TCP data sending from python to logstash fails

Question

I am trying to send data from python script over TCP and receive the same in the logstash. But there is no exchange of data happening.

logstash.conf

input {
  tcp {
      port => 5959
      codec => json
  } 
}

filter{

}

output {
    stdout {codec => rubydebug}
}

python :

import json
import socket
import sys

HOST = "127.0.0.1"
PORT = 5959

try:
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
except socket.error, msg:
    sys.stderr.write("[ERROR] %s\n" % msg[1])
    sys.exit(1)

try:
    sock.connect((HOST, PORT))
except socket.error, msg:
    sys.stderr.write("[ERROR] %s\n" % msg[1])
    sys.exit(2)

msg = {'@message': 'python test message', '@tags': ['python', 'test']}

sock.sendall(json.dumps(msg))
sock.send('\n')
sock.close()
sys.exit(0)

After executing both the scripts I am neither getting any error nor data in the logstash so can someone help like what can be causing the issue.

Answer 1

I just added sock.send('\n') after sock.sendall(json.dumps(msg)) and it worked. It seems that there is an open issue with logstash-codec-json as1 :

The logstash 'json' plugin still requires a newline '\n' to terminate json logs being sent over a TCP input.2

References :

1. TCP data sending from pyton to logstash fails.

2. The logstash 'json' codec still requires a newline '\n' as a delimiter to terminate json logs being sent over a TCP input.