hrw/README.md

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# Golang HRW implementation
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[Rendezvous or highest random weight](https://en.wikipedia.org/wiki/Rendezvous_hashing) (HRW) hashing is an algorithm that allows clients to achieve distributed agreement on a set of k options out of a possible set of n options. A typical application is when clients need to agree on which sites (or proxies) objects are assigned to. When k is 1, it subsumes the goals of consistent hashing, using an entirely different method.
## Install
`go get github.com/im-kulikov/hrw`
## Example
```go
package main
import (
"fmt"
"github.com/im-kulikov/hrw"
)
func main() {
// given a set of servers
servers := []string{
"one.example.com",
"two.example.com",
"three.example.com",
"four.example.com",
"five.example.com",
"six.example.com",
}
// HRW can consistently select a uniformly-distributed set of servers for
// any given key
var (
key = []byte("/examples/object-key")
h = hrw.Hash(key)
)
hrw.SortSliceByValue(servers, h)
for id := range servers {
fmt.Printf("trying GET %s%s\n", servers[id], key)
}
// Output:
// trying GET four.example.com/examples/object-key
// trying GET three.example.com/examples/object-key
// trying GET one.example.com/examples/object-key
// trying GET two.example.com/examples/object-key
// trying GET six.example.com/examples/object-key
// trying GET five.example.com/examples/object-key
}
```