Use the Java Connector in a servlet to filter ArcXML requests

Summary

The ArcIMS Servlet Connector, included with the ArcIMS product, can be used to administer the ArcIMS Application server and to serve requests from multiple clients, such as HTML Viewer, ArcMap. The Servlet Connector also includes an authentication mechanism to restrict access to MapServices for those users specified in a file or JDBC-based Access Control List (ACL). The ACL can prohibit specific requests from being sent to an ArcIMS service. Unfortunately there is no way to restrict specific portions of the request, therefore all or none of a certain request can be permitted. For example, if the GET_FEATURES request is forbidden in an ACL for a specific ArcIMS service and user, all GET_FEATURES requests sent to that service will be blocked. In short, the Servlet Connector does not provide a mechanism for restricting attributes or child elements of a request.

Procedure

Note:
 This sample is not supported by ESRI 

1. Confirm ArcIMS requirements
   
   Make sure that ArcIMS is functioning correctly. Confirm that an ArcIMS image mapservice is running and an HTML Viewer referencing that mapservice will load successfully in a browser.
   
   
2. Add the Java Connector jars to the servlet engine classpath
   
   All four Java Connector jars must be in the servlet engine's classpath. For Tomcat users, add all jars to the $TOMCAT_HOME\classes directory. Other servlet engines may require you to add the path to each jar specifically.
   
   
3. Unzip the JConnServlet zip file in a new directory
   
   Create a new directory and unzip the contents of the JConnServlet zip file.
   
   
4. Add the JConnServlet Connector classes to the servlet engine
   
   Locate the default servlet directory for your servlet engine. Note that in most cases, the ArcIMS Servlet Connector is located in the default servlet directory. Copy and paste the com folder and the jconnservlet_prop file to the default servlet directory. If you receive a message to "Confirm Folder Replace", click "Yes to All".
   
   
5. Change the ArcIMS Application server and port in the jconnservlet_prop file
   
   Open the jconnservlet_prop file in a text editor. Change the appServerMachine and appServerClientPort to the ArcIMS Application server and connector port, respectively. Save the file.
   
   
6. Restart the servlet engine and web server
   
   
7. Check communication with the JConnServlet Connector
   
   Open a browser and type the following (where "server_name" is your web server's host name):
   
   

   Code:
   http://server_name/servlet/com.esri.custom.JConnServlet?cmd=ConnectorPing

   
   
   You should see the following response:
   
   

   Code:
   JConnServlet 1.0

   
   
8. Check communication between the JConnServlet Connector and the ArcIMS Application server
   
   Open a browser and type the following (where "server_name" is your web server's host name):
   
   

   Code:
   http://server_name/servlet/com.esri.custom.JConnServlet?cmd=AppServerPing

   
   
   You should see the following response:
   
   

   Code:
   SUCCESS: ArcIMS Application Server Contacted Successfully 

   
   
   
   
9. Setup an HTML Viewer to use the JConnServlet Connector
   
   From the HTML Viewer referenced in step 1, open the ArcIMSParam.js (in the website's root directory) file in a text editor. Near the beginning of the file, change the following line from (:
   
   

   Code:
   var esriBlurb = "/servlet/com.esri.esrimap.Esrimap?ServiceName="

   
   
   -to-
   
   

   Code:
   var esriBlurb = "/servlet/com.esri.custom.JConnServlet?ServiceName="

   
   
   Also, change the following lines to reference the JConnServlet Connector accordingly (note that the service name referenced by these lines may be different in your HTML Viewer):
   
   

   Code:
   var imsURL = 'http://server_name/servlet/com.esri.esrimap.Esrimap?ServiceName=World';
   var imsOVURL =  'http://server_name/servlet/com.esri.esrimap.Esrimap?ServiceName=World';

   
   
   -to-
   
   

   Code:
   var imsURL = 'http://server_name/servlet/com.esri.custom.JConnServlet?ServiceName=World';
   var imsOVURL =  'http://server_name/servlet/com.esri.custom.JConnServlet?ServiceName=World';

   
   
   Save the file.
   
   
10. Load the HTML Viewer in a browser
    
    Open a browser and load the HTML Viewer referenced in the previous step. The HTML Viewer should load successfully. The HTML Viewer is now using the JConnServlet Connector instead of the ArcIMS Servlet Connector to communicate with the ArcIMS Application server.
    
    
11. Evaluate ArcIMS security options
    
    The JConnServlet Connector can be deployed in any servlet enabled location on your servlet engine. It will allow you to detect and alter incoming requests at any level (element or attribute) as well as restrict the type of clients accessing your ArcIMS Application server. While the ArcIMS Servlet Connector is needed to administer your ArcIMS site using ArcIMS Administrator, it is not required, and may not be the most functional and\or secure solution for HTML clients. While aliasing the ArcIMS Servlet Connector (see Related Information below) will block most incoming requests from non-HTML clients, it will not necessarily restrict communication with development environments that allow the creation and posting of HTML forms. For example, the Java package java.net contains the URL and URLConnection classes which can be used to send raw ArcXML requests to an ArcIMS Application server through a servlet. In conclusion, the techniques introduced in the JConnServlet Connector can be used to assuredly manage the incoming and outgoing information associated with your ArcIMS site.