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# etag
[![NPM Version][npm-image]][npm-url]
[![NPM Downloads][downloads-image]][downloads-url]
[![Node.js Version][node-version-image]][node-version-url]
[![Build Status][travis-image]][travis-url]
[![Test Coverage][coveralls-image]][coveralls-url]
Create simple ETags
## Installation
```sh
$ npm install etag
```
## API
```js
var etag = require('etag')
```
### etag(entity, [options])
Generate a strong ETag for the given entity. This should be the complete
body of the entity. Strings, `Buffer`s, and `fs.Stats` are accepted. By
default, a strong ETag is generated except for `fs.Stats`, which will
generate a weak ETag (this can be overwritten by `options.weak`).
```js
res.setHeader('ETag', etag(body))
```
#### Options
`etag` accepts these properties in the options object.
##### weak
Specifies if a "strong" or a "weak" ETag will be generated. The ETag can only
really be a strong as the given input.
## Testing
```sh
$ npm test
```
## Benchmark
```bash
$ npm run-script bench
> etag@1.5.1 bench nodejs-etag
> node benchmark/index.js
> node benchmark/body0-100b.js
100B body
1 test completed.
2 tests completed.
3 tests completed.
4 tests completed.
buffer - strong x 425,007 ops/sec ±1.47% (184 runs sampled)
* buffer - weak x 1,009,859 ops/sec ±0.18% (197 runs sampled)
string - strong x 442,096 ops/sec ±1.20% (181 runs sampled)
string - weak x 325,063 ops/sec ±0.31% (192 runs sampled)
> node benchmark/body1-1kb.js
1KB body
1 test completed.
2 tests completed.
3 tests completed.
4 tests completed.
buffer - strong x 263,069 ops/sec ±1.60% (190 runs sampled)
* buffer - weak x 295,732 ops/sec ±0.43% (199 runs sampled)
string - strong x 274,822 ops/sec ±1.15% (191 runs sampled)
string - weak x 169,473 ops/sec ±1.59% (194 runs sampled)
> node benchmark/body2-5kb.js
5KB body
1 test completed.
2 tests completed.
3 tests completed.
4 tests completed.
buffer - strong x 104,299 ops/sec ±0.60% (193 runs sampled)
* buffer - weak x 108,126 ops/sec ±0.65% (196 runs sampled)
string - strong x 101,736 ops/sec ±0.78% (194 runs sampled)
string - weak x 101,266 ops/sec ±0.85% (192 runs sampled)
> node benchmark/body3-10kb.js
10KB body
1 test completed.
2 tests completed.
3 tests completed.
4 tests completed.
buffer - strong x 59,007 ops/sec ±0.29% (198 runs sampled)
* buffer - weak x 60,968 ops/sec ±0.48% (197 runs sampled)
string - strong x 51,873 ops/sec ±1.78% (178 runs sampled)
string - weak x 52,307 ops/sec ±2.63% (193 runs sampled)
> node benchmark/body4-100kb.js
100KB body
1 test completed.
2 tests completed.
3 tests completed.
4 tests completed.
buffer - strong x 6,712 ops/sec ±0.11% (198 runs sampled)
* buffer - weak x 6,716 ops/sec ±0.50% (196 runs sampled)
string - strong x 6,397 ops/sec ±0.36% (196 runs sampled)
string - weak x 6,635 ops/sec ±0.15% (198 runs sampled)
```
## License
[MIT](LICENSE)
[npm-image]: https://img.shields.io/npm/v/etag.svg?style=flat
[npm-url]: https://npmjs.org/package/etag
[node-version-image]: https://img.shields.io/node/v/etag.svg?style=flat
[node-version-url]: http://nodejs.org/download/
[travis-image]: https://img.shields.io/travis/jshttp/etag.svg?style=flat
[travis-url]: https://travis-ci.org/jshttp/etag
[coveralls-image]: https://img.shields.io/coveralls/jshttp/etag.svg?style=flat
[coveralls-url]: https://coveralls.io/r/jshttp/etag?branch=master
[downloads-image]: https://img.shields.io/npm/dm/etag.svg?style=flat
[downloads-url]: https://npmjs.org/package/etag
|
