final touches on change_env

Author: danfinn

change_env.py

@@ -4,22 +4,13 @@
 import os
 import re
 import sys
-import fileinput
-
-if (len(sys.argv) < 2):
-        print "You must give a new environment name"
-        sys.exit()
-else:
-        new_env=sys.argv[1]
 
 def get_current_env():
         # Use regex to determine what MAXIS_ENV is currently set to
         etc_profile=open("/etc/profile","r")
-        regex=re.compile('MAXIS_ENV=(\w+)')
+        regex=re.compile('MAXIS_ENV=(\w+)$')
         for line in etc_profile:
                 env=regex.findall(line)
-        #etc_profile.close()
-        #print 'MAXIS_ENV is currently set to "%s"' % env[0]
         return env[0]
 
 def update_file(file,current_env,new_env):
@@ -32,18 +23,45 @@ def update_file(file,current_env,new_env):
         # Also open a file handle on the same file for writing
         new_file=open(file,'w')
         # Search and replace 
-        changed_data=current_file.replace(current_env,new_env)
+        full_current_env="export MAXIS_ENV=" + current_env
+        full_new_env="export MAXIS_ENV=" + new_env
+        changed_data=current_file.replace(full_current_env,full_new_env)
         # Write out the changed data to the file
         new_file.write(changed_data)
         #current_file.close()
         new_file.close()
         current_env=get_current_env()
         print 'MAXIS_ENV in %s has been changed to "%s"' % (file,current_env)
 
+def usage():
+        print ' ---------------------------------------------------------------------------'
+        print ''
+        print ' This script is used to change the environment settings to your particular '
+        print ' needs.  By default, any instances built from this AMI are named "standard".'
+        print ' Using this script you can change it to whatever is needed or desired.'
+        print ' '
+        print ' Usage : ./change_env.py newEnvironmentName'
+        print ' '
+        print ' '
+        print ' ---------------------------------------------------------------------------'
+        print ' '
+
+def main(new_env):
+        current_env=get_current_env()
+        print ""
+        print " ---------------------------------------------------------------------------"
+        print ""
+        print 'Currently MAXIX_ENV is set to "%s"' % current_env
+        print ""
+        update_file("/etc/profile",current_env,new_env)
+        update_file("/usr/bin/maxisenv",current_env,new_env)
+        print ""
+        print " ---------------------------------------------------------------------------"
+        print ""
+
 
-current_env=get_current_env()
-print ""
-print 'Currently MAXIX_ENV is set to "%s"' % current_env
-update_file("/etc/profile",current_env,new_env)
-update_file("/usr/bin/maxisenv",current_env,new_env)
-print ""
+if (len(sys.argv) < 2):
+        usage()
+else:
+        new_env=sys.argv[1]
+        main(new_env)