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# get-stream [![Build Status](https://travis-ci.com/sindresorhus/get-stream.svg?branch=master)](https://travis-ci.com/github/sindresorhus/get-stream)
> Get a stream as a string, buffer, or array
## Install
```
$ npm install get-stream
```
## Usage
```js
const fs = require('fs');
const getStream = require('get-stream');
(async () => {
const stream = fs.createReadStream('unicorn.txt');
console.log(await getStream(stream));
/*
,,))))))));,
__)))))))))))))),
\|/ -\(((((''''((((((((.
-*-==//////(('' . `)))))),
/|\ ))| o ;-. '((((( ,(,
( `| / ) ;))))' ,_))^;(~
| | | ,))((((_ _____------~~~-. %,;(;(>';'~
o_); ; )))(((` ~---~ `:: \ %%~~)(v;(`('~
; ''''```` `: `:::|\,__,%% );`'; ~
| _ ) / `:|`----' `-'
______/\/~ | / /
/~;;.____/;;' / ___--,-( `;;;/
/ // _;______;'------~~~~~ /;;/\ /
// | | / ; \;;,\
(<_ | ; /',/-----' _>
\_| ||_ //~;~~~~~~~~~
`\_| (,~~
\~\
~~
*/
})();
```
## API
The methods returns a promise that resolves when the `end` event fires on the stream, indicating that there is no more data to be read. The stream is switched to flowing mode.
### getStream(stream, options?)
Get the `stream` as a string.
#### options
Type: `object`
##### encoding
Type: `string`\
Default: `'utf8'`
[Encoding](https://nodejs.org/api/buffer.html#buffer_buffer) of the incoming stream.
##### maxBuffer
Type: `number`\
Default: `Infinity`
Maximum length of the returned string. If it exceeds this value before the stream ends, the promise will be rejected with a `getStream.MaxBufferError` error.
### getStream.buffer(stream, options?)
Get the `stream` as a buffer.
It honors the `maxBuffer` option as above, but it refers to byte length rather than string length.
### getStream.array(stream, options?)
Get the `stream` as an array of values.
It honors both the `maxBuffer` and `encoding` options. The behavior changes slightly based on the encoding chosen:
- When `encoding` is unset, it assumes an [object mode stream](https://nodesource.com/blog/understanding-object-streams/) and collects values emitted from `stream` unmodified. In this case `maxBuffer` refers to the number of items in the array (not the sum of their sizes).
- When `encoding` is set to `buffer`, it collects an array of buffers. `maxBuffer` refers to the summed byte lengths of every buffer in the array.
- When `encoding` is set to anything else, it collects an array of strings. `maxBuffer` refers to the summed character lengths of every string in the array.
## Errors
If the input stream emits an `error` event, the promise will be rejected with the error. The buffered data will be attached to the `bufferedData` property of the error.
```js
(async () => {
try {
await getStream(streamThatErrorsAtTheEnd('unicorn'));
} catch (error) {
console.log(error.bufferedData);
//=> 'unicorn'
}
})()
```
## FAQ
### How is this different from [`concat-stream`](https://github.com/maxogden/concat-stream)?
This module accepts a stream instead of being one and returns a promise instead of using a callback. The API is simpler and it only supports returning a string, buffer, or array. It doesn't have a fragile type inference. You explicitly choose what you want. And it doesn't depend on the huge `readable-stream` package.
## Related
- [get-stdin](https://github.com/sindresorhus/get-stdin) - Get stdin as a string or buffer
---
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