Python脚本检查Namenode状态

Question

I am new to Python and currently only learned a few things by researching online. Just wanted to know why am i getting "error" as the output rather than "success". Please see code below:

#! /usr/bin/python -v

import os
import subprocess

f = os.popen("hdfs haadmin -getServiceState nn2")
now = f.read()
status = "active"
if now == status:
        print "success"
else:
        print 'error'

Thanks, Anil

Answer 1

(moving comment to an answer)

Whenever pulling text from something like popen or anywhere, I like to use .strip() and usually .lower() to clean off the newlines and extra spaces.

#! /usr/bin/python -v

import os
import subprocess

f = os.popen("hdfs haadmin -getServiceState nn2")
now = f.read().lower().strip()  # add strip here

if now == "active":
        print "success"
else:
        print 'error:', now  # why not print out what it output?