diff --git a/.chglog/CHANGELOG.tpl.md b/.chglog/CHANGELOG.tpl.md
new file mode 100755
index 0000000..d08c458
--- /dev/null
+++ b/.chglog/CHANGELOG.tpl.md
@@ -0,0 +1,41 @@
+{{ if .Versions -}}
+
+
+{{ if .Unreleased.CommitGroups -}}
+{{ range .Unreleased.CommitGroups -}}
+### {{ .Title }}
+{{ range .Commits -}}
+- {{ if .Scope }}**{{ .Scope }}:** {{ end }}{{ .Subject }}
+{{ end }}
+{{ end -}}
+{{ end -}}
+{{ end -}}
+
+{{ range .Versions }}
+
+## {{ if .Tag.Previous }}[{{ .Tag.Name }}]{{ else }}{{ .Tag.Name }}{{ end }} - {{ datetime "2006-01-02" .Tag.Date }}
+{{ range .CommitGroups -}}
+### {{ .Title }}
+{{ range .Commits -}}
+- {{ if .Scope }}**{{ .Scope }}:** {{ end }}{{ .Subject }}
+{{ end }}
+{{ end -}}
+
+{{- if .NoteGroups -}}
+{{ range .NoteGroups -}}
+### {{ .Title }}
+{{ range .Notes }}
+{{ .Body }}
+{{ end }}
+{{ end -}}
+{{ end -}}
+{{ end -}}
+
+{{- if .Versions }}
+[Unreleased]: {{ .Info.RepositoryURL }}/compare/{{ $latest := index .Versions 0 }}{{ $latest.Tag.Name }}...HEAD
+{{ range .Versions -}}
+{{ if .Tag.Previous -}}
+[{{ .Tag.Name }}]: {{ $.Info.RepositoryURL }}/compare/{{ .Tag.Previous.Name }}...{{ .Tag.Name }}
+{{ end -}}
+{{ end -}}
+{{ end -}}
\ No newline at end of file
diff --git a/.chglog/config.yml b/.chglog/config.yml
new file mode 100755
index 0000000..ee1e4cd
--- /dev/null
+++ b/.chglog/config.yml
@@ -0,0 +1,27 @@
+style: github
+template: CHANGELOG.tpl.md
+info:
+ title: CHANGELOG
+ repository_url: https://github.com/miun173/rebalance
+options:
+ commits:
+ # filters:
+ # Type:
+ # - feat
+ # - fix
+ # - perf
+ # - refactor
+ commit_groups:
+ # title_maps:
+ # feat: Features
+ # fix: Bug Fixes
+ # perf: Performance Improvements
+ # refactor: Code Refactoring
+ header:
+ pattern: "^(\\w*)\\:\\s(.*)$"
+ pattern_maps:
+ - Type
+ - Subject
+ notes:
+ keywords:
+ - BREAKING CHANGE
\ No newline at end of file
diff --git a/.gitignore b/.gitignore
index 0dc7b4b..76203a6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
-/.vscode
\ No newline at end of file
+/.vscode
+/output
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..daeb1ce
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,10 @@
+
+
+
+
+## v0.1.0 - 2019-12-27
+### Feature
+- add round robin load balancer
+
+
+[Unreleased]: https://github.com/miun173/rebalance/compare/v0.1.0...HEAD
diff --git a/Makefile b/Makefile
index e1c83c5..0dd3817 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,24 @@
+bench_cmd := go test -run=^$ github.com/miun173/rebalance/${package} -bench=.
+run_cmd := go run cmd/*
+
+test:
+ go test -v -covermode=atomic ./...
+
run-proxy:
- @go run cmd/proxy/main.go
+ @$(run_cmd) proxy
run-sidecar:
- @go run cmd/sidecar/main.go $(args)
\ No newline at end of file
+ @$(run_cmd) sidecar join --url $(url) --service-ports $(service-ports)
+
+build:
+ @go build -ldflags="-w -s" -o output/rebalance ./cmd/...
+
+bench:
+ @cd proxy && $(bench_cmd)
+
+changelog:
+ifdef version
+ @git-chglog --next-tag $(version) -o CHANGELOG.md
+else
+ @git-chglog -o CHANGELOG.md
+endif
diff --git a/README.md b/README.md
index 501aab1..81f2363 100644
--- a/README.md
+++ b/README.md
@@ -3,6 +3,23 @@
Experimentation on server load balancing using Round Robin algorithm with self join.
## TODO
-- [ ] proxy request to several ip
- - [?] proxy request to an ip
-- [ ] add self join & discovery
\ No newline at end of file
+- [x] proxy request to several ip
+ - [x] proxy request to an ip
+- [ ] add self join & discovery
+ - [x] can join from proxied services
+- [x] handle concurrent proxy requests
+ - [reff](https://kasvith.github.io/posts/lets-create-a-simple-lb-go)
+
+# Benchmarks
+`$ make bench package=proxy`
+```
+goos: linux
+goarch: amd64
+pkg: github.com/miun173/rebalance/proxy
+Benchmark4Upstream/200_microsecond/response/1000_req-4 1000000000 0.87 ns/op
+Benchmark4Upstream/200_microsecond/response/10000_req-4 1 8659798397 ns/op
+Benchmark4Upstream/20_microsecond/response/1000_req-4 1000000000 0.87 ns/op
+Benchmark4Upstream/20_microsecond/response/10000_req-4 1 8673090255 ns/op
+PASS
+ok github.com/miun173/rebalance/proxy 79.571s
+```
diff --git a/cmd/main.go b/cmd/main.go
new file mode 100644
index 0000000..4985185
--- /dev/null
+++ b/cmd/main.go
@@ -0,0 +1,5 @@
+package main
+
+func main() {
+ rootCMD.Execute()
+}
diff --git a/cmd/root.go b/cmd/root.go
new file mode 100644
index 0000000..139ab77
--- /dev/null
+++ b/cmd/root.go
@@ -0,0 +1,78 @@
+package main
+
+import (
+ "errors"
+ "fmt"
+ "os"
+ "os/signal"
+ "strings"
+ "syscall"
+
+ "github.com/miun173/rebalance/proxy"
+ "github.com/miun173/rebalance/sidecar"
+ log "github.com/sirupsen/logrus"
+ "github.com/spf13/cobra"
+)
+
+var (
+ // used for flags
+ url string
+ servicePorts string
+
+ rootCMD = &cobra.Command{}
+ proxyCMD = &cobra.Command{
+ Use: "proxy",
+ Short: "a reverse proxy",
+ Run: runProxy,
+ }
+
+ sidecarCMD = &cobra.Command{
+ Use: "sidecar",
+ Short: "a sidecar proxy",
+ }
+
+ joinCMD = &cobra.Command{
+ Use: "join",
+ Short: "join a service into proxy",
+ Example: "join --url 'http://127.0.0.1:9000'",
+ Run: runJoinProxy,
+ }
+)
+
+func init() {
+ joinCMD.PersistentFlags().StringVar(&url, "url", "", "proxy service url")
+ joinCMD.PersistentFlags().StringVar(&servicePorts, "service-ports", "80", "services ports that will be proxied 80,8080,9000")
+
+ sidecarCMD.AddCommand(joinCMD)
+ rootCMD.AddCommand(sidecarCMD)
+ rootCMD.AddCommand(proxyCMD)
+}
+
+func runProxy(cmd *cobra.Command, args []string) {
+ fmt.Println("starting loadbalancer at :9000")
+
+ sp := proxy.NewServiceProxy()
+
+ signalCh := make(chan os.Signal, 1)
+ defer close(signalCh)
+
+ signal.Notify(signalCh, os.Interrupt, syscall.SIGINT, syscall.SIGTERM)
+
+ go sp.Start()
+ go sp.RunHealthCheck()
+
+ <-signalCh
+ log.Println("exiting...")
+}
+
+func runJoinProxy(cmd *cobra.Command, args []string) {
+ if url == "" {
+ log.Fatal(errors.New("url should be in form 'http://127.0.0.1:9000'"))
+ }
+
+ ports := strings.Split(servicePorts, ",")
+ sc := sidecar.NewSideCar(url)
+ if err := sc.Join(ports...); err != nil {
+ log.Fatal(err)
+ }
+}
diff --git a/go.mod b/go.mod
index 9fdb5cf..426109b 100644
--- a/go.mod
+++ b/go.mod
@@ -1,3 +1,9 @@
module github.com/miun173/rebalance
go 1.12
+
+require (
+ github.com/sirupsen/logrus v1.4.2
+ github.com/spf13/cobra v0.0.5
+ github.com/stretchr/testify v1.4.0
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..3095d3b
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,57 @@
+github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
+github.com/coreos/etcd v3.3.10+incompatible/go.mod h1:uF7uidLiAD3TWHmW31ZFd/JWoc32PjwdhPthX9715RE=
+github.com/coreos/go-etcd v2.0.0+incompatible/go.mod h1:Jez6KQU2B/sWsbdaef3ED8NzMklzPG4d5KIOhIy30Tk=
+github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
+github.com/cpuguy83/go-md2man v1.0.10/go.mod h1:SmD6nW6nTyfqj6ABTjUi3V3JVMnlJmwcJI5acqYI6dE=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
+github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
+github.com/hashicorp/hcl v1.0.0 h1:0Anlzjpi4vEasTeNFn2mLJgTSwt0+6sfsiTG8qcWGx4=
+github.com/hashicorp/hcl v1.0.0/go.mod h1:E5yfLk+7swimpb2L/Alb/PJmXilQ/rhwaUYs4T20WEQ=
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+github.com/magiconair/properties v1.8.0 h1:LLgXmsheXeRoUOBOjtwPQCWIYqM/LU1ayDtDePerRcY=
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+github.com/mitchellh/mapstructure v1.1.2 h1:fmNYVwqnSfB9mZU6OS2O6GsXM+wcskZDuKQzvN1EDeE=
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diff --git a/proxy/service.go b/proxy/service.go
new file mode 100644
index 0000000..922d9c4
--- /dev/null
+++ b/proxy/service.go
@@ -0,0 +1,39 @@
+package proxy
+
+import (
+ "net/http/httputil"
+ "net/url"
+ "sync"
+)
+
+// Service :nodoc:
+type Service struct {
+ Proxy *httputil.ReverseProxy
+ URL *url.URL
+ isAlive bool
+ mutex sync.RWMutex
+}
+
+// NewService :nodoc:
+func NewService(p *httputil.ReverseProxy, u *url.URL) *Service {
+ return &Service{
+ Proxy: p,
+ URL: u,
+ isAlive: true,
+ }
+}
+
+// SetAlive :nodoc:
+func (s *Service) SetAlive(alive bool) {
+ s.mutex.Lock()
+ s.isAlive = alive
+ s.mutex.Unlock()
+}
+
+// IsAlive :nodoc:
+func (s *Service) IsAlive() (alive bool) {
+ s.mutex.Lock()
+ alive = s.isAlive
+ s.mutex.Unlock()
+ return
+}
diff --git a/proxy/service_pool.go b/proxy/service_pool.go
new file mode 100644
index 0000000..4b84897
--- /dev/null
+++ b/proxy/service_pool.go
@@ -0,0 +1,263 @@
+package proxy
+
+import (
+ "context"
+ "encoding/json"
+ "errors"
+ "fmt"
+ "net"
+ "net/http"
+ "net/http/httputil"
+ "net/http/pprof"
+ "net/url"
+ "time"
+
+ // pprof
+ _ "net/http/pprof"
+
+ log "github.com/sirupsen/logrus"
+)
+
+type key int
+
+const (
+ _Attempts key = 0
+ _Retry key = 1
+
+ _MaxRetries int = 3
+ _MaxAttempt int = 3
+)
+
+// ServiceProxy :nodoc:
+type ServiceProxy struct {
+ mapURL map[string]string
+ services []*Service
+ currentService int
+}
+
+// NewServiceProxy :nodoc:
+func NewServiceProxy() *ServiceProxy {
+ return &ServiceProxy{
+ mapURL: make(map[string]string),
+ services: make([]*Service, 0),
+ }
+}
+
+// NextIndex :nodoc:
+func (sp *ServiceProxy) NextIndex() int {
+ return sp.currentService % len(sp.services)
+}
+
+// Start round robin server :nodoc:
+func (sp *ServiceProxy) Start() {
+ m := &http.ServeMux{}
+ m.HandleFunc("/", sp.Handler)
+ m.HandleFunc("/rebalance/join", sp.HandleJoin)
+
+ // Register pprof handlers
+ m.HandleFunc("/debug/pprof/", pprof.Index)
+ m.HandleFunc("/debug/pprof/cmdline", pprof.Cmdline)
+ m.HandleFunc("/debug/pprof/profile", pprof.Profile)
+ m.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
+ m.HandleFunc("/debug/pprof/trace", pprof.Trace)
+
+ if err := http.ListenAndServe(":9000", m); err != nil {
+ log.Fatal(err)
+ }
+}
+
+// AddServer :nodoc:
+func (sp *ServiceProxy) AddServer(targetURL string) error {
+ if _, ok := sp.mapURL[targetURL]; ok {
+ return errors.New("server url already added")
+ }
+
+ serviceURL, err := url.Parse(targetURL)
+ if err != nil {
+ return err
+ }
+
+ if ok := isServiceAlive(serviceURL); !ok {
+ return errors.New("cannot dial service")
+ }
+
+ sp.mapURL[targetURL] = targetURL
+
+ proxy := httputil.NewSingleHostReverseProxy(serviceURL)
+ transport := &http.Transport{
+ DisableCompression: true,
+ DisableKeepAlives: false,
+ MaxIdleConns: 100,
+ MaxIdleConnsPerHost: 100,
+ }
+ proxy.Transport = transport
+
+ sp.services = append(sp.services, NewService(proxy, serviceURL))
+
+ return nil
+}
+
+// getClientIP extracts the user IP address from req, if present.
+func getClientIP(req *http.Request) (net.IP, error) {
+ ip, _, err := net.SplitHostPort(req.RemoteAddr)
+ if err != nil {
+ return nil, fmt.Errorf("userip: %q is not IP:port", req.RemoteAddr)
+ }
+
+ userIP := net.ParseIP(ip)
+ if userIP == nil {
+ return nil, fmt.Errorf("userip: %q is not IP:port", req.RemoteAddr)
+ }
+ return userIP, nil
+}
+
+// HandleJoin :nodoc:
+func (sp *ServiceProxy) HandleJoin(w http.ResponseWriter, r *http.Request) {
+ ip, err := getClientIP(r)
+ if err != nil {
+ log.Fatal(err)
+ }
+
+ port := ":" + r.URL.Query().Get("port")
+
+ log.Println("requst join from host ", ip.String()+port)
+ if err := sp.AddServer("http://" + ip.String() + port); err != nil {
+ log.Error(err)
+ w.WriteHeader(http.StatusBadRequest)
+ resp, err := json.Marshal(map[string]interface{}{"error": err.Error()})
+ if err != nil {
+ log.Error(err)
+ w.WriteHeader(http.StatusInternalServerError)
+ return
+ }
+
+ w.Write(resp)
+ return
+ }
+
+ w.WriteHeader(http.StatusOK)
+ w.Write([]byte("success join"))
+}
+
+// FindNextService find next alive service
+func (sp *ServiceProxy) FindNextService() *Service {
+ if len(sp.services) == 0 {
+ return nil
+ }
+
+ next := sp.NextIndex()
+ n := len(sp.services) + next
+ nservice := len(sp.services)
+
+ for i := next; i < n; i++ {
+ idx := i % nservice
+ if sp.services[idx].IsAlive() {
+ sp.currentService = (sp.currentService + 1) % nservice
+ return sp.services[next]
+ }
+ }
+
+ return nil
+}
+
+// Handler :nodoc:
+func (sp *ServiceProxy) Handler(w http.ResponseWriter, r *http.Request) {
+ // if the same request routing for few attempts with different backends, increase the count
+ attempts := getRetryAttemptsFromCtx(r, _Attempts)
+ if attempts > 3 {
+ log.Printf("%s(%s) Max attempts reached, terminating\n", r.RemoteAddr, r.URL.Path)
+ http.Error(w, "Service not available", http.StatusServiceUnavailable)
+ return
+ }
+
+ service := sp.FindNextService()
+ if service == nil {
+ http.Error(w, "service not available", http.StatusServiceUnavailable)
+ return
+ }
+
+ service.Proxy.ErrorHandler = sp.ProxyErrorHandler(service)
+ service.Proxy.ServeHTTP(w, r)
+}
+
+// ProxyErrorHandler :nodoc:
+func (sp *ServiceProxy) ProxyErrorHandler(service *Service) func(w http.ResponseWriter, r *http.Request, err error) {
+ return func(w http.ResponseWriter, r *http.Request, err error) {
+ if err != nil {
+ log.Error(err)
+ }
+
+ retries := getRetryAttemptsFromCtx(r, _Retry)
+ if retries < _MaxRetries {
+ select {
+ case <-time.After(10 * time.Millisecond):
+ ctx := context.WithValue(r.Context(), _Retry, retries+1)
+ service.Proxy.ServeHTTP(w, r.WithContext(ctx))
+ }
+
+ return
+ }
+
+ service.SetAlive(false)
+
+ // if the same request routing for few attempts with different backends, increase the count
+ attempts := getRetryAttemptsFromCtx(r, _Attempts)
+ log.Printf("%s(%s) attempting retry %d\n", r.RemoteAddr, r.URL.Path, attempts)
+ service := sp.FindNextService()
+ if service == nil {
+ http.Error(w, "service not available", http.StatusInternalServerError)
+ return
+ }
+
+ ctx := context.WithValue(r.Context(), _Attempts, attempts+1)
+ sp.Handler(w, r.WithContext(ctx))
+ }
+}
+
+// HealthCheck check services health status
+// mark service as alive if helathy
+func (sp *ServiceProxy) HealthCheck() {
+ for _, s := range sp.services {
+ status := "up"
+ alive := isServiceAlive(s.URL)
+ s.SetAlive(alive)
+ if !alive {
+ status = "down"
+ }
+
+ log.Printf("%s [%s]\n", s.URL, status)
+ }
+}
+
+// RunHealthCheck run HealthCheck every 20 second
+func (sp *ServiceProxy) RunHealthCheck() {
+ t := time.NewTicker(20 * time.Second)
+ for {
+ select {
+ case <-t.C:
+ log.Println("Starting health check...")
+ sp.HealthCheck()
+ log.Println("Health check completed")
+ }
+ }
+}
+
+func getRetryAttemptsFromCtx(r *http.Request, retyAttempKey key) int {
+ if val, ok := r.Context().Value(retyAttempKey).(int); ok {
+ return val
+ }
+
+ return 0
+}
+
+func isServiceAlive(u *url.URL) bool {
+ timeout := 2 * time.Second
+ conn, err := net.DialTimeout("tcp", u.Host, timeout)
+ if err != nil {
+ log.Println("Site unreachable, error: ", err)
+ return false
+ }
+ _ = conn.Close()
+
+ return true
+}
diff --git a/proxy/service_pool_test.go b/proxy/service_pool_test.go
new file mode 100644
index 0000000..a651136
--- /dev/null
+++ b/proxy/service_pool_test.go
@@ -0,0 +1,114 @@
+package proxy
+
+import (
+ "fmt"
+ "io/ioutil"
+ "net/http"
+ "net/http/httptest"
+ "testing"
+ "time"
+
+ "github.com/stretchr/testify/assert"
+)
+
+func TestHandler(t *testing.T) {
+ up1 := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+ fmt.Fprint(w, "Hello, client 1")
+ }))
+
+ up2 := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+ fmt.Fprint(w, "Hello, client 2")
+ }))
+
+ up3 := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+ fmt.Fprint(w, "Hello, client 3")
+ }))
+
+ sp := NewServiceProxy()
+ sp.AddServer(up1.URL)
+ sp.AddServer(up2.URL)
+ sp.AddServer(up3.URL)
+
+ ts := httptest.NewServer(http.HandlerFunc(sp.Handler))
+ defer ts.Close()
+
+ for i := 1; i <= 3; i++ {
+ res, err := http.Get(ts.URL)
+ assert.NoError(t, err)
+
+ greeting, err := ioutil.ReadAll(res.Body)
+ res.Body.Close()
+ assert.NoError(t, err)
+
+ assert.Equal(t, fmt.Sprintf("Hello, client %d", i), string(greeting))
+ }
+
+ res, err := http.Get(ts.URL)
+ assert.NoError(t, err)
+
+ greeting, err := ioutil.ReadAll(res.Body)
+ res.Body.Close()
+ assert.NoError(t, err)
+
+ assert.Equal(t, "Hello, client 1", string(greeting))
+}
+
+func Benchmark4Upstream(b *testing.B) {
+ b.Run("200 microsecond/response", func(b *testing.B) {
+ sp := NewServiceProxy()
+ for i := 0; i < 4; i++ {
+ up := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+ time.Sleep(time.Microsecond * 200)
+ fmt.Fprint(w, fmt.Sprintf("Hello, client %d", i))
+ }))
+
+ sp.AddServer(up.URL)
+ }
+
+ ts := httptest.NewServer(http.HandlerFunc(sp.Handler))
+ defer ts.Close()
+
+ b.Run("1000 req", func(b *testing.B) {
+ for i := 0; i < 1000; i++ {
+ res, _ := http.Get(ts.URL)
+ res.Body.Close()
+ }
+ })
+
+ b.Run("10000 req", func(b *testing.B) {
+ for i := 0; i < 10000; i++ {
+ res, _ := http.Get(ts.URL)
+ res.Body.Close()
+ }
+ })
+ })
+
+ b.Run("20 microsecond/response", func(b *testing.B) {
+ sp := NewServiceProxy()
+ for i := 0; i < 4; i++ {
+ up := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+ time.Sleep(time.Microsecond * 200)
+ fmt.Fprint(w, fmt.Sprintf("Hello, client %d", i))
+ }))
+
+ sp.AddServer(up.URL)
+ }
+
+ ts := httptest.NewServer(http.HandlerFunc(sp.Handler))
+ defer ts.Close()
+
+ b.Run("1000 req", func(b *testing.B) {
+ for i := 0; i < 1000; i++ {
+ res, _ := http.Get(ts.URL)
+ res.Body.Close()
+ }
+ })
+
+ b.Run("10000 req", func(b *testing.B) {
+ for i := 0; i < 10000; i++ {
+ res, _ := http.Get(ts.URL)
+ res.Body.Close()
+ }
+ })
+ })
+}
diff --git a/sidecar/sidecar.go b/sidecar/sidecar.go
index 1679f8f..70a8b0c 100644
--- a/sidecar/sidecar.go
+++ b/sidecar/sidecar.go
@@ -2,11 +2,10 @@ package sidecar
import (
"errors"
+ "fmt"
"io/ioutil"
"log"
"net/http"
-
- "github.com/miun173/rebalance/sidecar/config"
)
// SideCar :nodoc:
@@ -20,8 +19,24 @@ func NewSideCar(balancerURL string) *SideCar {
}
// Join joind load balancer cluster
-func (sc *SideCar) Join() error {
- resp, err := http.Get(sc.balancerURL + "/rebalance/join?port=" + config.ClientServicePort())
+func (sc *SideCar) Join(ports ...string) error {
+ if len(ports) == 0 {
+ url := sc.balancerURL + "/rebalance/join?port=80"
+ return join(url)
+ }
+
+ for _, port := range ports {
+ url := fmt.Sprintf("%s%s", sc.balancerURL+"/rebalance/join?port=", port)
+ if err := join(url); err != nil {
+ return err
+ }
+ }
+
+ return nil
+}
+
+func join(url string) error {
+ resp, err := http.Get(url)
if err != nil {
return err
}