Package Exports

etag

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (etag) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

etag

Create simple ETags

Installation

$ npm install etag

API

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, Buffers, 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).

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

$ npm test

Benchmark

$ npm run-script bench

> etag@1.6.0 bench nodejs-etag
> node benchmark/index.js

  http_parser@1.0
  node@0.10.33
  v8@3.14.5.9
  ares@1.9.0-DEV
  uv@0.10.29
  zlib@1.2.3
  modules@11
  openssl@1.0.1j

> 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