80 lines
2.5 KiB
Markdown
80 lines
2.5 KiB
Markdown
|
# package-hash
|
||
|
|
|
||
|
|
Generates a hash for an installed npm package, useful for salting caches.
|
||
|
|
[AVA](https://github.com/sindresorhus/ava) for example caches precompiled test
|
||
|
|
files. It generates a salt for its cache based on the various packages that are
|
||
|
|
used when compiling the test files.
|
||
|
|
|
||
|
|
`package-hash` can generate an appropriate hash based on the package location
|
||
|
|
(on disk) and the `package.json` file. This hash is salted with a hash
|
||
|
|
for the `package-hash` itself.
|
||
|
|
|
||
|
|
`package-hash` can detect when the package-to-be-hashed is a Git repository. In
|
||
|
|
the AVA example this is useful when you're debugging one of the packages used to
|
||
|
|
compile the test files. You can clone it locally and use `npm link` so AVA can
|
||
|
|
find the clone. The hash will include the HEAD (`.git/HEAD`) and its
|
||
|
|
corresponding ref (e.g. `.git/refs/heads/master`), any packed refs
|
||
|
|
(`.git/packed-refs`), as well as the diff (`git diff`) for any non-committed
|
||
|
|
changes. This makes it really easy to test your changes without having to
|
||
|
|
explicitly clear the cache in the parent project.
|
||
|
|
|
||
|
|
## Installation
|
||
|
|
|
||
|
|
```console
|
||
|
|
$ npm install --save package-hash
|
||
|
|
```
|
||
|
|
|
||
|
|
## Usage
|
||
|
|
|
||
|
|
```js
|
||
|
|
const packageHash = require('package-hash')
|
||
|
|
|
||
|
|
// Asynchronously:
|
||
|
|
const hash = await packageHash(require.resolve('babel-core/package.json'))
|
||
|
|
|
||
|
|
// Synchronously:
|
||
|
|
const hash = packageHash.sync(require.resolve('babel-core/package.json'))
|
||
|
|
```
|
||
|
|
|
||
|
|
`packageHash()` / `packageHash.sync()` must be called with a file path for an
|
||
|
|
existing `package.json` file. To get the path to an npm package it's easiest to
|
||
|
|
use `require.resolve('the-name/package.json')`.
|
||
|
|
|
||
|
|
You can provide multiple paths:
|
||
|
|
|
||
|
|
```js
|
||
|
|
const hash = await packageHash([
|
||
|
|
require.resolve('babel-core/package.json'),
|
||
|
|
require.resolve('babel-preset-es2015/package.json')
|
||
|
|
])
|
||
|
|
```
|
||
|
|
|
||
|
|
An optional salt value can also be provided:
|
||
|
|
|
||
|
|
```js
|
||
|
|
const hash = await packageHash(require.resolve('babel-core/package.json'), 'salt value')
|
||
|
|
```
|
||
|
|
|
||
|
|
## API
|
||
|
|
|
||
|
|
### `packageHash(paths, salt?)`
|
||
|
|
|
||
|
|
`paths: string | string[]` ➜ can be a single file path, or an array of paths.
|
||
|
|
|
||
|
|
`salt: Array | Buffer | Object | string` ➜ optional. If an `Array` or `Object` (not `null`) it is first converted to a JSON string.
|
||
|
|
|
||
|
|
Returns a promise for the hex-encoded hash string.
|
||
|
|
|
||
|
|
### `packageHash.sync(paths, salt?)`
|
||
|
|
|
||
|
|
`paths: string | string[]` ➜ can be a single file path, or an array of paths.
|
||
|
|
|
||
|
|
`salt: Array | Buffer | Object | string` ➜ optional. If an `Array` or `Object` (not `null`) it is first converted to a JSON string.
|
||
|
|
|
||
|
|
Returns a hex-encoded hash string.
|
||
|
|
|
||
|
|
## Compatibility
|
||
|
|
|
||
|
|
`package-hash` has been tested with Node.js 8 and above, including Windows
|
||
|
|
support.
|