93 lines
1.8 KiB
Go
93 lines
1.8 KiB
Go
package client
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import (
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"bytes"
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"errors"
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"io/ioutil"
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"log"
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"net"
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"net/http"
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"strings"
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"github.com/buraksezer/consistent"
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"github.com/cespare/xxhash"
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)
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type Client struct {
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hash *consistent.Consistent
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}
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type hasher struct{}
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func (h hasher) Sum64(data []byte) uint64 {
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return xxhash.Sum64(data)
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}
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type netAddr string
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func (na netAddr) String() string {
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return string(na)
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}
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func (na netAddr) Network() string {
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return "tcp"
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}
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func New(addrs ...string) (*Client, error) {
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cfg := consistent.Config{
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PartitionCount: 71,
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ReplicationFactor: 20,
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Load: 1.25,
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Hasher: hasher{},
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}
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hash := consistent.New(nil, cfg)
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for _, addr := range addrs {
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hash.Add(netAddr(addr))
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}
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for _, addr := range hash.GetMembers() {
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conn, err := net.Dial("tcp", strings.TrimPrefix(strings.TrimPrefix(addr.String(), "http://"), "https://"))
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if err != nil {
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return nil, err
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}
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conn.Close()
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}
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return &Client{
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hash: hash,
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}, nil
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}
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func (c *Client) Get(key string) ([]byte, error) {
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addr := c.hash.LocateKey([]byte(key)).String()
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log.Printf("GET %s FROM %s", key, addr)
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resp, err := http.Get(addr + "/" + key)
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if err != nil {
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return nil, err
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}
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defer resp.Body.Close()
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if resp.StatusCode == http.StatusNotFound {
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return nil, nil
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}
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if resp.StatusCode != http.StatusOK {
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return nil, errors.New("bad status on get")
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}
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return ioutil.ReadAll(resp.Body)
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}
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func (c *Client) Set(key string, value []byte) error {
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addr := c.hash.LocateKey([]byte(key)).String()
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log.Printf("SET %s FROM %s", key, addr)
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r, err := http.NewRequest("PUT", addr+"/"+key, bytes.NewBuffer(value))
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if err != nil {
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return err
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}
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resp, err := (&http.Client{}).Do(r)
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if err != nil {
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return err
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}
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defer resp.Body.Close()
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if resp.StatusCode != http.StatusOK {
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return errors.New("bad status on set")
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}
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return nil
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}
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