It depends; if you are building data pipelines using the available plugins, then no. But if you want to implement a custom plugin, then you need to have knowledge of Java and the relevant CDAP APIs.
It's part of the CDAP Sandbox.
Customers have CDAP running in AWS, GCE, and Azure.
CDAP has an open source support system. It has a Google group where developers and users can ask questions, available at cdap-user@googlegroups.com.
You can use the open source JIRA system for CDAP, CDAP pipelines, and other projects. If you have a commercial CDAP subscription, the Cask support portal is available for customers to report issues.
CDAP is an open source project licensed under the Apache 2.0 license, though not currently part of the Apache Foundation. In order to contribute to CDAP, you may need to provide to Cask a signed ICLA or CCLA. The terms are open and very similar to the Apache Foundation. Contact Cask through the cdap-user@googlegroups.com for more information.
You can file a JIRA ticket for the feature request or, if you have a commercial CDAP subscription, you can use the support portal.
Error parsing widgets JSON for the plugin <plugin-name>
This error means the widget JSON file for the particular plugin has an error in its JSON, such as:
You are missing a comma character (,
) in the JSON
You have a missing a double quote character ("
) in the JSON
You have a value for a key that is not a valid JSON value (for instance, NaN
)
One way to fix these issues is to use json-lint
to identify problems and make sure the widget JSON is valid.
No widgets JSON found for the plugin <plugin-name>
This error means that the CDAP UI Service could not find the widget JSON for the plugin that you are currently working with. As part of plugin deployment, a JAR and a JSON file are deployed with a plugin, as described in the Packaging Plugins.
The properties are specified as a list inside the configuration groups. Properties of the plugin will appear inside the group in the same order as they are listed.
The CDAP Studio UI will create a separate group named 'Generic', add all properties as part of that group, and (by default) display all properties in a textbox widget.
In a case where the Widget JSON includes a non-existent (or unknown) widget, the CDAP Studio UI defaults to a textbox field.
If you are not seeing the correct widget or the correct default value set in your widget's JSON file, check all the spelling of properties and their values in the widget JSON file.
In particular, check that all values of the properties widget-type
and widget-attributes
are spelled correctly. As these values are case-sensitive, errors can easily be made that can be hard to uncover in the UI itself.