NPX is a Node.js command executor that was introduced in NPM version 5.2.0. Its name is an acronym for “Node Package eXecutor” and its main goal is to facilitate the execution of package commands without having to install them globally.
NPX has been a significant improvement in the Node.js and NPM environment. It allows us to run package commands without the need to install them globally (which simplifies dependency management and improves project portability).
NPX automatically resolves the package location and executes it, without having to install it. What we already know can generate conflicts between projects, or give us problems when sharing projects between teams and/or individuals.
Advantages of using NPX in an NPM course
NPX offers several advantages in the context of an NPM course. Some of them are:
Avoids global package installation: With NPX, it is not necessary to globally install packages. Your computer, cleaner and happier 😉.
Prevents dependency conflicts: By not installing packages globally, it avoids dependency conflicts between different projects.
Facilitates package version management: NPX allows you to run commands with specific package versions.
Installing NPX
NPX comes pre-installed with NPM since version 5.2.0, so it does not need to be installed separately.
You can check that it is correctly installed by running this command.
npx -vBasic usage of NPX
NPX also allows you to run specific package commands without needing to install the package itself.
To do this, we use the syntax npm <package> <command> to run a specific command from a particular package. So,
npx <command> <parameters>For example, let’s imagine we want to run the command create-react-app, which creates a new React application. The package author provides us with this tool.
Previously, we would have had to install the package globally,
npm install -g create-react-appBut with NPX, we can do the same as follows,
npx create-react-app my-appIn this case, NPX will look for the create-react-app package in the local directories. If it does not find it, it will download it temporarily, execute it, and remove it after use.
This means that no files will be permanently installed on your system, which is a very important advantage over the previous global installation method, which forced you to keep installing more and more things on your machine.
Running commands with specific versions
In addition to running package commands without installing them globally, NPX also allows us to specify the version of a package that we want to use.
To run a command with a specific version of a package, you can use the following syntax:
npx <package>@<version> <command>For example, if you want to run the command my-command from version 1.0.0 of my-package, you can do it like this:
npx my-package@1.0.0 my-commandNPX will temporarily download version 1.0.0 of my-package, execute the command my-command, and remove it after use.
This can be useful when we need to run commands with specific versions to ensure compatibility or test new features.