Figue - Application configuration management

The modern way to handle and validate your application configuration with any standard-schema-compliant validation library.

Introduction

Figue is a modern configuration management library for Node.js. It is designed to be easy to use, flexible, it can used in any environment, and can be used with any standard-schema-compliant validation library, like zod or valibot.

Think of it as a modern version of convict but simpler, cross env and using battle tested validation libraries.

Features

• Environment variables support
• Validation with any standard-schema-compliant validation library
• Flat object support
• Multiple sources of configuration
• Type-safe configuration
• Composable configuration

Usage

Install package:

# pnpm
pnpm install figue

# npm
npm install figue

# yarn
yarn install figue

Import:

// ESM
import { defineConfig } from 'figue';

// CommonJS
const { defineConfig } = require('figue');

API

Basic example

Use the defineConfig function to define your configuration, here with valibot:

import { defineConfig } from 'figue';
import * as v from 'valibot';

const { config } = defineConfig(
  {
    env: {
      doc: 'Application current environment',
      default: 'development',
      schema: v.picklist(['development', 'production', 'test']),
      env: 'NODE_ENV',
    },
    port: {
      doc: 'Application port to listen',
      schema: v.pipe(v.union([v.number(), v.string()]), v.transform(Number)),
      default: 3000,
      env: 'PORT',
    },
    db: {
      host: {
        doc: 'Database server url',
        schema: v.pipe(v.string(), v.url()),
        default: 'http://localhost:5432',
        env: 'APP_DB_HOST',
      },
      username: {
        doc: 'Database server username',
        schema: v.string(),
        default: 'pg',
        env: 'APP_DB_USERNAME',
      },
      password: {
        doc: 'Database server password',
        schema: v.string(),
        default: '',
        env: 'APP_DB_PASSWORD',
      },
    },
  },
  {
    envSource: process.env,
  },
);

console.log(config);
// {
//   env: "development",
//   port: 3000,
//   db: {
//     url: "https://localhost",
//     username: "pg",
//     password: "",
//   },
// }

You can see more examples in the demo folder.

• Figue with zod: demo/figue-zod.ts
• Figue with valibot: demo/figue-valibot.ts

Load environnement

Use the envSource key of the second argument of defineConfig to specify the source of the environment variables:

const { config } = defineConfig(
  {
    /* ... */
  },
  {
    envSource: process.env,
  },
);

In some case you don't have access to a process.env variable, like with vite, just simply load what stores your env variables :

const { config } = defineConfig(
  {
    /* ... */
  },
  {
    envSource: import.meta.env,
  },
);

You can even specify you custom environment storage as long as it's a simple flat object map, for example:

const { config } = defineConfig(
  {
    env: {
      doc: 'Application current environment',
      default: 'development',
      schema: z.enum(['development', 'production', 'test']),
      env: 'NODE_ENV',
    },

    /* ... */
  },
  {
    envSource: {
      NODE_ENV: 'development',
      PORT: '3000',
      APP_DB_HOST: 'localhost',
      APP_DB_USERNAME: 'pg',
      APP_DB_PASSWORD: '',
    },
  },
);

If, for some reason, you have multiple sources of environment variables, you can use the envSources key of the second argument of defineConfig to specify an array of sources:

const { config } = defineConfig(
  {
    /* ... */
  },
  {
    envSource: [import.meta.env, myEnvs],
  },
);

Get defaults

You can use the getDefaults key of the second argument of defineConfig to specify a function that will be called to get some defaults:

const { config } = defineConfig(
  {
    env: {
      doc: 'Application current environment',
      default: 'development',
      schema: z.enum(['development', 'production', 'test']),
      env: 'NODE_ENV',
    },
    port: {
      doc: 'Application port to listen',
      schema: z.coerce.number().int().positive(),
      default: 3000,
      env: 'PORT',
    },
  },
  {
    envSource: {
      PORT: 3001,
    },
    // The config argument is build from the config definition defaults and the envSources
    // Typically you will use it to override some defaults based the config
    getDefaults: ({ config }) => ({
      port: config.env === 'test' ? 4444 : config.port,
    }),
  },
);

You can also use the defaults property of the second argument of defineConfig to specify some static defaults (for example taken from a json file):

const { config } = defineConfig(
  {
    /* ... */
  },
  {
    // Either an array of config partial...
    defaults: [
      {
        port: 4444,
      },
    ],

    // ... or a single config partial
    defaults: {
      port: 4444,
    },
  },
);

What's wrong with convict?

Convict is meant to be used in node based environnement, it needs to have access to global variables that may may not be present in some environnement (like process, global), and it also imports fs.

Figue?

Figue is the french for fig -> con-fig.

Development

• Clone this repository
• Install dependencies using pnpm install
• Run interactive tests using pnpm dev

Credits

This project is crafted with ❤️ by Corentin Thomasset. If you find this project helpful, please consider supporting my work.

Fig icons created by Freepik - Flaticon

License

This project is under the MIT license.