chore: make sha1 the default algo (#98)

* chore: make sha1 the default algo

* re-mention fnv1a

* update default test

* fix typo

* make linter happy

README.md

@@ -41,22 +41,24 @@ app.listen(3000)
 
 ## Plugin Options
 
-* `algorithm`: all hashing algorithm that Node.js support, and
-  `'fnv1a'`. Default: `'fnv1a'`.
+* `algorithm`: all hashing algorithms the Node.js [`crypto`](https://nodejs.org/api/crypto.html) module supports, and `'fnv1a'. Default: `'sha1'`.
 
 * `weak`: generates weak ETags by default. Default: `false`.
 
 ## Acknowledgements
 
-The fnv1a logic was forked from https://github.com/sindresorhus/fnv1a
-and adapted to support buffers.
+The fnv1a logic was forked from https://github.com/sindresorhus/fnv1a and adapted to support buffers.
 
 ## Benchmarks
 
-* `md5` algorithm: 29679 req/s (median)
-* `sha1` algorithm: 25935 req/s (median)
-* `fnv1a` algorithm: 42943 req/s (median)
-* No ETag generation: 45471 req/s (median)
+Generating an etag will always be slower than not generating an etag. The generation speed also depends on the payload size and type (buffer or string):
+
+* For very small payloads (< 2 kb), use `'fnv1a'`
+* For buffers above 2 mb, use `'md5'`
+* In all other scenarios, use `'sha1'` (default)
+* YMMV, see [this issue](https://github.com/fastify/fastify-etag/issues/91) where other algorithms such as crc32 for small payloads and murmurhash3-wasm for big buffers have performed better than the mentioned recommendations
+* Any etag generation results in at least 10% less op/s (up to 50% less op/s for huge payloads)
+
 
 ## License
 

index.js

@@ -17,7 +17,7 @@ function validateAlgorithm (algorithm) {
   }
 }
 
-function buildHashFn (algorithm = 'fnv1a', weak = false) {
+function buildHashFn (algorithm = 'sha1', weak = false) {
   validateAlgorithm(algorithm)
 
   const prefix = weak ? 'W/"' : '"'
@@ -26,7 +26,7 @@ function buildHashFn (algorithm = 'fnv1a', weak = false) {
   }
 
   return (payload) => prefix + createHash(algorithm)
-    .update(payload).digest().toString('base64') + '"'
+    .update(payload).digest('base64') + '"'
 }
 
 async function fastifyEtag (app, opts) {

test/basic.test.js

@@ -36,8 +36,8 @@ test('weak fnv1a', async (t) => {
   })
 })
 
-test('default -> fnv1a', async (t) => {
+test('default -> sha1', async (t) => {
   generic(t, {}, (body) => {
-    return '"' + fnv1a(body).toString(36) + '"'
+    return '"' + createHash('sha1').update(body).digest().toString('base64') + '"'
   })
 })