Table of Contents

Additional JavaScript objects

Additional JavaScript objects

Overview

This section describes Zabbix additions to the JavaScript language implemented with Duktape and supported global JavaScript functions.

Built-in objects

Zabbix

The Zabbix object provides interaction with the internal Zabbix functionality.

Method	Description
`log(loglevel, message)`	Writes <message> into Zabbix log using <loglevel> log level (see configuration file DebugLevel parameter).

Example:

Zabbix.log(3, "this is a log entry written with 'Warning' log level")

You may use the following aliases:

Alias	Alias to
console.log(object)	Zabbix.log(4, JSON.stringify(object))
console.warn(object)	Zabbix.log(3, JSON.stringify(object))
console.error(object)	Zabbix.log(2, JSON.stringify(object))

Method	Description
`sleep(delay)`	Delay JavaScript execution by `delay` milliseconds. This method is supported since Zabbix 5.4.10.

Example (delay execution by 15 seconds):

Zabbix.sleep(15000)

HttpRequest

This object encapsulates cURL handle allowing to make simple HTTP requests. Errors are thrown as exceptions.

HttpRequest is a new name for this object since Zabbix 5.4. Previously it used to be called CurlHttpRequest. Method names are also new in Zabbix 5.4. The old object/method names are now deprecated and their support will be discontinued after Zabbix 6.0.

Method	Description
`addHeader(name, value)`	Adds HTTP header field. This field is used for all following requests until cleared with the clearHeader() method.
`clearHeader()`	Clears HTTP header. If no header fields are set, HttpRequest will set Content-Type to application/json if the data being posted is JSON-formatted; text/plain otherwise.
`getHeaders(<asArray>)`	Returns the object of received HTTP header fields. The `asArray` parameter (supported since Zabbix 5.4.9) may be set to "true" (e.g. `getHeaders(true)`), "false" or be undefined. If set to "true" the received HTTP header field values will be returned as arrays; this should be used to retrieve the field values of multiple same-name headers. If not set or set to "false", the received HTTP header field values will be returned as strings.
`get(url, data)`	Sends HTTP GET request to the URL with optional data payload and returns the response.
`put(url, data)`	Sends HTTP PUT request to the URL with optional data payload and returns the response.
`post(url, data)`	Sends HTTP POST request to the URL with optional data payload and returns the response.
`delete(url, data)`	Sends HTTP DELETE request to the URL with optional data payload and returns the response.
`getStatus()`	Returns the status code of the last HTTP request.
`setProxy(proxy)`	Sets HTTP proxy to "proxy" value. If this parameter is empty then no proxy is used.
`setHttpAuth(bitmask, username, password)`	Sets enabled HTTP authentication methods (HTTPAUTH_BASIC, HTTPAUTH_DIGEST, HTTPAUTH_NEGOTIATE, HTTPAUTH_NTLM, HTTPAUTH_NONE) in the 'bitmask' parameter. The HTTPAUTH_NONE flag allows to disable HTTP authentication. Examples: `request.setHttpAuth(HTTPAUTH_NTLM \\| HTTPAUTH_BASIC, username, password)` `request.setHttpAuth(HTTPAUTH_NONE)`

Example:

try {
           Zabbix.log(4, 'jira webhook script value='+value);
         
           var result = {
               'tags': {
                   'endpoint': 'jira'
               }
           },
           params = JSON.parse(value),
           req = new HttpRequest(),
           fields = {},
           resp;
         
           req.addHeader('Content-Type: application/json');
           req.addHeader('Authorization: Basic '+params.authentication);
         
           fields.summary = params.summary;
           fields.description = params.description;
           fields.project = {"key": params.project_key};
           fields.issuetype = {"id": params.issue_id};
           resp = req.post('https://tsupport.zabbix.lan/rest/api/2/issue/',
               JSON.stringify({"fields": fields})
           );
         
           if (req.getStatus() != 201) {
               throw 'Response code: '+req.getStatus();
           }
         
           resp = JSON.parse(resp);
           result.tags.issue_id = resp.id;
           result.tags.issue_key = resp.key;
       } catch (error) {
           Zabbix.log(4, 'jira issue creation failed json : '+JSON.stringify({"fields": fields}));
           Zabbix.log(4, 'jira issue creation failed : '+error);
         
           result = {};
       }
         
       return JSON.stringify(result);

XML

The XML object allows the processing of XML data in the item and low-level discovery preprocessing and webhooks.

In order to use XML object, server/proxy must be compiled with libxml2 support.

Method	Description
`XML.query(expression, data)`	Retrieves node content using XPath. Returns null if node is not found. expression - an XPath expression; data - XML data as a string.
`XML.toJson(data)`	Converts data in XML format to JSON.
`XML.fromJson(object)`	Converts data in JSON format to XML.

Example:

Input:

<menu>
           <food type = "breakfast">
               <name>Chocolate</name>
               <price>$5.95</price>
               <description></description>
               <calories>650</calories>
           </food>
       </menu>

Output:

{
           "menu": {
               "food": {
                   "@type": "breakfast",
                   "name": "Chocolate",
                   "price": "$5.95",
                   "description": null,
                   "calories": "650"
               }
           }
       }

Serialization rules

XML to JSON conversion will be processed according to the following rules (for JSON to XML conversions reversed rules are applied):

1. XML attributes will be converted to keys that have their names prepended with '@'.

Example:

Input:

 <xml foo="FOO">
          <bar>
            <baz>BAZ</baz>
          </bar>
        </xml>

Output:

 {
          "xml": {
            "@foo": "FOO",
            "bar": {
              "baz": "BAZ"
            }
          }
        }

2. Self-closing elements (<foo/>) will be converted as having 'null' value.

Example:

Input:

<xml>
         <foo/>
       </xml>

Output:

{
         "xml": {
           "foo": null
         }
       }

3. Empty attributes (with "" value) will be converted as having empty string ('') value.

Example:

Input:

<xml>
         <foo bar="" />
       </xml>

Output:

{
         "xml": {
           "foo": {
             "@bar": ""
           }
         }
       }

4. Multiple child nodes with the same element name will be converted to a single key that has an array of values as its value.

Example:

Input:

<xml>
         <foo>BAR</foo>
         <foo>BAZ</foo>
         <foo>QUX</foo>
       </xml>

Output:

{
         "xml": {
           "foo": ["BAR", "BAZ", "QUX"]
         }
       }

5. If a text element has no attributes and no children, it will be converted as a string.

Example:

Input:

<xml>
           <foo>BAZ</foo>
       </xml>

Output:

{
         "xml": {
           "foo": "BAZ"
          }
       }

6. If a text element has no children, but has attributes: text content will be converted to an element with the key '#text' and content as a value; attributes will be converted as described in the serialization rule 1.

Example:

Input:

<xml>
         <foo bar="BAR">
           BAZ
         </foo>
       </xml>

Output:

{
         "xml": {
           "foo": {
             "@bar": "BAR",
             "#text": "BAZ"
           }
         }
       }

Global JavaScript functions

Additional global JavaScript functions have been implemented with Duktape:

btoa(string) - encodes string to base64 string
atob(base64_string) - decodes base64 string

try {
           b64 = btoa("utf8 string");
           utf8 = atob(b64);
       } 
       catch (error) {
           return {'error.name' : error.name, 'error.message' : error.message}
       }

md5(string) - calculates the MD5 hash of a string
sha256(string) - calculates the SHA256 hash of a string

Documentation

Additional JavaScript objects

Overview

Built-in objects

Zabbix

HttpRequest

XML

Serialization rules

Global JavaScript functions