README
¶
consistent
🐶🐶
this package is consistent hash for golang.
install
go get github.com/dogslee/consistent
example
Lock at the godoc
status
This package is a stable version though. but is still a personal and experimental tool. It is friendly for developers with customization needs. Interested developers can change it with their extensive mathematical knowledge.
Thanks
😄
Documentation
¶
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Consistent ¶
type Consistent interface {
// Add provides the ability to add new nodes, returns an error message if the node does not exist.
Add(string) error
// Get returns the node corresponding to the current consistency hash
Get(string) (string, error)
// Del delete an already existing consistent hash node, returns an error message if the node does not exist.
Del(string) error
}
Consistent is the consistency hash interface, used to hide complex implementation details
func New ¶
func New() Consistent
New
Example ¶
package main
import (
"fmt"
"log"
"github.com/dogslee/consistent"
)
func main() {
// default consistent hash function
c := consistent.New()
// add new node
c.Add("node1")
c.Add("node2")
c.Add("node3")
c.Add("node4")
keyCase := []string{"user1", "user2", "user3", "user4"}
for _, k := range keyCase {
srvNode, err := c.Get(k)
if err != nil {
log.Fatal(err)
}
fmt.Printf("key: %s ==> srvNode: %s", k, srvNode)
}
}
Output: key: user1 ==> srvNode: node2 key: user2 ==> srvNode: node2 key: user3 ==> srvNode: node2 key: user4 ==> srvNode: node3
func NewOpt ¶
func NewOpt(opts ...Option) Consistent
NewOpt returns a custom set consistency hash. This defines the settings including: 1.the number of virtual node copies 2.basic string hash function 3.virtual node name generation rules
Example ¶
package main
import (
"fmt"
"hash/fnv"
"log"
"strconv"
"github.com/dogslee/consistent"
)
func main() {
// custom consistent hash functions
c := consistent.NewOpt(
// set virtual node
consistent.VirtualReplicas(50),
// set hashFunc
consistent.HashFunc(func(key string) (uint32, error) {
h := fnv.New32a()
h.Write([]byte(key))
return h.Sum32(), nil
}),
// set gen key rule
consistent.KeyRule(func(key string, idx int) (string, error) {
return key + strconv.Itoa(idx), nil
}))
c.Add("node1")
c.Add("node2")
c.Add("node3")
c.Add("node4")
keyCase := []string{"user10", "user20", "user30", "user40"}
for _, k := range keyCase {
srvNode, err := c.Get(k)
if err != nil {
log.Fatal(err)
}
fmt.Printf("key: %s ==> srvNode: %s\n", k, srvNode)
}
}
Output: key: user10 ==> srvNode: node3 key: user20 ==> srvNode: node1 key: user30 ==> srvNode: node2 key: user40 ==> srvNode: node2
type Option ¶
type Option func(o *consistent)
Option consistent hash setting function type
func KeyRule ¶
KeyRule set virtual node name generation rules. This function is generated by default as $key+"#"+string($idx)
func VirtualReplicas ¶
VirtualReplicas set the number of virtual node copies. This value defaults to 100
Source Files