Migration tips

When migrating an application from the Genero Desktop Client (GDC) to the Genero Web Client for JavaScript (GWC-JS), you may encounter issues. Here are some tips that may help.

Configuration issues
Rendering issues
Application issues
Network issues
Web Components

Configuration issues

The Genero Application Server (GAS) is likely serving several types of applications, which might use different versions of the Genero Business Development Language and different databases. You need to configure the GAS for the environment your application will be running. This is done through a configuration file.

If you already have your application configured for GDC-HTTP, you need to enable the rendering for GWC-JS.

Example of configuration for a GDC application:

<APPLICATION Id="my-app" Parent="defaultgdc">
  <EXECUTION>
    <PATH>$(res.path.fgldir.demo)</PATH>
    <MODULE>demo.42r</MODULE>
  </EXECUTION>
</APPLICATION>

To allow GWC-JS rendering, replace defaultgdc by defaultgwc, and add the UA_OUTPUT for the public image resources and the GWC-JS customization:

<APPLICATION Id="my-app" Parent="defaultgwc">
  <EXECUTION>
    <PATH>$(res.path.fgldir.demo)</PATH>
    <MODULE>demo.42r</MODULE>
  </EXECUTION>
  <UA_OUTPUT>
    <PUBLIC_IMAGEPATH>$(res.public.resources)</PUBLIC_IMAGEPATH>
    <GWC-JS>gwc-dev</GWC-JS>
  </UA_OUTPUT>
</APPLICATION>

See the Configuring applications on GAS topic to configure your execution environment, the database access and the resource deployment (pictures, reports, and so on).

If the application fails to start:

Look in the dispatcher log for error messages.
Start a debug console as explained in the What if the application doesn't start? topic.
With a console, the GAS does not launch the application, but instead launches a console with the application environment set up. You can then compare the environment variables to your GDC working environment.
With a console started you can run commands to check and update your environment variables.
You can also display the application on the GDC by changing the FGLSERVER environment variable to verify that the application runs properly with GDC.

Rendering issues

Graphical widgets that are not rendered properly or displayed with a different style are considered rendering issues. Try to identify the source of the rendering issue. This could be the browser, your code, or some GWC-JS customization. For help with troubleshooting see Rendering issues.

Application issues

Application issues are behavior related. Most of the time you need to contact your local support center. But you can first check for:

Relevant messages in the logs
JavaScript errors

If clues are provided in either the logs or in the errors, try to build a simple test program that replicates the issue and contact your local support center.

Network issues

Once the migration is almost done and you are in load tests phase, you might encounter sporadic disconnections. Carefully read the chapters on GAS installation for your Web server and verify the Web servers and GAS timeouts are compatible. You can also have a look at:

Web server log (error/access log)
The Genero Application Server logs
Network sniffer (like Wireshark)

Web Components

The default path for a Web component is appdir/webcomponents, where "appdir" is the application directory. See the WEB_COMPONENT_DIRECTORY element in your FGLASDIR/etc/as.xcf configuration file:

<WEB_APPLICATION_EXECUTION_COMPONENT Id="cpn.wa.execution.local">
   […]
   <DVM>$(res.dvm.wa)</DVM>
   <WEB_COMPONENT_DIRECTORY>$(application.path)/webcomponents;
                             $(res.path.as)/webcomponents</WEB_COMPONENT_DIRECTORY>
</WEB_APPLICATION_EXECUTION_COMPONENT>

You can change the default Web components location by configuring a WEB_COMPONENT_DIRECTORY element in your application's configuration. In this example, the Web component is no longer located in appdir/webcomponents but in appdir/mycomponents.

<APPLICATION Parent="defaultgwc" …>
  <EXECUTION>
    <PATH>/home/myapp</PATH>
    <MODULE>myapp</MODULE>
   <WEB_COMPONENT_DIRECTORY>/home/myapp/mycomponents</WEB_COMPONENT_DIRECTORY>
  </EXECUTION>
</APPLICATION>