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@1.2.0 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   502,914 ops/sec ±1.18% (185 runs sampled)
  buffer - weak   x 1,149,420 ops/sec ±0.48% (194 runs sampled)
  string - strong x   205,007 ops/sec ±2.08% (179 runs sampled)
  string - weak   x   356,944 ops/sec ±1.68% (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 293,298 ops/sec ±1.04% (190 runs sampled)
  buffer - weak   x 297,940 ops/sec ±0.23% (196 runs sampled)
  string - strong x 153,165 ops/sec ±2.02% (186 runs sampled)
  string - weak   x 169,967 ops/sec ±1.27% (187 runs sampled)

> node benchmark/body2-5kb.js

  5KB body

  1 test completed.
  2 tests completed.
  3 tests completed.
  4 tests completed.

  buffer - strong x 103,880 ops/sec ±0.62% (194 runs sampled)
  buffer - weak   x 104,204 ops/sec ±0.73% (192 runs sampled)
  string - strong x  58,025 ops/sec ±4.10% (185 runs sampled)
  string - weak   x  59,181 ops/sec ±3.96% (186 runs sampled)

> node benchmark/body3-10kb.js

  10KB body

  1 test completed.
  2 tests completed.
  3 tests completed.
  4 tests completed.

  buffer - strong x 57,975 ops/sec ±0.42% (195 runs sampled)
  buffer - weak   x 57,658 ops/sec ±0.48% (194 runs sampled)
  string - strong x 38,969 ops/sec ±3.44% (187 runs sampled)
  string - weak   x 38,979 ops/sec ±3.38% (187 runs sampled)

> node benchmark/body4-100kb.js

  100KB body

  1 test completed.
  2 tests completed.
  3 tests completed.
  4 tests completed.

  buffer - strong x 6,517 ops/sec ±0.18% (194 runs sampled)
  buffer - weak   x 6,484 ops/sec ±0.18% (194 runs sampled)
  string - strong x 5,115 ops/sec ±2.29% (190 runs sampled)
  string - weak   x 5,071 ops/sec ±2.32% (190 runs sampled)

License

MIT