move database helpers into their own files

src/database/mongo/helpers.js

@@ -0,0 +1,52 @@
+"use strict";
+
+var helpers = {};
+
+helpers.findItem = function(data, key) {
+	if(!data) {
+		return null;
+	}
+
+	for(var i=0; i<data.length; ++i) {
+		if(data[i]._key === key) {
+			var item = data.splice(i, 1);
+			if(item && item.length) {
+				return item[0];
+			} else {
+				return null;
+			}
+		}
+	}
+	return null;
+};
+
+helpers.fieldToString = function(field) {
+	if(field === null || field === undefined) {
+		return field;
+	}
+
+	if(typeof field !== 'string') {
+		field = field.toString();
+	}
+	// if there is a '.' in the field name it inserts subdocument in mongo, replace '.'s with \uff0E
+	field = field.replace(/\./g, '\uff0E');
+	return field;
+};
+
+helpers.valueToString = function(value) {
+	if(value === null || value === undefined) {
+		return value;
+	}
+
+	return value.toString();
+};
+
+helpers.done = function(cb) {
+	return function(err, result) {
+		if (typeof cb === 'function') {
+			cb(err, result);
+		}
+	};
+};
+
+module.exports = helpers;