, SOCK_STREAM)
tcpSerSock.bind(ADDR)
tcpSerSock.listen(5)
while True:
print('waiting for connection...')
tcpCliSock, addr = tcpSerSock.accept()
print('connected from: ', addr)
while True:
data = tcpCliSock.recv(BUFSIZ)
if not data:
break
tcpCliSock.send('[%s] %s' % (bytes(ctime(), 'utf-8'), data))
tcpCliSock.close()
tcpSerSock.close()
The server is working fine but when I send any data to the server from the client I get the following error:
File "tsTclnt.py", line 20, in <module>
tcpCliSock.send(data)
TypeError: 'str' does not support the buffer interface

You need to encode the string in data to a buffer using the appropriate codepage. For example:
data = input('> ')
if not data:
break
tcpCliSock.send(data.encode('utf-8'))
The server code needs to change too:
response = '[%s] %s' % (ctime(), data.decode('utf-8'))
tcpCliSock.send(response.encode('utf-8'))
See more at:
How do I convert a string to a buffer in Python 3.1?