nsyslog/lib/mingo.js

Modular new generation log agent. Reads, transform, aggregate, correlate and send logs from sources to destinations

const
	mingo = require('mingo'),
	jsexpr = require('jsexpr');

const EV_CACHE = {};
const EX_CACHE = {};

try {
	mingo.addOperators(mingo.OP_QUERY, function(_) {
		return {
		  $starts(selector, value, args) {
				  args = Array.isArray(args)? args : [args];
			return (value||"").startsWith(args[0]);
		  },
			  $startsWith(selector, value, args) {
				  args = Array.isArray(args)? args : [args];
			return (value||"").startsWith(args[0]);
		  },
			  $ends(selector, value, args) {
				  args = Array.isArray(args)? args : [args];
			return (value||"").endsWith(args[0]);
		  },
			  $endsWith(selector, value, args) {
				  args = Array.isArray(args)? args : [args];
			return (value||"").endsWith(args[0]);
		  },
			  $contains(selector, value, args) {
				  args = Array.isArray(args)? args : [args];
			return (value||"").indexOf(args[0])>=0;
		  }
		};
	  });
	  
	  mingo.addOperators(mingo.OP_EXPRESSION, function(_) {
		  return {
			  $eval(selector, value, args) {
				  if(!EV_CACHE[value]) {
					  EV_CACHE[value] = jsexpr.eval(value);
				  }
				  return EV_CACHE[value](selector);
			  },
			  $expr(selector, value, args) {
				  if(!EX_CACHE[value]) {
					  EX_CACHE[value] = jsexpr.expr(value);
				  }
				  return EX_CACHE[value](selector);
			  },
			  $keyval(selector, value, args) {
				  let val = _.computeValue(selector,value);
				  return val.reduce((map,item)=>{
					  map[item[0]] = item[1] || "_";
					  return map;
				  },{});
		  },
			  $trim(selector, value, args) {
				  let chars = new Set((value.chars||'').split(''));
				  let val = _.computeValue(selector,value.input).split('');
				  while(chars.has(val[0])) val.shift();
				  while(chars.has(val[val.length-1])) val.pop();
			return val.join('');
		  },
			  $starts(selector, value, args) {
				  let val = _.computeValue(selector,value[0]);
			return (val||"").startsWith(value[1]);
		  },
			  $startsWidth(selector, value, args) {
				  let val = _.computeValue(selector,value[0]);
			return (val||"").startsWith(value[1]);
		  },
			  $ends(selector, value, args) {
				  let val = _.computeValue(selector,value[0]);
			return (val||"").endsWith(value[1]);
		  },
			  $endsWith(selector, value, args) {
				  let val = _.computeValue(selector,value[0]);
			return (val||"").endsWith(value[1]);
		  },
			  $contains(selector, value, args) {
				  let val = _.computeValue(selector,value[0]);
			return (val||"").indexOf(value[1])>=0;
			  }
		  };
	  });	  
}catch(err) {
	
}


module.exports = mingo;