Page Comparison

Custom Action Setting Config values:

One use case of the feature is to allow custom actions that run before a plugin to set macros. Custom actions can use workflow tokens to set values for field names.  

"plugin": {
	"name": "Database",
	"type": "batchsource",
	"properties": {
		"user": "${wf-token(username)}",
		"password": "${secure(sql-password)}",
		"jdbcPluginName": "jdbc",         
		"importQuery": "select * from ${wf-token(table-name)};"
	}
}

If pipeline builder wants to use a workflow token sent from a preceding custom action to be used as value for fields, then he uses the macro-type token in his fields as above.

Context has access to the workflow token and we should be able to use workflow tokens similar to runtime arguments for substitution.

Scoping:

Scoping will not be implemented but is currently at low priority and can be done manually. In our example config from a JDBC source to a table sink, there is a common macro "${table-name}", if the user wants to provide a different name for the table-name in Table Sink, he can manually do this:

This is more of the user creating unique argument keys as opposed to scoping.

Documentation/Changes

Regardless of where the substitution occurs, the guidelines for creating Hydrator plugins would have to change. For existing plugins, any validation for properties that are macro-substitutable in configurePipeline must be moved to prepareRun (see reference section for specific plugins). We also must document the convention for nulling/defaulting macroable properties at configure time.

Implementation Details

interface MacroContext {	
	/**
	 * Given the macro key, return the substituted value
     */ 
	String getValue(String macroKey);
}

Based on the macro type, one of the below MacroContext's will be used to get the value for macro. 
 
DefaultMacroContext implements MacroContext {
	Map<String, String> runtimeArguments;
	String getValue(String macroKey) {
		return runtimeArguments.get(macroKey);
	}
}

SecureMacroContext implements MacroContext {
	SecureStore secureStore;
	String getValue(String macroKey) {
		return secureStore.get(macroKey);
	}
}

RuntimeFunctionMacro implements MacroContext {	
	long logicalStartTime;
	Function<String, String> timezoneFunction;
	String getValue(String arguments) {
		return timezoneFunction.apply(arguments);
	}
}