package-manager-detector

Package manager detector is based on lock files, the package.json packageManager field, and installation metadata to detect the package manager used in a project.

It supports npm, yarn, pnpm, deno, and bun.

Install

1# pnpm
2pnpm add package-manager-detector
3
4# npm
5npm i package-manager-detector
6
7# yarn
8yarn add package-manager-detector

Usage

To check the file system for which package manager is used:

1import { detect } from 'package-manager-detector/detect'

or to get the currently running package manager:

1import { getUserAgent } from 'package-manager-detector/detect'

Customize Detection Strategy

By default, the detect API searches through the current directory for lock files, and if none exists, it looks for the packageManager field in package.json. If that also doesn't exist, it will check the devEngines.packageManager field in package.json. If all strategies couldn't detect the package manager, it'll crawl upwards to the parent directory and repeat the detection process until it reaches the root directory.

The strategies can be configured through detect's strategies option with the following accepted strategies:

• 'lockfile': Look up for lock files.
• 'packageManager-field': Look up for the packageManager field in package.json.
• 'devEngines-field': Look up for the devEngines.packageManager field in package.json.
• 'install-metadata': Look up for installation metadata added by package managers.

The order of the strategies can also be changed to prioritize one strategy over another. For example, if you prefer to detect the package manager used for installation:

1import { detect } from 'package-manager-detector/detect'
2
3const pm = await detect({
4  strategies: ['install-metadata', 'lockfile', 'packageManager-field', 'devEngines-field']
5})

Agents and Commands

This package includes package manager agents and their corresponding commands for:

• 'agent' - run the package manager with no arguments
• 'install' - install dependencies
• 'frozen' - install dependencies using frozen lockfile
• 'add' - add dependencies
• 'uninstall' - remove dependencies
• 'global' - install global packages
• 'global_uninstall' - remove global packages
• 'upgrade' - upgrade dependencies
• 'upgrade-interactive' - upgrade dependencies interactively: not available for npm and bun
• 'execute' - download & execute binary scripts
• 'execute-local' - execute binary scripts (from package locally installed)
• 'run' - run package.json scripts

Using Agents and Commands

A resolveCommand function is provided to resolve the command for a specific agent.

1import { resolveCommand } from 'package-manager-detector/commands'
2import { detect } from 'package-manager-detector/detect'
3
4const pm = await detect()
5if (!pm)
6  throw new Error('Could not detect package manager')
7
8const { command, args } = resolveCommand(pm.agent, 'add', ['@antfu/ni']) // { command: 'pnpm', args: ['add', '@antfu/ni'] }
9console.log(`Detected the ${pm.agent} package manager. You can run a install with ${command} ${args.join(' ')}`)

You can check the source code or the JSDocs for more information.

License

MIT License © 2020-PRESENT Anthony Fu