another-one-bites-the-dust

Any services status monitor. It will help answer the question "Is everything okay?"

Features

• Easy configuration
• It's standalone service. You can use it to check resources on a private network
• You can write your own checkers and check whatever you want
• Groups of checks (for different types of checks or different environments for example)
• JavaScript (I'm so sorry)

It's not for

• Alerts and notifications
• Retrospective

Built-in checkers

• Simple HTTP status checker
• Dockerflow __heartbeat__ checker

How to use

You will need Node.js v12+.

Simple way

Fork boilerplate app or just clone it.

git clone git@github.com:gwer/another-one-bites-the-dust-app.git
cd another-one-bites-the-dust-app
yarn
yarn start

Don't forget to write your own config.

Note: cloned repository is another-one-bites-the-dust-app. It is not recommended to clone the current repository for direct use.

From scratch

yarn add another-one-bites-the-dust

// index.js

const server = require('another-one-bites-the-dust');
const config = require('./config');

server(config);

node index.js

Config example

example_config.js

Built-in checkers options

Only url is required.

{
  url,
  expectedHttpCode = 200,
  timeout = 30000,
  warningTimeout = 5000
}

How to write your own checkers

Checker is async function that returns the result in the following format:

Promise<{
  "status": "ok"|"warning"|"error",
  "details"?: string,
}>

Simple checker

const myChecker = () => ({ status: 'ok' });

Checker arguments

Let's imagine you need a strange checker that checks the performance of adding numbers.

const myChecker = (expectedExecutionTime, count) => () => {
  const startTime = performance.now();
  let sum = 0;

  for (let i = 0; i < count; i++) {
    sum += i;
  }

  const endTime = performance.now();

  if ((endTime - startTime) > expectedExecutionTime) {
    return { status: 'warning', details: 'So slow...' };
  }

  return { status: 'ok' };
};

const config = {
  ...
  {
    name: 'Strange check',
    checker: myChecker({ expectedExecutionTime: 100, count: 10000 }),
  },
  ...
}

Alternatives

If you need something simpler, try tinystatus.

If you need something more complicated, with alerts and checks history, try Gatus.