This topic explains how to configure message proxies that send and receive messages over HTTP (including HTTPS). 

In this section: 

Before you set basic HTTP connection options, you need to know the host, port, and path of the service for which you want to create a proxy. These are the settings you would normally use to directly message the service. 

Connection Settings

To specify basic HTTP connection options, set the following service and listening details in the Proxy Settings Connection tab.

Proxy Settings (incoming) 

These settings specify where messages from the client should connect to Virtualize in order to communicate with the application under test. 

SSL Settings for Listener Ports

Enable the Use keystore option to configure server side SSL settings.

Configure the following settings:

Enable the Perform client authentication option to configure client side SSL settings.

Configure the following settings:

Primary Connection (outgoing)

Secondary Connection (outgoing)

Enable the Use secondary connection if primary fails option if you want traffic to be redirected to a secondary proxy endpoint when the primary connection fails or the responder is not available. The connection will be considered "failed" if the response status code is 400 level or higher.

For instance, you might want to specify a secondary endpoint if you want a virtual asset to be used whenever the live endpoint is unavailable. Or, if a virtual asset does not handle a given use case, you could use a secondary endpoint to have that traffic redirected to the live endpoint. You could then optionally record that live traffic for creating a new virtual asset to cover that use case.

If this option is not enabled, the primary connection will be used for recording.

If this option is enabled, you can select from the available recording options (described below).

Recording options

These settings determine how to record traffic when a secondary endpoint is specified.

• Record on both connections: Records traffic for both the primary and secondary connections. Error messages from the primary will not be recorded; instead the messages will be sent to the secondary and the responses will be recorded. Errors reported by the secondary will be recorded.
• Record on primary connection only: Records traffic for the primary connection. Does not record errors.
• Record on secondary connection only: Records traffic for the secondary connection, including errors.

Security Tab Settings

The Service SSL section needs to be completed only if the service you are virtualizing uses SSL.

If the service being virtualized and/or the application under test use SSL and/or other authentication (basic/digest, Kerberos, NTLM), additional configuration may be required.

For details on completing the Service SSL fields immediately below these fields, see Security Configuration.

Proxy Server Tab Settings

This tab lets you specify a proxy server at the Virtualize message proxy level—so you can control which proxy server handles traffic between the application under test and a specific Virtualize message proxy. This allows you to configure different proxy servers for traffic to and from different Virtualize message proxies. 

To specify proxy settings at this level, provide the appropriate details in the proxy’s Proxy Server tab. 

SSL is not supported. 

Service Forward Path and Proxy Listen Path

In the simplest case, you can set Proxy listen path to the path of your service and leave Service forward path empty. With this configuration, the proxy will automatically forward all messages it receives on that path to the same path at the Service host and Service port. 

If you need the proxy to listen on a different path than the path of your service, set Service forward path to the actual path where you want received messages to be sent. The proxy will forward the path and any query parts to the target service. 

If the Proxy listen path and the Service forward path are different, then any segments in the request after the Proxy listen path will be appended to the forwarded request. The Proxy listen path is essentially being replaced with the Service forward path so that the entire path (as received by the proxy) gets sent to the service.

Using Wildcard Characters in Paths

Wildcard characters can be used to specify dynamic path segments. For example, assume two requests were sent to Virtualize on the paths /path/1/service and /path/2/service. To have both requests go to the same proxy, configure the path as /path/*/service. 

Wildcards can be used to replace an entire path segment. For example:

• /path/*/service — valid
• /path/1*2/service — not valid

Note that /path/*/service will NOT match /path/1/2/service. If you want your path to match both /path/1/2/service and /path/3/4/service, use the pattern /path/*/*/service.

You can use the dynamic segment from the listen path as part of the forward path. There are two ways to do this:

• If you want traffic to be forwarded to the path where the request was received, leave the forward path empty.

• If the forward path is different and the dynamic value needs to be used, configure it using environment variable syntax. For example:
  listen path: /path/*/service
forward path: /asset/path/${1}/service

The dynamic listen path segments represented by the wildcards can be accessed using environment variable syntax. The occurrence of the wildcard is used as the variable name; in other words, the first occurrence of the wildcard is ${1}, the second is ${2}, the third is ${3}, etc.  In the following example, ${2} refers to the second occurrence of the wildcard (which was "bank" in the request path):

listen path: /path/*/service/*/account
forward path: /asset/path/${2}/service/${1}/account

request path: /path/1/service/bank/account
forward path: /asset/path/bank/service/1/account

Header Alterations

In most cases, the proxy will pass all headers directly to and from the target service. Some content-length related headers may be changed to suit how the proxy server works. For example, the proxy server doesn't support responding with the "chunked" transfer encoding and will replace "host" headers sent to match its own host name (however, it does support receiving chunked requests and chunked responses from the target service).

Pointing to Virtual Assets or Actual Services

A proxy can use a virtual asset on a Virtualize Server as its target service. To do this:

1. Set the service host and port to that of the Virtualize Server where the virtual asset is deployed. If you want the proxy to foward to a virtual asset on the local Virtualize server without consuming an HTTP connection, enter localhost or 127.0.0.1 rather than the actual host name.
2. Set the proxy connection’s Service forward path to the virtual asset’s path (found in the virtual asset’s Transports> HTTP tab, under HTTP endpoint).
   
   

Chunking/Unchunking Behavior

The proxy supports receiving chunked requests and chunked responses from the target service. If a service response uses HTTP chunking, proxies will unchunk responses before they are returned to the original caller/AUT.

Additional HTTP Message Proxy Configuration

You can create a properties file to configure additional HTTP listener settings. The properties file allows you to fine-tune HTTP listener performance and specify additional SSL settings.

1. Create a plain text file and specify the properties you want to set (see HTTP Listener Message Proxy Performance Properties and HTTP Listener Message Proxy SSL Properties). 
2. Save the file to the VirtualAssets directory in your workspace and name it embeddedServer.properties.

The file will be read every time a proxy with HTTP listeners is enabled.

HTTP Listener Message Proxy Performance Properties

All properties are optional and non-integer values will be ignored.

HTTP Listener Message Proxy SSL Properties

Example: Sending Traffic to a Service

Assume that we want to create a message for a service that is normally accessed at http://example.parasoft.com:9080/BookStore. We could create an HTTP proxy with the settings: 

• Proxy listen path: /BookStore
• Service host:example.parasoft.com
• Service port: 9080
• Service forward path: [empty]
  
  

This configuration will listen on /BookStore and forward all traffic to the actual book store service.

If we wanted to listen on a path other than the service path, we would configure the proxy as follows:

• Service forward path: /BookStore
• Proxy listen path: /SomeOtherPath
  
  

This would route traffic from /SomeOtherPath on the proxy to the actual book store service. 

In both cases, all traffic that goes to those paths (including sub paths) is sent to the service. In the second example, traffic sent to /SomeOtherPath/SubPath would be sent to /BookStore/SubPath. Since queries are preserved, /SomeOtherPath?param=value would be sent to /BookStore?param=value.

Forwarding Requests to Services that Require Case-sensitive Header Names

If you are using the Virtualize desktop's server, your message proxy headers will be lowercased and may fail to function properly when requests are forwarded to a service that requires case-sensitive HTTP header names.

You can create a _global.headers file in the /VirtualAssets/ directory and add the headers using the specific capitalization you want to pass. Right-click the server in the UI and re-deploy all virtual assets to begin using this file in your environment.

You can also address HTTP header capitalization issues for specific message proxies. Create a <proxy-name>.headers file in the /VirtualAssets/ directory and add the headers using the specific capitalization you want to pass for the specific proxy. This file will apply to specific proxy and override the global file. Right-click the server in the UI and re-deploy all virtual assets to begin using this file in your environment.

Example Headers File

X-AUTHORIZATION
ANOTHER-HEADER
HEADER3

Example: Sending Traffic to a Virtual Asset

A proxy can also send traffic to a virtual asset. In that case, enter the host and port information for the Virtualize Server as if were just another service.

For example, to send traffic to a virtual asset on a remote server, you might use: 

• Service host: virtualize.parasoft.com
• Service port: 9080
• Proxy listen path: /path
  
  

To send traffic to a virtual asset on a local server, you might use:

• Service host: localhost
• Service port: 9080
• Service forward path: /pva
  
  

The HTTP proxy makes no distinction between a virtual asset and an actual service. Both are configured the same way. However if the HTTP proxy is sending to localhost, you must specify Service forward path because the proxy doesn't allow forwarding to itself.

Security Configuration

There are two aspects of configuration for security: 

• If the service to which you are forwarding the traffic uses SSL and/or access authentication, you need to perform Proxy-Level Configuration (from the proxy’s UI controls).
• If the AUT uses SSL and/or access authentication, you need to perform Server-Level Configuration (for the Tomcat-based Virtualize Server).

Thus, depending on your configuration, you might perform server-level configuration, proxy-level configuration, or both.

Proxy-Level Configuration

Proxy-level security configuration—which is relevant if the service to which you are forwarding the traffic uses SSL and/or access authentication—covers:

• SSL
• Basic/Digest Authentication
• NTLM Authentication
• Kerberos Authentication

SSL

For SSL, additional settings are required. In the lower part of the configuration panel, you need to specify whether to:

• Enable trust for self signed certificates.
• Enable trust for all certificate.
• Set a trust store to validate server certificates.

Additionally, you need to provide the information needed to use a specific key store and certificate so Virtualize can determine which certificate to present to a server (e.g., for 2-way SSL).

SSL Configuration Panel Fields

Note that the Truststore configuration (described below) is applicable only if Trust all server certificates and Accept self-signed certificates are both unselected.

Keystore Configuration Panel Fields

After completing the keystore detail, click the Load button. Then, from the Certificate drop-down, select the certificate alias for Virtualize to present to the server. If the Certificate dropdown is not populated when you click Load, you may have entered the incorrect password or keystore type.

Truststore Configuration Panel Fields

These fields are applicable only if Trust all and Accept self-signed certificates (described above) are both unselected.

NTLM Settings Panel Fields

Kerberos Panel Fields

Basic/Digest Authentication

If the application under test provides Basic and Digest authentication credentials as part of the request and transmits them as part of the HTTP header, the proxy will pass them along to the service unmodified (the same way it handles other HTTP headers). 

NTLM Authentication

If your service requires NTLM authentication, provide the username/password in the NTLM section.

Kerberos Authentication

If your service requires Kerberos authentication, set the Kerberos Service Principal in the Kerberos Authentication section.

Server-Level Configuration

Server-level security configuration—which is relevant if the AUT uses SSL and/or access authentication—can involve:

• Configuring the Virtualize Server
• Using NTLM with WAFFLE
• Using Unsupported Configurations (Kerberos with WAFFLE, JAAS)

Configuring the Virtualize Server

The Virtualize Server uses port 9080 by default. If you want to change the proxy port (e.g., to improve security by moving the server off common/well-known ports), see Using an Alternative Port for the Virtualize HTTP Server.

If the AUT uses SSL, you need to configure the Virtualize Server as described in Configuring SSL (HTTPS) for the Virtualize Server. 

Using NTLM with WAFFLE

To use the third-party library WAFFLE for NTLM:

1. Copy the following jar files into tomcat's lib directory: jna.jar, platform.jar, wafflejna.jar.

2. Add the following to tomcat/conf/server.xml.
   
   

   <Context>
     <Valve className="waffle.apache.NegotiateAuthenticator" principalFormat="fqn" roleFormat="both"/> 
     <Realm className="waffle.apache.WindowsRealm" /> </Context> 

   Where is server.xml?

   - If you installed Virtualize but not SOAtest: Launch Virtualize, ensure that at least one responder has been created, then modify the server.xml file at [Virtualize install dir]/eclipse/plugins/com.parasoft.xtest.libs.web_[Virtualize_ver]/root/tomcat/conf/server.xml

   - If you installed Virtualize and SOAtest together: Launch Virtualize, ensure that at least one responder has been created, then modify the server.xml file at [SOAtest install dir]/eclipse/plugins/com.parasoft.xtest.libs.web_[SOAtest_ver]/root/tomcat/conf/server.xml

3. Add the following to tomcat/conf/web.xml.

   <security-role> 
     <role-name>Everyone</role-name> 
   </security-role> 
   <security-constraint> 
     <display-name>Waffle Security Constraint</display-name> 
     <web-resource-collection> 
       <web-resource-name>Protected Area</web-resource-name> 
       <url-pattern>/*</url-pattern> 
     </web-resource-collection> 
     <auth-constraint> 
       <role-name>Everyone</role-name> 
     </auth-constraint> 
   </security-constraint> 

4. Restart the server.

For more details, see the Single Sign-On: Tomcat Negotiate Authenticator (Kerberos + NTLM) w/ Waffle Tutorial and the WAFFLE home page.

Using Unsupported Configurations (Kerberos with WAFFLE, JAAS)

WAFFLE includes support for Kerberos authentication; see the WAFFLE home page for directions and support. 

JAAS is another option for configuring the Tomcat-based Virtualize Server to perform Kerberos authentication. Consult Tomcat for directions on how to use JAAS.

Video Tutorial: Configuring an HTTP Message Proxy

This video describes how to set up a message proxy that can capture live traffic.