modInput_1.js

//modinput.js
//A few prototypes namely Arg and Event are introduced to make the code more readable, toolable (syntax completion in editors/ides)
//and less error prone. 
var splunk = require('splunk-sdk');
var mod = splunk.modularInput;
var logger = mod.logger;
 
// logger.info(..);
// logger.error(..);

// lifecycle events
mod.on("init", function(done) { 
    // Before any stream events have been called
});
 
mod.on("complete", function(done) {
    // After all stream events have been called
});
 
mod.on("teardown", function(done) {
    // After all done() calls are done
});

 
exports.getScheme = function() {
  var scheme = new {
    name: 'Random Numbers',
    desc: 'Streams events containing a random number'
    args: [
      {name:'min', desc:'Minimum random number to be produced by this input.', type:DataType.number, requiredOnCreate:true},
      {name:'max', desc:'Maximum random number to be produced by this input.', type:DataType.number, requiredOnCreate:true}
    ]
    
    //can also be done with an object
    //
    // var args = [];
    // var arg = new Arg();
    // arg.name = 'min';
    // arg.desc = 'Minimum random number to be produced by this input.';
    // arg.type = DataType.number;
    // arg.requiredOnCreate = true;
    // args.push(arg);
  };
  return scheme;
}
 
exports.validateInput(definition, done) {
  var min = parseFloat(definition.min);
  var max = parseFloat(defintiion.max);
  
  if (min < max) {
    throw sprintf('min must be less than max; found min=%f, max=%f', min, max);
  }
    
  done();
}
 
//We will invoke this for each input so a developer does not have to write boilerplate looping code.
//they can check the inputName if they are supporting multiple instances.
exports.streamEvents = function(name, definition, writer, done) {
  var min = parseFloat(definition.min);
  var max = parseFloat(definition.max);
 
  //Event contains a convenience constructor with the most common properties, addl props can be set on the object.  
  var event = new {name:name,data:sprintf('number=%s', Math.floor((Math.random()*max)+min)), sourecetype:'random_numbers');
 
  //the writer is a node Writeable stream
  writer.write(event);
  
  // IDEA
  // logger.getLogger(name).error("foo")
  
  //Once data is no longer received the user calls the done callback. 
  //If this input is continually streaming in results, then this will not get called.
  done();
}

splunk.modularInput.execute(exports, module); //passing the module allows checking if this is the entry process