You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
80 lines
1.9 KiB
80 lines
1.9 KiB
2 years ago
|
# CRC32 Stream
|
||
|
|
|
||
|
|
crc32-stream is a streaming CRC32 checksumer. It uses the [crc](https://www.npmjs.org/package/crc) module behind the scenes to reliably handle binary data and fancy character sets. Data is passed through untouched.
|
||
|
|
|
||
|
|
### Install
|
||
|
|
|
||
|
|
```bash
|
||
|
|
npm install crc32-stream --save
|
||
|
|
```
|
||
|
|
|
||
|
|
You can also use `npm install https://github.com/archiverjs/node-crc32-stream/archive/master.tar.gz` to test upcoming versions.
|
||
|
|
|
||
|
|
### Usage
|
||
|
|
|
||
|
|
#### CRC32Stream
|
||
|
|
|
||
|
|
Inherits [Transform Stream](http://nodejs.org/api/stream.html#stream_class_stream_transform) options and methods.
|
||
|
|
|
||
|
|
```js
|
||
|
|
const {CRC32Stream} = require('crc32-stream');
|
||
|
|
|
||
|
|
const source = fs.createReadStream('file.txt');
|
||
|
|
const checksum = new CRC32Stream();
|
||
|
|
|
||
|
|
checksum.on('end', function(err) {
|
||
|
|
// do something with checksum.digest() here
|
||
|
|
});
|
||
|
|
|
||
|
|
// either pipe it
|
||
|
|
source.pipe(checksum);
|
||
|
|
|
||
|
|
// or write it
|
||
|
|
checksum.write('string');
|
||
|
|
checksum.end();
|
||
|
|
```
|
||
|
|
|
||
|
|
#### DeflateCRC32Stream
|
||
|
|
|
||
|
|
Inherits [zlib.DeflateRaw](http://nodejs.org/api/zlib.html#zlib_class_zlib_deflateraw) options and methods.
|
||
|
|
|
||
|
|
```js
|
||
|
|
const {DeflateCRC32Stream} = require('crc32-stream');
|
||
|
|
|
||
|
|
const source = fs.createReadStream('file.txt');
|
||
|
|
const checksum = new DeflateCRC32Stream();
|
||
|
|
|
||
|
|
checksum.on('end', function(err) {
|
||
|
|
// do something with checksum.digest() here
|
||
|
|
});
|
||
|
|
|
||
|
|
// either pipe it
|
||
|
|
source.pipe(checksum);
|
||
|
|
|
||
|
|
// or write it
|
||
|
|
checksum.write('string');
|
||
|
|
checksum.end();
|
||
|
|
```
|
||
|
|
|
||
|
|
### Instance API
|
||
|
|
|
||
|
|
#### digest()
|
||
|
|
|
||
|
|
Returns the checksum digest in unsigned form.
|
||
|
|
|
||
|
|
#### hex()
|
||
|
|
|
||
|
|
Returns the hexadecimal representation of the checksum digest. (ie E81722F0)
|
||
|
|
|
||
|
|
#### size(compressed)
|
||
|
|
|
||
|
|
Returns the raw size/length of passed-through data.
|
||
|
|
|
||
|
|
If `compressed` is `true`, it returns compressed length instead. (DeflateCRC32Stream)
|
||
|
|
|
||
|
|
## Things of Interest
|
||
|
|
|
||
|
|
- [Changelog](https://github.com/archiverjs/node-crc32-stream/releases)
|
||
|
|
- [Contributing](https://github.com/archiverjs/node-crc32-stream/blob/master/CONTRIBUTING.md)
|
||
|
|
- [MIT License](https://github.com/archiverjs/node-crc32-stream/blob/master/LICENSE-MIT)
|