@cprussin/transform-package-json - v1.3.0

This package contains a CLI and an API for transforming a package.json into a new location while patching relative paths and removing development-only fields.

Installing

Use the package manager of your choice to install:

• npm: npm install --save-dev @cprussin/transform-package-json
• pnpm: pnpm add -D @cprussin/transform-package-json
• yarn: yarn add -D @cprussin/transform-package-json

CLI Usage

The CLI takes a path to an input package.json and a path to an output package.json. It will then run the following transformations on the input, saving the result to the output path:

• Remove the devDependencies and scripts fields
• If --removeType is paassed, remove the type field (for instance, you may want to do this is you're transpiling ESM to CJS)
• Update relative path references so that the new package.json points to the same files as the old one. Fields that are updated are:
  • main
  • types
  • bin
  • exports

For example, you can use the CLI by calling:

transform-package-json --removeType ./package.json ./dist/package.json

Which will convert this package.json:

{
  name: "foo",
  type: "module",
  main: "./dist/index.js",
  types: "./dist/index.d.js",
  exports: {
    import: "./dist/esm/index.mjs",
    require: "./dist/cjs/index.js",
  },
  scripts: {
    foo: "bar",
  },
  devDependencies: {
    baz: "latest",
  },
}

into this one:

{
  name: "foo",
  main: "./index.js",
  types: "./index.d.js",
  exports: {
    import: "./esm/index.mjs",
    require: "./cjs/index.js",
  },
}

API Usage

You can use transformPackageJson with an input path, output path, and optional Options as a javascript equivalent to the CLI. Alternatively, if you have a non-standard use case for loading/writing files, you can call transformPackageJsonContents, which takes the parsed contents of a package.json and an optional Options and returns the transformed contents.

Table of contents

Type Aliases

• Options
• PackageJson

Functions

• transformPackageJson
• transformPackageJsonContents

Type Aliases

Options

Ƭ Options: Object

Options that control how the package.json contents are transformed.

Type declaration

| Name | Type | Description | | :------ | :------ | :------ | | relativePathRoot? | string | If passed, this is the new root for relative paths in main, types, bin, and exports, relative to the old root. Typically this is the directory where the output will be written relative to the directory where the input file is. You only need to specify this manually if using transformPackageJsonContents as it will be automatically derived from the paths passed in when using transformPackageJson If not specified, relative paths are left alone. | | removeType? | boolean | If true, strip the type field out when transforming. |

Defined in

index.ts:106

PackageJson

Ƭ PackageJson: Record<string, unknown> & { bin?: string | Record<string, string> ; exports?: string | string[] | Nested<string> ; main?: string ; types?: string }

A simplified type describing the schema of package.json files. Here we only define fields that this library touches.

Defined in

index.ts:96

Functions

transformPackageJson

▸ transformPackageJson(input, output, options?): Promise<void>

Load the contents of the package.json file located at input, calculate the relative path root between input and output, transform the contents using transformPackageJsonContents, and write the results to output.

Parameters

| Name | Type | Description | | :------ | :------ | :------ | | input | string | the path to the input package.json | | output | string | the path that the transformed package.json will be written to | | options? | Omit<Options, "relativePathRoot"> | optional Options which will control the transformation |

Returns

Promise<void>

an empty promise that resolves when the new file is successfully written

See

transformPackageJsonContents

Defined in

index.ts:189

transformPackageJsonContents

▸ transformPackageJsonContents(contents, options?): PackageJson

Take the contents of a package.json file and optional Options and apply the transformations, returning the results. In general you won't use this directly and you'll probably want to use transformPackageJson instead, unless you have unique requirements around loading the package.json contents from disk, writing the new contents out, or calculating the new Options.relativePathRoot.

Parameters

| Name | Type | Description | | :------ | :------ | :------ | | contents | PackageJson | the contents of the package.json that you'd like to transform | | options? | Options | optional Options which will control the transformation |

Returns

PackageJson

the transformed package.json contents

See

transformPackageJson

Defined in

index.ts:142