Troubleshooting

There could be several reasons for this issue. Some of those are:

• Ensure that all the Canvas schema scripts have been executed successfully. The scripts are dependent on the credentials given in the ‘config.txt’ file.
• Connect to each Canvas schema (MODEL, EXPERT, and WIZARD) in the Oracle SQL Developer and check if you are able to view the tables.
• Ensure the correct schema name and password, port number, and Oracle SID are specified in the respective app/web server configuration. Such configurations in Tomcat server are in the 'server.xml' that is located in the Tomcat folder, e.g. D:\Canvas\apache-tomcat-7.0.67\conf\server.xml.
  
  
  
  
• Stop and restart the Tomcat server and check if you are able to connect to Canvas applications.

Perform the following steps:

1. Logout of the application and log-on again to see if the new changes are visible.

2. If not, clear the cache using the following URL in the address bar of the browser:

   http://<hostname>:<port number>/expertctstudio/cacheReset.jsp
   
   # For example,
   http://localhost:9080/expertctstudio/cacheReset.jsp

3. Clear the cookies and history in the browser.
4. Stop and restart the web/app server.
5. Access the application. You must be able to view the changes done in Canvas Studio.

Scenario: I created a grid view configured with a SQL Map and default instruction class. I had mapped the view to an app, which in turn is mapped to a workspace. However, in the application (e.g. CT ModelHouse), the app (widget) is empty and does not display any data even though the table that is referred in the SQL Map does contain data.

Try all of the following steps:

• Ensure that the SQL Map ID is correct in the configuration screens in Canvas Studio as defined in the SQL XML file.
• Ensure minimum one column from the table is selected as a sortable indicator in the configuration for the view in Canvas Studio.
• Ensure that the view items ID (columns) of the grid in the Canvas Studio configuration screen are exactly the same as the column names in the table.
  
  
  
  

• Ensure that the column names and table names in the SQL Map query are the same as in the database schema.

  If you are using Data Source instead of SQL Map, ensure that the column names and table name given in the Data Source configuration screen in Canvas Studio are same as in the database schema.

  
  

• If all the above fails, clear the cache for Canvas Studio and the application. Clear the browser cookies. Access the application to check if the widget is displayed with the data from the table.

1. Check for exceptions in server and db log and act on it. 
2. Check if there is entry for the application in APPLICATION_MASTER table.
   
   In Canvas 20.x.x.x, the entry for Application ID should be available in both CanvasApplicationContext.json as well as in APPLICATION_MASTER.

Following error patterns can be ignored:

[com.intellectdesign.canvas.validator.ValidationXMLParser][ERROR]
	 {[CTVAL00045]:Caught Exception in ParserWrapper.java. Method: 
		public ArrayList validateMessage(String $vType, String $fileName) throws ValidationException}
com.intellectdesign.canvas.exceptions.common.BaseException: 
		The resource provided 'SOME_PATH/req_modelerform_REQUEST_MODEL_ID_APPLICATION_PATH.xml' cannot be loaded 
		from classpath as well as file system

CTFDF00035 [com.intellectdesign.canvas.formdefinition.handler.PictureProcessHandler][ERROR]
	 {[CTFDF00035]:Error while Reading from file 'Default.png'}

CTRND00433 [com.intellectdesign.canvas.syncaction.SyncActionHelper][ERROR]
	 {[CTRND00433]:A Base Exception for moduleID 'SOME_MODULE_ID' for action 'SYNC_METADATA'.
		 This may be ignored as applications can choose to skip certain modules.}

java.util.ConcurrentModificationException
	at java.util.ArrayList.sort(ArrayList.java:1464)
	at java.util.Collections.sort(Collections.java:175)
	at com.intellectdesign.canvas.viewdefinition.ViewDefinition.getViewDefinitionAsMap(ViewDefinition.java:168)

To turn off the scheduler when the reporting capability in CT Platform is not needed, remove the value of the CT_INFO_REPORT_BUNDLE key in the CT configuration file (.properties file) inside the application WAR.