Cnxml Configuration File

The external adapter framework defines the structure of the cnxml file that contains the adapter properties.

The external adapter configuration file is an XML file that contains the properties and commands used by Event Stream Processor to start and stop the external adapter, and to optionally run schema discovery, as well as other information that allows you to configure the adapter from Studio.

Here is the structure of a cnxml file:

<Adapter> 
	type = Can be input or output
	external = True
	id = Required to be unique to the adapter
	label = The adapter's name in Studio
	descr = Description of adapter functionalities

<Library>
	file = simple_ext (Always use this for custom external adapters)
	type = Binary

<Special>
	<Internal>
		**These values are not configurable from Studio. simple_ext has a function that parses this cnxml file and looks up the internal fields to find particular commands and their default values**
	id = See $STREAMING_HOME/lib/adapters/simple_ext.cnxml.template for a sample cnxml file that contains all possible internal parameters and comment blocks indicating their usage.
	label = Description of function
	type = Datatype of function
	default = This is the command that simple_ext executes. For example, if you are using x_unixCmdExec, it calls streamingconvert with targets you specify followed by an upload.

<Section>
	<Parameter>
	**These parameter values are visible (except for id) and configurable in Studio.** 
	     id = The property id that you can reference to in <Internal> command calls with $(id's name). This is what you reference when writing an adapter in CCL.
		label = The property name which appears in Studio.
		descr = Description of adapter property.
		type = The property datatype.
		use = Whether the property is required, optional, or advanced. In Studio, required properties appear in red and advanced ones appear on a separate tab.
		default = Default value to use, if you do not set a value for the property.