remove rq

rpcx/internal/balancer/roundrobin.go

@@ -2,15 +2,16 @@ package balancer
 
 import (
 	"context"
+	"math/rand"
+	"sync"
+	"time"
 
 	"google.golang.org/grpc/balancer"
 	"google.golang.org/grpc/balancer/base"
 	"google.golang.org/grpc/resolver"
 )
 
-const (
-	Name = "roundrobin"
-)
+const Name = "roundrobin"
 
 func init() {
 	balancer.Register(newBuilder())
@@ -24,13 +25,38 @@ func newBuilder() balancer.Builder {
 }
 
 func (b *roundRobinPickerBuilder) Build(readySCs map[resolver.Address]balancer.SubConn) balancer.Picker {
-	panic("implement me")
+	rand.Seed(time.Now().UnixNano())
+	picker := &roundRobinPicker{
+		index: rand.Int(),
+	}
+
+	for addr, conn := range readySCs {
+		picker.conns = append(picker.conns, &subConn{
+			addr: addr,
+			conn: conn,
+		})
+	}
+
+	return picker
 }
 
 type roundRobinPicker struct {
+	conns []*subConn
+	index int
+	lock  sync.Mutex
 }
 
 func (p *roundRobinPicker) Pick(ctx context.Context, info balancer.PickInfo) (
 	conn balancer.SubConn, done func(balancer.DoneInfo), err error) {
-	panic("implement me")
+	p.lock.Lock()
+	defer p.lock.Unlock()
+
+	p.index = (p.index + 1) % len(p.conns)
+	return p.conns[p.index].conn, func(info balancer.DoneInfo) {
+	}, nil
+}
+
+type subConn struct {
+	addr resolver.Address
+	conn balancer.SubConn
 }

rpcx/internal/resolver/resolver.go

@@ -3,6 +3,7 @@ package resolver
 import "google.golang.org/grpc/resolver"
 
 type discovResolver struct {
+	cc resolver.ClientConn
 }
 
 func (r discovResolver) ResolveNow(options resolver.ResolveNowOptions) {