How to use executables from a package installed locally in node_modules?

In a Node.js project, when installing dependencies via npm (e.g., npm install <package>), if the package contains executable files, they are typically placed in the node_modules/.bin directory of the project. Several methods exist for utilizing these executables, which I will explain step by step.

1. Using npm Scripts

Within the package.json file, we can define custom scripts that directly access executable files in the node_modules/.bin directory without needing to specify the full path. npm temporarily adds the node_modules/.bin directory to the system's PATH variable when executing scripts, enabling direct invocation of these executables.

For example, if we have installed the eslint package, we can configure it in package.json as follows:

json
{
  "scripts": {
    "lint": "eslint ."
  }
}

Then, run npm run lint to execute the eslint check.

2. Directly Invoking in the Command Line

To directly use these executables in the command line, we can call them by specifying the full path, such as:

bash
./node_modules/.bin/eslint .

This method is straightforward but somewhat cumbersome, as it requires entering the full path each time.

3. Using npx (Recommended Method)

npx is an npm package runner that enables us to execute commands from the node_modules/.bin directory with ease. npx automatically searches for executable files in the node_modules/.bin directory and runs them.

For example, to run eslint, simply use:

bash
npx eslint .

The advantage of this method is that even if eslint is not globally installed, as long as it is present locally in the project, npx can locate and execute it.

Summary

The recommended approaches for utilizing executable files in the node_modules/.bin directory are through npx or by defining scripts in package.json. Both methods eliminate the need to remember complex paths and enhance the portability and usability of the project.