@nlv8/reconvict

Drop-in replacement for node-convict with runtime configuration reloading.

Usage no npm install needed!

<script type="module">
  import nlv8Reconvict from 'https://cdn.skypack.dev/@nlv8/reconvict';
</script>

README

reconvict

Drop-in replacement for node-convict with support for runtime configuration reloading like an absolute boss.

Features

  • Live configuration objects: Getting nested objects from the configuration will return live objects that reflect configuration changes.
  • Emission of configuration changes: A configuration is an EventEmitter that will emit modified keys upon changes.
  • Reloaders: Built-in support for detecting changes in configuration sources and actualizing the runtime configuration.
  • And everything supported by node-convict:
    • Loading and merging,
    • Nested structure,
    • Environmental variables,
    • Command-line arguments,
    • Validation,
    • Comments allowed,
    • Configuration file additional types support.

Install

npm install @nlv8/reconvict

Usage

An example config.js file:

var reconvict = require('@nlv8/reconvict');

// Define a schema
var config = reconvict({
  env: {
    doc: "The application environment.",
    format: ["production", "development", "test"],
    default: "development",
    env: "NODE_ENV"
  },
  greeting: {
    message: {
      doc: 'The greeting message presented to users.',
      format: String,
      default: 'Hello!'
    }
  },
  server: {
    ip: {
      doc: "The IP address to bind.",
      format: "ipaddress",
      default: "127.0.0.1",
      env: "IP_ADDRESS",
    },
    port: {
      doc: "The port to bind.",
      format: "port",
      default: 8080,
      env: "PORT",
      arg: "port"
    }
  }
});

// Load environment dependent configuration
var env = config.get('env');
config.loadFile('./config/' + env + '.json');

// Perform validation
config.validate({allowed: 'strict'});

module.exports = config;

An example server.js file leveraging the config.js file above:

var http = require('http');
var config = require('./config.js');

// Listening on changes like an absolute boss.
config.on('change', (changedKeys, config) => {
  console.log('Configuration changed! Changed keys and values:');

  changedKeys.forEach(key => {
    console.log(`${key} – ${config.get(key)}`)
  })
});

const greeting = config.get('greeting')

var server = http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  // Will magically change to the latest configuration value :)
  // However, you cannot modify it :O
  res.end(`${greeting.message}\n`);
});

server.listen(config.get('port'), config.get('ip'), function(x) {
  var addy = server.address();
  console.log('running on http://' + addy.address + ":" + addy.port);
});

// Let's make some change.
setTimeout(() => {
  config.set('greeting.message', 'Hola!');
}, 10000)

To launch your example server, and set a port:

node ./server.js --port 8080

Note: arguments must be supplied with the double-hyphen --arg. (Single hypen's are not supported at this time)

API

For the original node-convict methods, please see: node-convict/API.

config.forceLoad(object)

Works the same as load but will ignore environment variables and arguments originally given to the script.

config.forceLoadFile(file or fileArray)

Works the same as load but will ignore environment variables and arguments originally given to the script.