Optional Require

node.js require that let you handle module not found error without try/catch. Allows you to gracefully require a module only if it exists and contains no error.

Why not try/catch?

So why not just do:

let some;
try {
  some = require("some-optional-module");
} catch {
  // do nothing
}

1. Variable scoping: You need to keep the variable outside: let some before try/catch
2. Error differentiation: You need additional logic to distinguish between "module not found" vs "module has syntax/runtime errors". If "some-optional-module" contains error itself, above code will silently ignore it, leaving you, and more importantly, your users, puzzling on why it's not working -- the original reason that prompted the creation of this package.
3. Code readability: Nested try/catch blocks make code harder to read and maintain, especially when dealing with multiple optional modules

Usage

ES Modules:

import { optionalRequire } from "optional-require";

const some = optionalRequire("some-optional-module");
const bar = optionalRequire("bar", true); // log message when not found
const xyz = optionalRequire("xyz", "test"); // log with custom message
const fbPath = optionalRequire.resolve("foo", "foo doesn't exist");

CommonJS:

const { optionalRequire } = require("optional-require");

const foo = optionalRequire("foo") || {};
const rel = optionalRequire("../foo/bar", { require }); // relative paths need require

Custom Context

To require modules relative to your file, bind the function to your context:

ESM:

import { makeOptionalRequire } from "optional-require";
const optionalRequire = makeOptionalRequire(import.meta.url);
const myModule = optionalRequire("./my-module");

CommonJS:

const { makeOptionalRequire } = require("optional-require");
const optionalRequire = makeOptionalRequire(__dirname);
// or
const optionalRequire = makeOptionalRequire(require);
const myModule = optionalRequire("./my-module");

Requirements

• Node.js 20+: Full support for both ESM and CommonJS through conditional exports

Legacy Usage

In older versions, this module exports makeOptionalRequire directly and this is the legacy usage in CommonJS only, which is still supported:

const optionalRequire = require("optional-require")(require);

const foo = optionalRequire("foo") || {};
const bar = optionalRequire("bar", true); // true enables console.log a message when not found
const xyz = optionalRequire("xyz", "test"); // "test" enables console.log a message with "test" added.
const fbPath = optionalRequire.resolve("foo", "foo doesn't exist");
const rel = optionalRequire("../foo/bar"); // relative module path works

Note: This legacy pattern only works in CommonJS mode since it relies on the require function.

API

https://jchip.github.io/optional-require/modules.html#optionalrequire

LICENSE

Apache-2.0 © Joel Chen