StatsD Advanced

Log metrics for a Service, Route (or the deprecated API entity) to a StatsD server. It can also be used to log metrics on Collectd daemon by enabling its StatsD plugin.

Terminology

• plugin: a plugin executing actions inside Kong before or after a request has been proxied to the upstream API.
• Service: the Kong entity representing an external upstream API or microservice.
• Route: the Kong entity representing a way to map downstream requests to upstream services.
• Consumer: the Kong entity representing a developer or machine using the API. When using Kong, a Consumer only communicates with Kong which proxies every call to the said upstream API.
• Credential: a unique string associated with a Consumer, also referred to as an API key.
• upstream service: this refers to your own API/service sitting behind Kong, to which client requests are forwarded.
• API: a legacy entity used to represent your upstream services. Deprecated in favor of Services since CE 0.13.0 and EE 0.32.

Configuration

Enabling the plugin on a Service

With a database

Configure this plugin on a Service by making the following request:

$ curl -X POST http://kong:8001/services/{service}/plugins \
    --data "name=statsd-advanced"  \
    --data "config.host=127.0.0.1" \
    --data "config.port=8125" \
    --data "config.allow_status_codes=200-205,400-499"

Without a database

Configure this plugin on a Service by adding this section do your declarative configuration file:

plugins:
- name: statsd-advanced
  service: {service}
  config: 
    host: 127.0.0.1
    port: 8125
    allow_status_codes: 200-205,400-499

In both cases, {service} is the id or name of the Service that this plugin configuration will target.

Enabling the plugin on a Route

With a database

Configure this plugin on a Route with:

$ curl -X POST http://kong:8001/routes/{route}/plugins \
    --data "name=statsd-advanced"  \
    --data "config.host=127.0.0.1" \
    --data "config.port=8125" \
    --data "config.allow_status_codes=200-205,400-499"

Without a database

Configure this plugin on a Route by adding this section do your declarative configuration file:

plugins:
- name: statsd-advanced
  route: {route}
  config: 
    host: 127.0.0.1
    port: 8125
    allow_status_codes: 200-205,400-499

In both cases, {route} is the id or name of the Route that this plugin configuration will target.

Enabling the plugin on a Consumer

With a database

You can use the http://localhost:8001/plugins endpoint to enable this plugin on specific Consumers:

$ curl -X POST http://kong:8001/consumers/{consumer}/plugins \
    --data "name=statsd-advanced" \
     \
    --data "config.host=127.0.0.1" \
    --data "config.port=8125" \
    --data "config.allow_status_codes=200-205,400-499"

Without a database

Configure this plugin on a Consumer by adding this section do your declarative configuration file:

plugins:
- name: statsd-advanced
  consumer: {consumer}
  config: 
    host: 127.0.0.1
    port: 8125
    allow_status_codes: 200-205,400-499

In both cases, {consumer} is the id or username of the Consumer that this plugin configuration will target.

You can combine consumer_id and service_id

in the same request, to furthermore narrow the scope of the plugin.

Enabling the plugin on an API

If you are using an older version of Kong with the legacy API entity (deprecated in favor of Services since CE 0.13.0 and EE 0.32.), you can configure this plugin on top of such an API by making the following request:

$ curl -X POST http://kong:8001/apis/{api}/plugins \
    --data "name=statsd-advanced"  \
    --data "config.host=127.0.0.1" \
    --data "config.port=8125" \
    --data "config.allow_status_codes=200-205,400-499"

• api: either id or name of the API that this plugin configuration will target.

Global plugins

• Using a database, all plugins can be configured using the http://kong:8001/plugins/ endpoint.
• Without a database, all plugins can be configured via the plugins: entry on the declarative configuration file.

A plugin which is not associated to any Service, Route or Consumer (or API, if you are using an older version of Kong) is considered "global", and will be run on every request. Read the Plugin Reference and the Plugin Precedence sections for more information.

Parameters

Here's a list of all the parameters which can be used in this plugin's configuration:

By default the Plugin sends a packet for each metric it observes. udp_packet_size configures the greatest datagram size the Plugin can combine. It should be less than 65507 according to UDP protocol. Please consider the MTU of the network when setting this parameter.

Metrics

If a request URI doesn’t match any Routes, the following metrics will be sent instead:

Metric Fields

Plugin can be configured with any combination of Metrics, with each entry containing the following fields:

Metric Behaviors

1. By default all metrics get logged.
2. Metric with stat_type set to counter or gauge must have sample_rate defined as well.
3. unique_users metric only works with stat_type as set.
4. status_count, status_count_per_user, status_count_per_user_per_route and request_per_user work only with stat_type as counter.
5. shdict_usage work only with stat_type as gauge.
6. status_count_per_user, request_per_user, unique_users and status_count_per_user_per_route must have customer_identifier defined.
7. All metrics can optionally configure service_identifier; by default it’s set to service_name_or_host.
8. status_count_per_workspace must have workspace_identifier defined.

Kong Process Errors

This logging Plugin will only log HTTP request and response data. If you are looking for the Kong process error file (which is the nginx error file), then you can find it at the following path: {prefix}/logs/error.log