Extended Metrics API

Document updated on May 2, 2021

The metrics API offers a new /__stats/ endpoint in a different port and contains a lot of metrics that you can scrap in a custom collector, or you can push them to InfluxDB.

This component is unrelated to the OpenTelemetry metrics, and they can coexist. Previous to the creation of OpenTelemetry, the combination of Influx and the metrics API, offered the older versions of Grafana dashboard.

Configuration

In order to add the metrics API to your KrakenD installation add the telemetry/metrics namespace under extra_config in the root of your configuration file, e.g.:

{
  "version": 3,
  "extra_config": {
    "telemetry/metrics": {
      "collection_time": "60s",
      "proxy_disabled": false,
      "router_disabled": false,
      "backend_disabled": false,
      "endpoint_disabled": false,
      "listen_address": ":8090"
    }
  }
}

The structure of the metrics looks like this (truncated):

$curl http://localhost:8090/__stats
{
  "cmdline": [
    "/usr/bin/krakend",
    "run",
    "-c",
    "/etc/krakend/krakend.json",
    "-d"
  ],
  "krakend.router.connected": 0,
  "krakend.router.connected-gauge": 0,
  "krakend.router.connected-total": 0,
  "krakend.router.disconnected": 0,
  "krakend.router.disconnected-gauge": 0,
  "krakend.router.disconnected-total": 0,
  "krakend.service.debug.GCStats.LastGC": 1605724147216402400,
  "krakend.service.debug.GCStats.NumGC": 102,
  "krakend.service.debug.GCStats.Pause.50-percentile": 0,
  "krakend.service.debug.GCStats.Pause.75-percentile": 0,
  "krakend.service.debug.GCStats.Pause.95-percentile": 0,
  "krakend.service.debug.GCStats.Pause.99-percentile": 0,
  "krakend.service.debug.GCStats.Pause.999-percentile": 0,
  "krakend.service.debug.GCStats.Pause.count": 0,
  "krakend.service.debug.GCStats.Pause.max": 0,
  "krakend.service.debug.GCStats.Pause.mean": 0,
  "krakend.service.debug.GCStats.Pause.min": 0,
  "krakend.service.debug.GCStats.Pause.std-dev": 0,
    ...
  }
}

Push metrics to InfluxDB

You can accomplish it with the following snippet.

{
    "version": 3,
    "extra_config": {
      "telemetry/influx":{
          "address":"http://influxdb:8086",
          "ttl":"25s",
          "buffer_size":0,
          "db": "krakend",
          "username": "your-influxdb-user",
          "password": "your-influxdb-password"
      },
      "telemetry/metrics": {
        "collection_time": "30s",
        "listen_address": "127.0.0.1:8090"
      }
    }
}

The properties of the telemetry/influx are as follows:

See below how to configure InfluxDB, and you are ready to publish a Grafana dashboard.

Setting up Influx

For InfluxDB v2.x, we have included in our Telemetry Dashboards the files that create the authorization part.

For InfluxDB v1.x (older) the process is straightforward and requires you nothing else than start an Influx instance with the desired configuration.

Influx v2

If you use Docker, you can start InfluxDB as part of a docker-compose file. You need to specify in the configuration above the same data you used to run InfluxDB. For instance, the following docker-compose.yml sets the credentials you need to reflect in the KrakenD configuration.

version: "3"
services:
  influxdb:
    image: influxdb:2.4
    environment:
      - "DOCKER_INFLUXDB_INIT_MODE=setup"
      - "DOCKER_INFLUXDB_INIT_USERNAME=krakend-dev"
      - "DOCKER_INFLUXDB_INIT_PASSWORD=pas5w0rd"
      - "DOCKER_INFLUXDB_INIT_ORG=my-org"
      - "DOCKER_INFLUXDB_INIT_BUCKET=krakend"
      - "DOCKER_INFLUXDB_INIT_RETENTION=1w"
      - "DOCKER_INFLUXDB_INIT_ADMIN_TOKEN=my-super-secret-auth-token"
    ports:
      - "8086:8086"
    volumes:
      - "./config/telemetry/influx:/docker-entrypoint-initdb.d"
  krakend:
    image: krakend/krakend-ee:2.5
    volumes:
      - ./krakend:/etc/krakend
    ports:
      - "8080:8080"

In the fields db, username, and password of the component configuration reflect the same values as in DOCKER_INFLUXDB_INIT_BUCKET, DOCKER_INFLUXDB_INIT_USERNAME, and DOCKER_INFLUXDB_INIT_PASSWORD accordingly.

The Influx volume below must have the contents of the influx initdb script, that it will create the authorization needed to let KrakenD push the metrics.

Manual configuration

If you don’t want to use the automated docker-compose above, the manual steps to create the auth are:

Connect to your influx

$docker exec -it influxdb /bin/bash

Create a configuration:

$influx config create --config-name krakend-config \
  --host-url http://localhost:8086 \
  --org my-org \
  --token my-super-secret-auth-token \
  --active

Make sure to replace the values below as follows:

• config-name is a random name to identify your configuration
• org Your organization name as written during the setup of InfluxDB
• token The one you started influx with
• host-url The address where the influxdb is running (inside Docker is as shown)

Access with a web browser to http://localhost:8086 and select BUCKETS from the UI. You’ll see that there is an ID next to the bucket you created during the Setup. Copy the bucket ID.

And now launch the last command in the shell:

$influx v1 auth create \
  --read-bucket b492e6f8f3b13aaa \
  --write-bucket b492e6f8f3b13aaa \
  --username krakend-dev

Replace the ID of the buckets above with the ID you just copied, and the username as in the docker compose. The shell will ask for your password.

Now your configuration should work and start sending data to InfluxDB:

{
    "version": 3,
    "extra_config": {
        "telemetry/metrics": {
            "collection_time": "60s",
            "listen_address": ":8090"
        },
        "telemetry/influx": {
            "address": "http://localhost:8086",
            "ttl": "25s",
            "buffer_size": 100,
            "db": "krakend_db",
            "username": "user",
            "password": "password"
        }
    }
}

Make sure to type in db the bucket name you created on InfluxDB and the username and password as well.

Influx v1

When using InfluxDB v1.x, you need to specify in the configuration above the same data you used to run InfluxDB. For instance, the following docker-compose sets the credentials you need to reflect in the KrakenD configuration.

version: "3"
services:
  influxdb:
    image: influxdb:1.8
    environment:
      - "INFLUXDB_DB=krakend"
      - "INFLUXDB_USER=krakend-dev"
      - "INFLUXDB_USER_PASSWORD=pas5w0rd"
      - "INFLUXDB_ADMIN_USER=admin"
      - "INFLUXDB_ADMIN_PASSWORD=supersecretpassword"
    ports:
      - "8086:8086"
  krakend:
    image: krakend/krakend-ee:2.5
    volumes:
      - ./krakend:/etc/krakend
    ports:
      - "8080:8080"

In the fields db, username, and password of the component configuration reflect the same values as in INFLUXDB_DB, INFLUXDB_USER, and INFLUXDB_USER_PASSWORD accordingly.