# package-json

> Get metadata of a package from the npm registry

## Install

```
$ npm install package-json
```

## Usage

```js
const packageJson = require('package-json');

(async () => {
	console.log(await packageJson('ava'));
	//=> {name: 'ava', ...}

	// Also works with scoped packages
	console.log(await packageJson('@sindresorhus/df'));
})();
```

## API

### packageJson(packageName, options?)

#### packageName

Type: `string`

Name of the package.

#### options

Type: `object`

##### version

Type: `string`\
Default: `latest`

Package version such as `1.0.0` or a [dist tag](https://docs.npmjs.com/cli/dist-tag) such as `latest`.

The version can also be in any format supported by the [semver](https://github.com/npm/node-semver) module. For example:

- `1` - Get the latest `1.x.x`
- `1.2` - Get the latest `1.2.x`
- `^1.2.3` - Get the latest `1.x.x` but at least `1.2.3`
- `~1.2.3` - Get the latest `1.2.x` but at least `1.2.3`

##### fullMetadata

Type: `boolean`\
Default: `false`

By default, only an abbreviated metadata object is returned for performance reasons. [Read more.](https://github.com/npm/registry/blob/master/docs/responses/package-metadata.md)

##### allVersions

Type: `boolean`\
Default: `false`

Return the [main entry](https://registry.npmjs.org/ava) containing all versions.

##### registryUrl

Type: `string`\
Default: Auto-detected

The registry URL is by default inferred from the npm defaults and `.npmrc`. This is beneficial as `package-json` and any project using it will work just like npm. This option is **only** intended for internal tools. You should **not** use this option in reusable packages. Prefer just using `.npmrc` whenever possible.

##### agent

Type: `http.Agent | https.Agent | object | false`

Overwrite the `agent` option that is passed down to [`got`](https://github.com/sindresorhus/got#agent). This might be useful to add [proxy support](https://github.com/sindresorhus/got#proxies).

### packageJson.PackageNotFoundError

The error thrown when the given package name cannot be found.

### packageJson.VersionNotFoundError

The error thrown when the given package version cannot be found.

## Authentication

Both public and private registries are supported, for both scoped and unscoped packages, as long as the registry uses either bearer tokens or basic authentication.

## package-json for enterprise

Available as part of the Tidelift Subscription.

The maintainers of package-json and thousands of other packages are working with Tidelift to deliver commercial support and maintenance for the open source dependencies you use to build your applications. Save time, reduce risk, and improve code health, while paying the maintainers of the exact dependencies you use. [Learn more.](https://tidelift.com/subscription/pkg/npm-package-json?utm_source=npm-package-json&utm_medium=referral&utm_campaign=enterprise&utm_term=repo)

## Related

- [package-json-cli](https://github.com/sindresorhus/package-json-cli) - CLI for this module
- [latest-version](https://github.com/sindresorhus/latest-version) - Get the latest version of an npm package
- [pkg-versions](https://github.com/sindresorhus/pkg-versions) - Get the version numbers of a package from the npm registry
- [npm-keyword](https://github.com/sindresorhus/npm-keyword) - Get a list of npm packages with a certain keyword
- [npm-user](https://github.com/sindresorhus/npm-user) - Get user info of an npm user
- [npm-email](https://github.com/sindresorhus/npm-email) - Get the email of an npm user
