is_ready v1.1.0

Is Ready

A simple script to check if an endpoint is up yet

Usage

You can use this in a couple of ways:

• Command line application
• NodeJS modules
• A Docker container

The basic usage is the same in all three ways, with the following parameters:

• endpoints: This is a CSV of the endpoints that we're testing are up. This is a required field.
• exponential: The timeout grows exponentially (eg, 1, 2, 4, 8, 16). Default is false.
• timeout: How long to wait between tries, in milliseconds. Default is 1000.
• tries: Number of times to try before failing. Default is 30.

Be careful with exponential growth. An exponential 1 second timeout, run 30 times will end up running for nearly 70 years (2147483647000 milliseconds to be precise).

Command Line Application

You will need NodeJS installed to use the command line application

The command is is_ready check <endpoints>.

is_ready.js check <endpoint>

Options:
  --endpoints        The endpoints to check. Can be a comma-separated value.
  --exponential, -e  Makes the timeout grows exponentially (eg, 1, 2, 4, 8, 16)
                                                      [boolean] [default: false]
  --timeout          How long to wait between tries, in milliseconds
                                                        [number] [default: 1000]
  --tries            Number of times to try before failing[number] [default: 30]
  -h, --help         Show help                                         [boolean]
  -v, --version      Show version number                               [boolean]

NodeJS

You can use this inside a NodeJS application. Make sure you listen for the end event, which will receive the up status. You can also listen for a log event that tells you what it's doing.

const Ready = require('is_ready');

const endpoint = 'url-to-check.com:8080';
const opts = {
  exponential: false,
  timeout: 1000,
  tries: 30
};

const obj = Ready.isReady(endpoint, opts);

obj.on('end', status => {
  if (!status) {
    process.exit(1);
  }
});

Docker

This exposes the command line application