Customize JMX extensions

JMX extensions are defined by JSON files.

An extension definition consists of three main elements: metadata, metrics, and UI.

The basic format is as follows:
  {
    "version": "1.0",
    "name": "custom.jmx.hornetq",
    "type": "JMX",
    "entity": "PROCESS_GROUP_INSTANCE",
    "metricGroup": "tech.HornetQ",
    "configUI" : {
      "displayName": "HornetQ JMX"
    },
    "metrics": [ ],
    "ui": {
      "keycharts" : [ ],
      "charts": [ ]
    }
  }

Metadata

Each JMX extension has the following mandatory properties:

Field
Type
Description
version
String
The extension version, in format d.dd, must be updated whenever the extension definition is updated
name
String
A unique extension name in Java package format. Custom JMX extension names should follow the custom.jmx.name rule. You can only user letters, numbers, and "-", "_" characters. For example, custom.jmx.newPlugin-Ver2
type
String
Always use JMX
entity
String
Always use PROCESS_GROUP_INSTANCE
metricGroup
String
Metric group is used for grouping custom metrics into a hierarchical namespace where different sources, for example multiple extensions, can contribute. Moreover, the metric group becomes a primary part of the metric key. Hence, once defined, it can't be changed. Allowed characters are letters, numbers, and "-", "_" characters.
configUI.displayName
String
Human-readable extension name. This name is displayed on the Dynatrace Monitoring extensions page once the extension is uploaded.

Metrics

This part of the JSON defines which metrics are collected by the extension. Each metric is defined by JSON in a format similar to the following:

{
    "timeseries": {
      "key": "Queue.ConsumerCount",
      "unit": "Count",
      "displayname": "Queue Consumer Count",
      "dimensions": [
        "rx_pid"
      ]
    },
    "alert_settings": [
      {
        "alert_id": "too_many_consumers",
        "event_type": "PERFORMANCE_EVENT",
        "event_name": "Too many consumers",
        "description": "The {metricname} of {severity} is {alert_condition} the threshold of {threshold}",
        "threshold": 35.0,
        "alert_condition": "ABOVE",
        "samples":5,
        "violating_samples":3,
        "dealerting_samples":5,
        "value_extractor": "MAX"
      }
    ],
    "source": {
      "domain": "org.hornetq",
      "keyProperties": {
        "type": "Queue"
      },
      "attribute": "ConsumerCount"
    }
  }

Timeseries

This part specifies the metadata of a metric.

Field
Type
Description
key
String
Metric name. Must be unique within this extension. Only letters, numbers, and "-" , "_" characters are allowed.
unit
String
Metric unit. Must be one of the available units described below
dimensions
String array
Must contain rx_pid at index 0. This ensures that JMX attributes get the system process ID (PID) as a dimension. Additional dimensions can be used to, for example, provide one metric per JMX ObjectName key property value (for example, QueueName, ThreadPoolName, or ConnectionPoolName). Only letters, numbers, and "-" , "_" characters are allowed.
displayname
String
Metric display name representing the metric in Dynatrace. This field is obligatory. It must be different than the metric key.

Available units: NanoSecond, MicroSecond, MilliSecond, Second, Byte, KiloByte, MegaByte, BytePerSecond, BytePerMinute, KiloBytePerSecond, KiloBytePerMinute, MegaBytePerSecond, MegaBytePerMinute, Count, PerSecond, PerMinute

Alert settings

This part specifies the configuration of one or more alerts for a given timeseries.

Field
Type
Description
alert_id
String
Unique alert ID. Only letters, numbers, and "-" , "_" characters are allowed.
event_type
String
Allowed types: PERFORMANCE_EVENT, ERROR_EVENT, AVAILABILITY_EVENT.
description
String
Description defines alert message, following code snippets could be used: {threshold} the value of the custom threshold that was violated, {severity} the violating value, {entityname} the display name of the entity where the metric violated, {violating_samples} the number of violating samples that led to that event, {dimensions} a string containing the violating dimensions of the metric, {alert_condition} a string showing if above or below threshold is alerting
event_name
String
Event name displayed on UI pages.
threshold
Float
The value of the threshold.
alert_condition
String
ABOVE or BELOW.
samples
Integer
Size of the “window” in which violating_samples are counted.
violating_samples
Integer
The number of violating samples that rise an alert.
dealerting_samples
Integer
The number of not violating samples that deactivate the alert.
value_extractor
String
Dynatrace captures a value every 10 seconds but only sends one aggregate value per minute. This specifies how to aggregate these 10 second values. Possible values: MIN, MAX, SUM, COUNT, AVG, MEDIAN, P90. Default value is AVG

Source

This part specifies how a metric is collected using JMX. The following attributes are required for all metrics:

Field
Type
Description
domain
String
Domain name of the MBean
keyProperties
Key, Value pairs
Key properties of the MBean. Values can contain wildcards (*)
attribute
String
Name of attribute that contains the metric value.

Optional attributes are:

Field
Type
Description
attributePath
String
allowAdditionalKeys
Boolean
If false, the keyProperties need to match exactly. Additional keys in the name will lead to a mismatch. If true, then additional key properties beside those specified in "keyProperties" are allowed and ignored.
calculateDelta
bool
If true, calculate the change in values of the given attribute. Value = attribute(t) - attribute(t-1). This is useful for monotonically increasing values.
calculateRate
bool
If true, calculate the rate of changes per seconds. This is used in combination with calculateDelta to convert an absolute attribute (eg. Request Count) to a rate (eg. Requests per Second). Value = attribute / query interval
aggregation
String
It is used to aggregate multiple values if more than 1 MBean matches the domain and key property filter. Possible values: SUM, AVG, MIN, MAX
splitting
Object

Splitting

Splittings can be used to define an additional dimension for a metric. This dimension must be defined in the dimension property of the timeseries and the splitting property of the source.

"splitting": {
    "name": "name",
    "type": "keyProperty",
    "keyProperty": "name"
  }

To define multiple splittings, use the following format:

"splittings":[
   {
      "name":"name",
      "type":"keyProperty",
      "keyProperty":"name"
   },
   {
      "name":"context",
      "type":"keyProperty",
      "keyProperty":"context"
   }
]

The following attributes must be present for each splitting:

Field
Type
Description
name
String
Must match the dimension name defined for the timeseries
type
String
Must always be keyProperty
keyProperty
String
Defines which key property of the ObjectName of an MBean is used for splitting.

Example of a metric with an additional splitting

The following example shows how to define a metric that provides multiple timeseries within a single metric:

{
    "timeseries": {
      "key": "XY.Size",
      "unit": "Count",
      "displayname": "Queue Consumer Count",
      "dimensions": [
        "rx_pid",
        "name"
      ]
    }
    "source": {
      "domain": "com.sample",
      "keyProperties": {
        "type": "XY",
        "name": "*"
      },
      "attribute": "Size",
      "splitting": {
        "name": "name",
        "type": "keyProperty",
        "keyProperty": "name"
      }
    }
  }

For example, MBeans com.sample:type=XY,name=A and com.sample:type=XY,name=B will result in two timeseries, the first for "A" and the second for "B".

CompositeData

To extract values of individual keys returned as CompositeData type by an attribute, you need to use the attributePath mechanism and point to the key you're interested in.

For example, let's say you want to extract the value of used from the HeapMemoryUsage attribute. HeapMemoryUsage is a CompositeData type that returns the following list of value-key pairs:

{
    committed: integer,
    init: integer,
    max: integer,
    used: integer
}

Define the metric that points to the MBean with the HeapMemoryUsage attribute and, in the source section, point the attributePath to the used key. For example:

"source": {
      "domain": "java.lang",
      "keyProperties": {
        "type": "Memory",
      },
      "attribute": "HeapMemoryUsage",
      "attributePath": "get(\"used\")"
    }

UI config

This part of the JSON defines how metrics are charted on the process page. It contains a mandatory charts section and an optional keycharts section. Each section has the same format and looks like this:

{
        "ui": {
            "keymetrics" : [
             {
                    "key" : "requestCount",
                    "aggregation" : "avg",
                    "mergeaggregation" : "sum",
                    "displayname" : "Requests"
             }
            ],
            "keycharts" : [ ],
            "charts": [ ]
        }
    }

The keymetrics section is completely optional and allows you to define up to two metrics that should be part of the Process infographic. It has the following attributes:

Field
Type
Description
key
String
The key for the time series to put into the graphic. Only letters, numbers, and "-" , "_" characters are allowed.
aggregation
String
Aggregation defines the method to aggregate the minute values when working with longer timeframes. Dynatrace captures a value every 10 seconds but only sends one aggregate value per minute. This specifies how to aggregate these 10 second values.
mergeaggregation
String
If the metric contains multiple dimensions, this defines how to aggregate the dimension values into a single dimension.
displayname
String
The name to display in the infographic

Each chart section has the same format and looks like this:

{
                "group": "Section Name",
                "title": "Chart Name",
                "series": [
                 {
                        "key": "MetricName",
                        "aggregation": "avg",
                        "displayname": "Display name for metric",
                        "seriestype": "area"
                 },
                 {
                        "key": "Other Metric Name",
                        "aggregation": "avg",
                        "displayname": "Display name for metric",
                        "color": "rgba(42, 182, 244, 0.6)",
                        "seriestype": "area"
                 }
                ]
         }

The charts section describes how to chart each metric in the details section of the process page (available by selecting Further details).

Both sections allow an array of charts to be defined. A chart has the following required attributes:

Field
Type
Description
group
String
The section name that the chart should be placed in
title
String
The name of the chart
series
Array
An array of timeseries and charting definitions. One chart can contain multiple metrics.

A series has the following attributes:

Field
Type
Description
key
String
The key for the time series to chart
displayname
String
Display name to display for the metric. Overwrites the metric displayname. Default: metric displayname.
aggregation
String
How multiple minute values should be aggregated in charts when viewing a longer time frame. Possible values: SUM, AVG, MIN, MAX
mergeaggregation
String
Key charts don't show multiple dimensions. If the metric contains multiple dimensions, this defines how to aggregate the dimension values into a single dimension.
color
String
HTML notation of a color (RGB or RGBA).
seriestype
String
Chart type. Possible values are: line, area, and bar
rightaxis
Boolean
If true, the metric will be placed on the right axis instead of the left axis. Note that Dynatrace supports dual-axis charts.
stacked
Boolean
When true, multiple metrics are stacked upon each other. This only works for area and bar charts.