curl_jolokia plugin¶

See this section in the full configuration reference

The curl_jolokia plugin collects values from MBeanServevr - servlet engines equipped with the jolokia (https://jolokia.org) MBean. It sends a pre-configured JSON-Postbody to the servlet via HTTP commanding the jolokia Bean to reply with a singe JSON equipped with all JMX counters requested. By reducing TCP roundtrips in comparison to conventional JMX clients that query one value via tcp at a time, it can return hundrets of values in one roundtrip. Moreof - no java binding is required in collectd to do so.

It uses libyajl (https://lloyd.github.io/yajl/) to parse the Jolokia JSON reply retrieved via libcurl (http://curl.haxx.se/)

<Plugin curl_jolokia>
  <URL "http://10.10.10.10:7101/jolokia-war-1.2.0/?ignoreErrors=true&canonicalNaming=false";>
    Host "_APPPERF_JMX"
    User "webloginname"
    Password "passvoid"
    Post <JOLOKIA json post data>

 <BeanName "PS_Scavenge">
      MBean "java.lang:name=PS Scavenge,type=GarbageCollector"
      BeanNameSpace "java_lang"
      <AttributeName "collectiontime" >
             Attribute "CollectionTime"
             type "gauge"
      </AttributeName>
      <AttributeName "collectioncount" >
             Attribute "CollectionCount"
             type "gauge"
      </AttributeName>
 </BeanName>
</Plugin>

The plugin is intended to be written in a simple manner. Thus it doesn't try to solve the task of generating the jolokia post data, or automatically map the values, but rather leans on a verbose config containing the prepared flat JSON post data and a config section per gauge transformed (as one sample shown above). However, Jolokia can output all available gauges, and we have a python script to filter them, and generate a configuration for you:

jolokia_2_collectcfg.py

it can gather all interesting gauges, write a simple one value per line config for itself and subsequent calls. You can remove lines from this file manually, or create filter lists. You then use the script to generate a collectd config. The script can then inspect data files from some testruns, and remove all gauges, that don't contain any movement.

The base config looks like this:

The following options are valid within URL blocks:

Host Name

Use Name as the host name when submitting values. Defaults to the global host name setting.

Plugin Plugin

Use Plugin as the plugin name when submitting values. Defaults to curl_jolokia.

Instance Instance

Sets the plugin instance to Instance.

Interval Interval

Sets the interval (in seconds) in which the values will be collected from this URL. By default the global Interval setting will be used.

User Name

Password Password

Digest true|false

VerifyPeer true|false

VerifyHost true|false

CACert file

Header Header

Post Body

Timeout Milliseconds

These options behave exactly equivalent to the appropriate options of the cURL plugin. Please see there for a detailed description.

<BeanNameE<gt>

One BeanName block configures the translation of the gauges of one bean to their respective collectd names, where BeanName sets the main name.

MBean MBean

The name of the Bean on the server

BeanNameSpace BeanNameSpace

The name space the Bean resides under

AttributeName AttributeName

A bean can contain several Attributes with gauges. Each one can be matched by a AttributeName section or be ignored.

Attribute Attribute

How should this attribute be called under the BeanName in the collectd hierarchy?

Type Type

Sets the type used to dispatch the values to the daemon. Detailed information about types and their configuration can be found in types.db(5). This option is mandatory.