feat: Use custom errors

Author: rauno56

lib/zabbix.js

@@ -1,4 +1,5 @@
 var request = require('request');
+var ZabbixError = require('./ZabbixError');
 
 var Client = function (url, user, password) {
   this.url = url;
@@ -38,15 +39,15 @@ Client.prototype.call = function call(method, params, callback) {
       result = JSON.parse(body);
       callback(null, response, result);
     } else if (response.statusCode == 412) {
-      callback(new Error('Invalid parameters.'), response, body);
+      callback(new ZabbixError('Invalid parameters.'), response, body);
     } else {
       // 1.9.6 just returns a empty response with Content-Length 0 if the method does not exist.
       // 2.x returns a proper response!
       if (this.apiversion == '1.2') {
-        callback(new Error('That method does most likely not exist.'), response, 'Method missing!');
+        callback(new ZabbixError('That method does most likely not exist.'), response, 'Method missing!');
       } else {
         // If we get here something else is broken, we should look into this more and handle more special cases (in a general way).
-        callback(new Error('Something else went wrong'), response, body);
+        callback(new ZabbixError('Something else went wrong'), response, body);
       }
 
     }