Deploying Python code to Traffic Manager - Pulse Secure Community

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You've deployed the PyRunner.jar extension to Traffic Manager so that you can run Python code (see PyRunner.jar: Running Python code in Traffic Manager). What's the easiest way to deploy the Python code on Traffic Manager?

The following script makes this easy. It runs a quick syntax check against the Python code, then uses the REST API (Tech Tip: Using the RESTful Control API with Python - Overview) to PUT the python file in the conf/extra part of the Traffic Manager configuration.

publish.py

The source of the publish script:

#!/usr/bin/python

import requests
import sys
import py_compile

# FIXME: these need to be correct for your deployment
url  = 'https://stingray:9070/api/tm/1.0/config/active/'
auth = ( 'admin', 'admin' )

file = sys.argv[1]

# Syntax-check script before uploading
try:
  py_compile.compile( file, '/dev/null', file, True )
except Exception, e:
  print "Compilation check failed:", e
  sys.exit( 1 )

src=open( file, 'r' ).read()

# Deploy to Stingray
client = requests.Session()
client.auth = auth
client.verify = 0

try:
    response = client.put( url+'extra/'+file, data = src )
except Exception, e:
    print "Error: Unable to connect to " + url + ": ", e
    sys.exit( 1 )

print "Uploaded " + file

Save this script on your development environment, check the URL and auth parameters, and make the script executable (chmod +x).

Deploying Python code to Traffic Manager

Upload the PyRunner.jar file to Traffic Manager, as per the instructions in PyRunner.jar: Running Python code in Traffic Manager.

Create a simple TrafficScript rule and associate it with your virtual server:

java.run( "PyRunner", "vars.py" );

Create a python file named vars.py

from javax.servlet.http import HttpServlet

class vars(HttpServlet):
   def doGet(self, request, response):
      reqsText =  '   %30s: %s\n' % ( "URL", request.getRequestURL() )
      reqsText += '   %30s: %s\n' % ( "URI", request.getRequestURI() )
      reqsText += '   %30s: %s\n' % ( "Query String", request.getQueryString() )

      headText = ''
      names = request.getHeaderNames()
      for n in names:
            headText += '   %30s: %s\n' % ( n, request.getHeader( n ) )

      paramText = ''
      names = request.getParameterNames()

      for n in names:
            paramText += '   %30s: %s\n' % ( n, request.getParameter( n ) )      

      attrText = ''
      names = request.getAttributeNames()

      for n in names:
            attrText += '   %30s: %s\n' % ( n, request.getAttribute( n ) )
      attrText += '   %30s: %s\n' % ( "args", request.getAttribute( "args" ) )

      toClient = response.getWriter()
      response.setContentType ("text/html")
      htmlOut = '''
         <html><head><title>vars.py</title><body>
         <h3>Request</h3><pre>%s</pre>
         <h3>Headers</h3><pre>%s</pre>
         <h3>Parameters</h3><pre>%s</pre>
         <h3>Attributes</h3><pre>%s</pre>
      ''' % ( reqsText, headText, paramText, attrText )

      toClient.println(htmlOut)

Upload it using publish.py:

$ ./publish.py vars.py
Uploaded vars.py

Then test it out!

The key advantage of this technique is that it makes publishing Python/Jython code very quick and easy. Traffic Manager will notice that the Python code has changed and re-load it immediately, giving you a quick test cycle.