@nimpl/config

(Former next-impl-config )

The package adding support for configuration for each possible next.js environment (build, server, client, and edge)

Motivation 

For the config, Next.js only offers environment variables - regular ones for the server, and ones with NEXT_PUBLIC prefix, which will be embedded during the build process.

And here are a few downsides:

• It's not convenient for large configuration objects.
• It doesn't cover all use cases, such as runtime config and react runtime config (when the image is built once and used in different environments).

On the other hand, @nimpl/config offers support for 4 different configuration options for your applications.

Another important advantage of @nimpl/config is that it supports functions (synchronous and asynchronous) and will successfully merge their result.

Installation 

npm i @nimpl/config

Usage 

server

The config is generated at runtime (based on the environment conditions at runtime).

Recommended for API routes or in force-dynamic mode in server components.

import { serverConfig } from '@nimpl/config/server-config';
// ...
const config = await serverConfig;

build

The config is generated at build time (based on the environment conditions at build time).

Recommended for components that don't depend on the runtime environment.

import { buildConfig } from '@nimpl/config/build-config';
// ...
const config = buildConfig;

Before using this config, additional setup  is required

postbuild

During the build process, configs are generated for each possible environment (based on the environment conditions at build time). Then, at runtime, the appropriate version is selected.

Recommended for middleware.

import { postbuildConfig } from '@nimpl/config/postbuild-config';
// ...
const config = postbuildConfig;

Before using this config, additional setup  is required

runtime

An API route is created that generates the config at the time of the request (based on the environment conditions at runtime). Then, on the client side, a provider is initialized that loads the config and returns it after loading (triggering a re-render).

Recommended for components that depend on the runtime environment.

'client';

import useRuntimeConfig from '@nimpl/config/use-runtime-config';
// ...
const config = useRuntimeConfig();

if (!config) return <p>Loading...</p>
// ...

Before using this config, additional setup  is required

Structure 

All configs are stored in the config directory. Each variant is stored independently in a subdirectory with the same name.

config

• server
• build
• postbuild
• runtime

All types support the following config variants:

• default.js
• default.local.js
• [TARGET_ENV].js
• [TARGET_ENV].local.js
• envs.js
• envs.local.js

The lower the config variant is in the list, the higher its priority.

• default.js: Used as the default value, all config keys should be filled in this file.
• [TARGET_ENV].js: Environment-dependent config (see environment-dependent config).
• envs.js: Config with environment variables as values.
• .local.js versions: Local versions that should be added to gitignore.

Package configuration 

Environment-dependent config 

The default Environment-dependent config is the config for the current NODE_ENV or NIMPL_CONFIG_ENV. If you want to use a config for specific env, pass it to nimplConfig

const { default: nimplConfig } = require('@nimpl/config/with-nimpl-config');

/** @type {import('next').NextConfig} */
const nextConfig = {
  // ...
};

module.exports = nimplConfig({ envs: ['development', 'staging', 'production'], targetEnv: 'development' })(nextConfig);

Custom config folder 

const { default: nimplConfig } = require('@nimpl/config/with-nimpl-config');

/** @type {import('next').NextConfig} */
const nextConfig = {
  // ...
};

module.exports = nimplConfig({ folder: 'custom-config-folder' })(nextConfig);

Typescript 

When the application runs, the package will create a file with type declarations - nimpl-config.d.ts.

After this, each config variant will be typed exactly in accordance with the default config.

You can also create this file manually:

// NOTE: This file should not be edited
// see https://nimpl.tech/config/configuration#typescript for more information.

declare module "@nimpl/config/use-runtime-config" {
    declare const useRuntimeConfig: () => typeof import('./config/runtime/default');
    export default useRuntimeConfig;
}

declare module "@nimpl/config/build-config" {
    export declare const buildConfig: typeof import('./config/build/default');
}

declare module "@nimpl/config/postbuild-config" {
    export declare const postbuildConfig: typeof import('./config/postbuild/default');
}

declare module "@nimpl/config/server-config" {
    export declare const serverConfig: Promise<typeof import('./config/server/default')>;
}

App configuration 

server

This type doesn't require any additional configuration.

build

Next.js config needs to be wrapped with nimplConfig.

const { default: nimplConfig } = require('@nimpl/config/with-nimpl-config');

/** @type {import('next').NextConfig} */
const nextConfig = {
  // ...
};

module.exports = nimplConfig()(nextConfig);

postbuild

Possible environments need to be passed to nimplConfig.

const { default: nimplConfig } = require('@nimpl/config/with-nimpl-config');

/** @type {import('next').NextConfig} */
const nextConfig = {
  // ...
};

module.exports = nimplConfig({ envs: ['development', 'staging', 'production'] })(nextConfig);

runtime

First, create an API route.

export { runtimeConfigApi as GET } from '@nimpl/config/runtime-config-api';

export const dynamic = 'force-dynamic';

Wrap the application with the Provider.

import RuntimeConfigProvider from '@nimpl/config/runtime-config-provider';

export default function RootLayout() {
  return (
    <RuntimeConfigProvider apiPath='/api/config'>
      // ...
    </RuntimeConfigProvider>
  );
}

Examples 

Base example .

Development 

Read about working on the package and making changes on the contribution page 

Additional 

Please consider giving a star if you like it, it shows that the package is useful and helps continue work on this and other packages.

Create issues with wishes, ideas, difficulties, etc. All of them will definitely be considered and thought over.