101 lines
2.1 KiB
Go
101 lines
2.1 KiB
Go
package main
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import (
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"encoding/json"
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"fmt"
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"io/ioutil"
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"math/rand"
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"net/http"
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"os"
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"path/filepath"
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shortuuid "github.com/lithammer/shortuuid/v3"
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log "github.com/sirupsen/logrus"
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)
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var (
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nodeID string
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nodes map[string]Node
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)
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func init() {
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nodes = make(map[string]Node)
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}
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type Node struct {
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ID string
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Addr string
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}
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func (n Node) String() string {
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return fmt.Sprintf("Node{ID: %s Addr: %s}", n.ID, n.Addr)
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}
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func genNodeID(path string) (string, error) {
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fn := filepath.Join(path, "id")
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uuid := shortuuid.New()
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if err := os.WriteFile(fn, []byte(uuid), 0644); err != nil {
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log.WithError(err).Error("error writing node id")
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return "", fmt.Errorf("error writing node id: %w", err)
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}
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return uuid, nil
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}
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func getNodeID(path string) (string, error) {
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fn := filepath.Join(path, "id")
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data, err := os.ReadFile(fn)
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if err != nil {
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log.WithError(err).Errorf("error reading node id: %s", fn)
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return "", fmt.Errorf("error reading node id: %s", err)
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}
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return string(data), nil
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}
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func getNodeIds() []string {
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var res []string
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for k := range nodes {
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res = append(res, k)
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}
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return res
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}
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// TODO: Add other node selection algorithms
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// For example: affinity+random selection
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func selectNode() Node {
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keys := getNodeIds()
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n := rand.Int() % len(keys)
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key := keys[n]
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return nodes[key]
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}
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func refreshNodes(addr string) error {
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uri := fmt.Sprintf("http://%s/nodes", addr)
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res, err := request(http.MethodGet, uri, nil, nil)
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if err != nil {
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log.WithError(err).Error("error making nodes request")
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return fmt.Errorf("error nodes metadata request: %w", err)
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}
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if res.StatusCode != 200 {
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log.WithField("Status", res.Status).Error("error making nodes request")
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return fmt.Errorf("error making nodes request: %s", res.Status)
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}
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defer res.Body.Close()
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data, err := ioutil.ReadAll(res.Body)
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if err != nil {
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log.WithError(err).Error("error reading nodes response")
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return fmt.Errorf("error reading nodes response: %w", err)
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}
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if err := json.Unmarshal(data, &nodes); err != nil {
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log.WithError(err).Error("error reading nodes response")
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return fmt.Errorf("error reading nodes response: %w", err)
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}
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return nil
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}
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