koa-healthcheck

A simple koa middleware to monitor the API.

Install

npm i --save koa-healthcheck

Configuration

Check structure

Every check object must looks like:

const check = {
  name: 'The optional check name',
  type: 'The check type',
  configuration: {},
};

Attributes:

• name: optional, he's used in the response of the '/healtcheck' to identify the state of each check. Default value is no-name- with ine index of this check.
• type: required, if the type isn't defined, the check will be skipped.
• configuration: required, contain a specific configuration for your check.

DB check

A DB check object must looks like:

const mySequelizeConf = {
  database: 'my-db',
  username: null,
  password: null,
  options: {
    storage: './tests.sqlite',
    dialect: 'sqlite'
  },
};

const myDBCheck = {
  type: 'db',
  configuration: mySequelizeConf
};

Ping check

A ping check object must looks like:

const myPingCheck = {
  type: 'ping',
  configuration: {
    url: 'http://my-awesome-site.io/another-url',
  },
};

How to use it

In the index of your project:

const Koa = require('koa');
// Import the middleware:
const healthcheckPlugin = require('koa-healthcheck');

const app = new Koa();
const myChecks = [myDBCheck, myPingCheck]; 
const versionOfMyApp = '1.2.3';

// Just setup the middleware:
healthcheckPlugin(app, myChecks, versionOfMyApp);

app.listen(3456); // enjoy !

Features

Ping

Check if the API is up and return "pong"

GET http://my-api.com/ping
HTTP/1.1 200 OK
"pong"

Healthcheck

Check the state of whole dependencies of your app.

Return and object of states.

GET http://my-api.com/healthcheck
HTTP/1.1 200 OK
{
    "my-first-check": 0,
    "my-second-check": 0,
    "my-third-check": 0
}

The key is the name of the test. The value possible are :

• 0 when the check is OK
• 1 when the check is KO

Version

Return the current version of your application based on the setup.

GET http://my-api.com/version
HTTP/1.1 200 OK
"X.Y.Z"

Metrics

Return the amont of request returned with 2XX, 4XX and 5XX status.

GET http://my-api.com/metrics
HTTP/1.1 200 OK
{
    "Http2XX": 2,
    "Http4XX": 1,
    "Http5XX": 1
}

Test it

npm run test

Dependencies

To be able to monitor databases (Mysql, Postrges, sqlite) we're using Sequelize.