1.8

How to use Kong on DC/OS

Kong is a scalable, open source API Layer (also known as an API Gateway, or API Middleware). Kong runs in front of any RESTful API and is extended through Plugins, which provide extra functionality and services beyond the core platform. DC/OS allows you to quickly configure and manage Kong.

• Estimated time for completion: 5 minutes
• Target audience: Anyone interested in running an API gateway server
• Scope: Learn how to install Kong on DC/OS

Prerequisites

• A running DC/OS 1.8 cluster with 1.3 CPUs and 1 GB of RAM available.
• Marathon-LB installed
• Postgresql installed

Install Postgresql

First install a postgresql database in your DC/OS cluster using the existing Universe package. Configure the package by creating a file called options.json with following:

{
  "service": {
    "name": "postgresql"
  },
  "postgresql": {
    "cpus": 0.3,
    "mem": 512
  },
  "database": {
    "username": "kong",
    "password": "kong",
    "dbname": "kong"
  },
  "storage": {
    "host_volume": "/tmp",
    "pgdata": "pgdata",
    "persistence": {
      "enable": true,
      "volume_size": 512,
      "external": {
        "enable": false,
        "volume_name": "postgresql",
        "provider": "dvdi",
        "driver": "rexray"
      }
    }
  },
  "networking": {
    "port": 5432,
    "host_mode": false,
    "external_access": {
      "enable": false,
      "external_access_port": 15432
    }
  }
}

The above options.json file configures Postgresql as follows:

• username: This parameter configures the username for the kong database.
• password: This parameter configures the password for the kong database.
• dbname: This parameter configures the name of the kong database.
• persistence: This parameter enables persistent volumes for postgresql.

Install postgresql using this options.json file:

$ dcos package install postgresql --options=options.json

To verify that our postgresql instance is up and running, we can use dcos task command:

$ dcos task
NAME         HOST        USER  STATE  ID
marathon-lb  10.0.6.130  root    R    marathon-lb.104e0ebe-03be-11e7-b790-627a33830456
postgresql   10.0.0.71   root    R    postgresql.0f2867a0-03cb-11e7-b790-627a33830456

Install Kong

Next, install Kong. If you have installed postgresql with a different username, password, dbname, or id, customize the kong installation accordingly.

$ dcos package install kong
This DC/OS Service is currently EXPERIMENTAL. There may be bugs, incomplete features, incorrect documentation, or other discrepancies. Prerequisites for this service include postgres and marathon-lb. See https://github.com/dcos/examples/tree/master/1.8/kong for more details.
Continue installing? [yes/no] yes
Installing Marathon app for package [kong] version [0.9.9]
Kong has been installed.

To verify that our kong instance is up and running, we can use dcos task command:

$ dcos task
NAME         HOST        USER  STATE  ID
kong         10.0.0.71   root    R    kong.c2cd2cc9-03cb-11e7-b790-627a33830456
marathon-lb  10.0.6.130  root    R    marathon-lb.104e0ebe-03be-11e7-b790-627a33830456
postgresql   10.0.0.71   root    R    postgresql.0f2867a0-03cb-11e7-b790-627a33830456

Kong in the DC/OS UI

Now that Kong is installed, curl the marathon-lb endpoint to validate that it is up and running curl http://<public-agent-ip>:10002 You should see output similar to this:

Uninstall Kong

To uninstall Kong, run following command:

dcos package uninstall kong