Squashed commit of the following:

commit 4827425146
Author: chrislu <chris.lu@gmail.com>
Date:   Sat Sep 16 15:05:38 2023 -0700

    balancer works

commit 3b50139f68
Author: chrislu <chris.lu@gmail.com>
Date:   Fri Sep 15 22:22:32 2023 -0700

    comments

commit 7f685ce7ba
Author: chrislu <chris.lu@gmail.com>
Date:   Fri Sep 15 22:20:05 2023 -0700

    adjust APIs

commit 436d99443b
Author: chrislu <chris.lu@gmail.com>
Date:   Thu Sep 14 23:49:05 2023 -0700

    receive broker stats

commit b771fefa37
Merge: 0a851ec00 890881037
Author: chrislu <chris.lu@gmail.com>
Date:   Wed Sep 13 00:03:47 2023 -0700

    Merge branch 'master' into sub

commit 0a851ec00b
Author: chrislu <chris.lu@gmail.com>
Date:   Sun Sep 10 22:01:25 2023 -0700

    Create balancer.go

commit 39941edc0b
Author: chrislu <chris.lu@gmail.com>
Date:   Thu Sep 7 23:55:19 2023 -0700

    add publisher shutdown

commit 875f562779
Author: chrislu <chris.lu@gmail.com>
Date:   Wed Sep 6 23:16:41 2023 -0700

    server side send response at least once per second

commit 984b6c54cf
Author: chrislu <chris.lu@gmail.com>
Date:   Wed Sep 6 23:15:29 2023 -0700

    ack interval 128

commit 2492a45499
Author: chrislu <chris.lu@gmail.com>
Date:   Wed Sep 6 22:39:46 2023 -0700

    ack interval

commit ba67e6ca29
Author: chrislu <chris.lu@gmail.com>
Date:   Mon Sep 4 21:43:50 2023 -0700

    api for sub

commit 9e4f985698
Author: chrislu <chris.lu@gmail.com>
Date:   Mon Sep 4 21:43:30 2023 -0700

    publish, benchmark

commit cb470d44df
Author: chrislu <chris.lu@gmail.com>
Date:   Fri Sep 1 00:36:51 2023 -0700

    can pub and sub

commit 1eb2da46d5
Author: chrislu <chris.lu@gmail.com>
Date:   Mon Aug 28 09:02:12 2023 -0700

    connect and publish

commit 504ae8383a
Author: chrislu <chris.lu@gmail.com>
Date:   Mon Aug 28 09:01:25 2023 -0700

    protoc version

commit dbcba75271
Author: chrislu <chris.lu@gmail.com>
Date:   Sun Aug 27 18:59:04 2023 -0700

    rename to lookup

commit c9caf33119
Author: chrislu <chris.lu@gmail.com>
Date:   Sun Aug 27 18:33:46 2023 -0700

    move functions

commit 4d6c18d86f
Author: chrislu <chris.lu@gmail.com>
Date:   Sun Aug 27 17:50:59 2023 -0700

    pub sub initial tests

commit 4eb8e8624d
Author: chrislu <chris.lu@gmail.com>
Date:   Sun Aug 27 13:14:39 2023 -0700

    rename

commit 1990456670
Author: chrislu <chris.lu@gmail.com>
Date:   Sun Aug 27 13:13:14 2023 -0700

    sub

commit 905911853d
Author: chrislu <chris.lu@gmail.com>
Date:   Sat Aug 26 13:39:21 2023 -0700

    adjust proto

weed/mq/client/cmd/weed_pub/publisher.go

@@ -0,0 +1,58 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"github.com/seaweedfs/seaweedfs/weed/mq/client/pub_client"
+	"log"
+	"sync"
+	"time"
+)
+
+var (
+	messageCount = flag.Int("n", 1000, "message count")
+	concurrency  = flag.Int("c", 4, "concurrency count")
+)
+
+func doPublish(publisher *pub_client.TopicPublisher, id int) {
+	startTime := time.Now()
+	for i := 0; i < *messageCount / *concurrency; i++ {
+		// Simulate publishing a message
+		key := []byte(fmt.Sprintf("key-%d-%d", id, i))
+		value := []byte(fmt.Sprintf("value-%d-%d", id, i))
+		publisher.Publish(key, value) // Call your publisher function here
+		// println("Published", string(key), string(value))
+	}
+	elapsed := time.Since(startTime)
+	log.Printf("Publisher %d finished in %s", id, elapsed)
+}
+
+func main() {
+	flag.Parse()
+	publisher := pub_client.NewTopicPublisher(
+		"test", "test")
+	if err := publisher.Connect("localhost:17777"); err != nil {
+		fmt.Println(err)
+		return
+	}
+
+	startTime := time.Now()
+
+	// Start multiple publishers
+	var wg sync.WaitGroup
+	for i := 0; i < *concurrency; i++ {
+		wg.Add(1)
+		go func(id int) {
+			defer wg.Done()
+			doPublish(publisher, id)
+		}(i)
+	}
+
+	// Wait for all publishers to finish
+	wg.Wait()
+	elapsed := time.Since(startTime)
+	publisher.Shutdown()
+
+	log.Printf("Published %d messages in %s (%.2f msg/s)", *messageCount, elapsed, float64(*messageCount)/elapsed.Seconds())
+
+}

weed/mq/client/cmd/weed_sub/subscriber.go

@@ -0,0 +1,44 @@
+package main
+
+import (
+	"fmt"
+	"github.com/seaweedfs/seaweedfs/weed/mq/client/sub_client"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials/insecure"
+)
+
+func main() {
+
+	subscriberConfig := &sub_client.SubscriberConfiguration{
+		ClientId:        "testSubscriber",
+		GroupId:         "test",
+		GroupInstanceId: "test",
+		GrpcDialOption:  grpc.WithTransportCredentials(insecure.NewCredentials()),
+	}
+
+	contentConfig := &sub_client.ContentConfiguration{
+		Namespace: "test",
+		Topic:     "test",
+		Filter:    "",
+	}
+
+	subscriber := sub_client.NewTopicSubscriber(subscriberConfig, contentConfig)
+	if err := subscriber.Connect("localhost:17777"); err != nil {
+		fmt.Println(err)
+		return
+	}
+
+	subscriber.SetEachMessageFunc(func(key, value []byte) bool {
+		println(string(key), "=>", string(value))
+		return true
+	})
+
+	subscriber.SetCompletionFunc(func() {
+		println("done subscribing")
+	})
+
+	if err := subscriber.Subscribe(); err != nil {
+		fmt.Println(err)
+	}
+
+}