Merge pull request #1714 from DiceDB/arpitbbhayani

Reactivity Example - Leaderboard

Author: arpitbbhayani

docs/astro.config.mjs

@@ -40,6 +40,10 @@ export default defineConfig({
         {
           label: "Examples and Tutorials",
           items: [
+            {
+              label: "Leaderboard",
+              link: "https://github.com/DiceDB/dice/tree/master/examples/leaderboard-go",
+            },
             {
               label: "CLI Chatroom",
               link: "https://github.com/DiceDB/dice/tree/master/examples/chatroom-go",

docs/src/components/Footer.astro

@@ -60,6 +60,12 @@ const { stars } = await fetchRepoDetails();
           Examples
         </div>
         <p>
+          <a
+            href="https://github.com/DiceDB/dice/tree/master/examples/leaderboard-go"
+            target="_blank"
+          >
+            Leaderboard</a
+          >
           <a
             href="https://github.com/DiceDB/dice/tree/master/examples/chatroom-go"
             target="_blank"

docs/src/content/docs/get-started/hello-world-reactive.mdx

@@ -57,7 +57,10 @@ whenever the value of `k1` changes, but it is not just a change event, but the a
 This makes it really powerful and flexible to build real-time applications.
 
 > Note: In CLI, you can watch one command at a time, but programmatically you can watch multiple commands at the same time
-> and handle them in parallel. You can take a look at our [Chatroom](https://github.com/DiceDB/dice/tree/master/examples/chatroom-go) to see how to do that.
+> and handle them in parallel. You can take a look at the following examples to see how to do that
+>
+> - [Chatroom](https://github.com/DiceDB/dice/tree/master/examples/chatroom-go)
+> - [Leaderboard](https://github.com/DiceDB/dice/tree/master/examples/leaderboard-go)
 
 ## What else can I watch?
 

docs/src/content/docs/get-started/hello-world.mdx

@@ -17,7 +17,7 @@ You can follow the steps mentioned in the [installation](/get-started/installati
 Once the DiceDB server starts, you will see output similar to this
 
 ```
-        ██████╗ ██╗ ██████╗███████╗██████╗ ██████╗ 
+        ██████╗ ██╗ ██████╗███████╗██████╗ ██████╗
         ██╔══██╗██║██╔════╝██╔════╝██╔══██╗██╔══██╗
         ██║  ██║██║██║     █████╗  ██║  ██║██████╔╝
         ██║  ██║██║██║     ██╔══╝  ██║  ██║██╔══██╗
@@ -54,7 +54,7 @@ then retrieve it using the [`GET`](/commands/get) command.
 
 ```bash
 localhost:7379> SET k1 v1
-OK 
+OK
 localhost:7379> GET k1
 OK "v1"
 ```
@@ -73,5 +73,7 @@ Note: The first `OK` is the status of the command, while the second `OK` is the
 This is just the tip of the iceberg when it comes to DiceDB.
 We've covered the basics of connecting to a DiceDB instance, storing a simple string, and retrieving it.
 The true power of DiceDB lies in its ability to intuitively build reactive applications
-like [chatrooms](https://github.com/DiceDB/dice/tree/master/examples/chatroom-go), handle complex data structures and perform operations efficiently.
+like [chatrooms](https://github.com/DiceDB/dice/tree/master/examples/chatroom-go) and
+[leaderboards](https://github.com/DiceDB/dice/tree/master/examples/leaderboard-go),
+handle complex data structures and perform operations efficiently.
 But all of that after we do our first tutorial for reactivity and query subscriptions.

examples/leaderboard-go/README.md

@@ -0,0 +1,15 @@
+Leaderboard
+===
+
+1. start the DiceDB server
+2. run the following command from one terminal session
+
+```sh
+$ go run main.go mock
+```
+
+3. run the following command from 3 other terminal sessions
+
+```sh
+$ go run main.go
+```

examples/leaderboard-go/go.mod

@@ -0,0 +1,30 @@
+module leaderboard-go
+
+go 1.24.0
+
+require (
+	github.com/charmbracelet/bubbles v0.20.0
+	github.com/charmbracelet/lipgloss v1.0.0
+	github.com/dicedb/dicedb-go v1.0.9
+)
+
+require (
+	github.com/aymanbagabas/go-osc52/v2 v2.0.1 // indirect
+	github.com/charmbracelet/bubbletea v1.2.4 // indirect
+	github.com/charmbracelet/x/ansi v0.4.5 // indirect
+	github.com/charmbracelet/x/term v0.2.1 // indirect
+	github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f // indirect
+	github.com/google/uuid v1.6.0 // indirect
+	github.com/lucasb-eyer/go-colorful v1.2.0 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/mattn/go-localereader v0.0.1 // indirect
+	github.com/mattn/go-runewidth v0.0.16 // indirect
+	github.com/muesli/ansi v0.0.0-20230316100256-276c6243b2f6 // indirect
+	github.com/muesli/cancelreader v0.2.2 // indirect
+	github.com/muesli/termenv v0.15.2 // indirect
+	github.com/rivo/uniseg v0.4.7 // indirect
+	golang.org/x/sync v0.9.0 // indirect
+	golang.org/x/sys v0.27.0 // indirect
+	golang.org/x/text v0.3.8 // indirect
+	google.golang.org/protobuf v1.36.5 // indirect
+)

examples/leaderboard-go/go.sum

@@ -0,0 +1,51 @@
+github.com/aymanbagabas/go-osc52/v2 v2.0.1 h1:HwpRHbFMcZLEVr42D4p7XBqjyuxQH5SMiErDT4WkJ2k=
+github.com/aymanbagabas/go-osc52/v2 v2.0.1/go.mod h1:uYgXzlJ7ZpABp8OJ+exZzJJhRNQ2ASbcXHWsFqH8hp8=
+github.com/charmbracelet/bubbles v0.20.0 h1:jSZu6qD8cRQ6k9OMfR1WlM+ruM8fkPWkHvQWD9LIutE=
+github.com/charmbracelet/bubbles v0.20.0/go.mod h1:39slydyswPy+uVOHZ5x/GjwVAFkCsV8IIVy+4MhzwwU=
+github.com/charmbracelet/bubbletea v1.2.4 h1:KN8aCViA0eps9SCOThb2/XPIlea3ANJLUkv3KnQRNCE=
+github.com/charmbracelet/bubbletea v1.2.4/go.mod h1:Qr6fVQw+wX7JkWWkVyXYk/ZUQ92a6XNekLXa3rR18MM=
+github.com/charmbracelet/lipgloss v1.0.0 h1:O7VkGDvqEdGi93X+DeqsQ7PKHDgtQfF8j8/O2qFMQNg=
+github.com/charmbracelet/lipgloss v1.0.0/go.mod h1:U5fy9Z+C38obMs+T+tJqst9VGzlOYGj4ri9reL3qUlo=
+github.com/charmbracelet/x/ansi v0.4.5 h1:LqK4vwBNaXw2AyGIICa5/29Sbdq58GbGdFngSexTdRM=
+github.com/charmbracelet/x/ansi v0.4.5/go.mod h1:dk73KoMTT5AX5BsX0KrqhsTqAnhZZoCBjs7dGWp4Ktw=
+github.com/charmbracelet/x/term v0.2.1 h1:AQeHeLZ1OqSXhrAWpYUtZyX1T3zVxfpZuEQMIQaGIAQ=
+github.com/charmbracelet/x/term v0.2.1/go.mod h1:oQ4enTYFV7QN4m0i9mzHrViD7TQKvNEEkHUMCmsxdUg=
+github.com/dicedb/dicedb-go v1.0.9 h1:WtXtX6Bu/KFjhnOIlnoo9Z1hbmOtL2tMrUmS6793/Pw=
+github.com/dicedb/dicedb-go v1.0.9/go.mod h1:V1fiCJnPfSObKWrOJ/zrhHEGlLwT9k3pKCto3sz1oW8=
+github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f h1:Y/CXytFA4m6baUTXGLOoWe4PQhGxaX0KpnayAqC48p4=
+github.com/erikgeiser/coninput v0.0.0-20211004153227-1c3628e74d0f/go.mod h1:vw97MGsxSvLiUE2X8qFplwetxpGLQrlU1Q9AUEIzCaM=
+github.com/google/go-cmp v0.5.5 h1:Khx7svrCpmxxtHBq5j2mp/xVjsi8hQMfNLvJFAlrGgU=
+github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/lucasb-eyer/go-colorful v1.2.0 h1:1nnpGOrhyZZuNyfu1QjKiUICQ74+3FNCN69Aj6K7nkY=
+github.com/lucasb-eyer/go-colorful v1.2.0/go.mod h1:R4dSotOR9KMtayYi1e77YzuveK+i7ruzyGqttikkLy0=
+github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
+github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/mattn/go-localereader v0.0.1 h1:ygSAOl7ZXTx4RdPYinUpg6W99U8jWvWi9Ye2JC/oIi4=
+github.com/mattn/go-localereader v0.0.1/go.mod h1:8fBrzywKY7BI3czFoHkuzRoWE9C+EiG4R1k4Cjx5p88=
+github.com/mattn/go-runewidth v0.0.16 h1:E5ScNMtiwvlvB5paMFdw9p4kSQzbXFikJ5SQO6TULQc=
+github.com/mattn/go-runewidth v0.0.16/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
+github.com/muesli/ansi v0.0.0-20230316100256-276c6243b2f6 h1:ZK8zHtRHOkbHy6Mmr5D264iyp3TiX5OmNcI5cIARiQI=
+github.com/muesli/ansi v0.0.0-20230316100256-276c6243b2f6/go.mod h1:CJlz5H+gyd6CUWT45Oy4q24RdLyn7Md9Vj2/ldJBSIo=
+github.com/muesli/cancelreader v0.2.2 h1:3I4Kt4BQjOR54NavqnDogx/MIoWBFa0StPA8ELUXHmA=
+github.com/muesli/cancelreader v0.2.2/go.mod h1:3XuTXfFS2VjM+HTLZY9Ak0l6eUKfijIfMUZ4EgX0QYo=
+github.com/muesli/termenv v0.15.2 h1:GohcuySI0QmI3wN8Ok9PtKGkgkFIk7y6Vpb5PvrY+Wo=
+github.com/muesli/termenv v0.15.2/go.mod h1:Epx+iuz8sNs7mNKhxzH4fWXGNpZwUaJKRS1noLXviQ8=
+github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
+github.com/rivo/uniseg v0.4.7 h1:WUdvkW8uEhrYfLC4ZzdpI2ztxP1I582+49Oc5Mq64VQ=
+github.com/rivo/uniseg v0.4.7/go.mod h1:FN3SvrM+Zdj16jyLfmOkMNblXMcoc8DfTHruCPUcx88=
+go.uber.org/mock v0.5.1 h1:ASgazW/qBmR+A32MYFDB6E2POoTgOwT509VP0CT/fjs=
+go.uber.org/mock v0.5.1/go.mod h1:ge71pBPLYDk7QIi1LupWxdAykm7KIEFchiOqd6z7qMM=
+golang.org/x/sync v0.9.0 h1:fEo0HyrW1GIgZdpbhCRO0PkJajUS5H9IFUztCgEo2jQ=
+golang.org/x/sync v0.9.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+golang.org/x/sys v0.0.0-20210809222454-d867a43fc93e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.27.0 h1:wBqf8DvsY9Y/2P8gAfPDEYNuS30J4lPHJxXSb/nJZ+s=
+golang.org/x/sys v0.27.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/text v0.3.8 h1:nAL+RVCQ9uMn3vJZbV+MRnydTJFPf8qqY42YiA6MrqY=
+golang.org/x/text v0.3.8/go.mod h1:E6s5w1FMmriuDzIBO73fBruAKo1PCIq6d2Q6DHfQ8WQ=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+google.golang.org/protobuf v1.36.5 h1:tPhr+woSbjfYvY6/GPufUoYizxw1cF/yFoxJ2fmpwlM=
+google.golang.org/protobuf v1.36.5/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=

examples/leaderboard-go/main.go

@@ -0,0 +1,61 @@
+// Copyright (c) 2022-present, DiceDB contributors
+// All rights reserved. Licensed under the BSD 3-Clause License. See LICENSE file in the project root for full license information.
+
+package main
+
+import (
+	"fmt"
+	"leaderboard-go/svc"
+	"math/rand"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
+	"github.com/dicedb/dicedb-go/wire"
+)
+
+var players = []string{"Alice", "Bob", "Charlie", "Dora", "Evan", "Fay", "Gina"}
+
+func main() {
+	if len(os.Args) > 1 && os.Args[1] == "mock" {
+		for {
+			player := players[rand.Intn(len(players))]
+			score := rand.Intn(100)
+			svc.UpdateScore(player, score)
+			fmt.Println("updated game:scores for", player, "with score", score)
+			time.Sleep(time.Millisecond * 500)
+		}
+	}
+
+	// Set up signal handling for graceful shutdown
+	sigChan := make(chan os.Signal, 1)
+	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
+
+	// Subscribe to leaderboard updates
+	svc.Subscribe()
+
+	// Start listening for messages
+	go svc.ListenForMessages(func(result *wire.Result) {
+		displayLeaderboard(result.GetZRANGERes().Elements)
+	})
+
+	// Wait for interrupt signal
+	<-sigChan
+	fmt.Println("\nShutting down...")
+}
+
+func displayLeaderboard(leaderboard []*wire.ZElement) {
+	// Clear the screen
+	fmt.Print("\033[H\033[2J")
+
+	fmt.Println("Rank  Score  Player")
+	fmt.Println("------------------")
+
+	for _, element := range leaderboard {
+		fmt.Printf("%2d.   %4d   %s\n", element.Rank, element.Score, element.Member)
+	}
+
+	fmt.Println("------------------")
+	fmt.Println("Press Ctrl+C to exit")
+}

examples/leaderboard-go/svc/main.go

@@ -0,0 +1,58 @@
+// Copyright (c) 2022-present, DiceDB contributors
+// All rights reserved. Licensed under the BSD 3-Clause License. See LICENSE file in the project root for full license information.
+
+package svc
+
+import (
+	"fmt"
+	"strconv"
+
+	"github.com/dicedb/dicedb-go"
+	"github.com/dicedb/dicedb-go/wire"
+)
+
+var (
+	client *dicedb.Client
+)
+
+func init() {
+	var err error
+	client, err = dicedb.NewClient("localhost", 7379)
+	if err != nil {
+		panic(err)
+	}
+}
+
+func UpdateScore(player string, score int) {
+	resp := client.Fire(&wire.Command{
+		Cmd:  "ZADD",
+		Args: []string{"game:scores", strconv.Itoa(score), player},
+	})
+	if resp.Status == wire.Status_ERR {
+		fmt.Println("error updating score:", resp.Message)
+	}
+}
+
+func Subscribe() {
+	resp := client.Fire(&wire.Command{
+		Cmd:  "ZRANGE.WATCH",
+		Args: []string{"game:scores", "1", "5", "BYRANK"},
+	})
+	if resp.Status == wire.Status_ERR {
+		fmt.Println("error subscribing:", resp.Message)
+	}
+}
+
+func ListenForMessages(onMessage func(result *wire.Result)) {
+	ch, err := client.WatchCh()
+	if err != nil {
+		panic(err)
+	}
+	for resp := range ch {
+		if resp.Status == wire.Status_ERR {
+			fmt.Println("error listening for messages:", resp.Message)
+		} else {
+			onMessage(resp)
+		}
+	}
+}

internal/cmd/cmd_get_watch.go

@@ -71,7 +71,7 @@ func evalGETWATCH(c *Cmd, s *dstore.Store) (*CmdRes, error) {
 }
 
 func executeGETWATCH(c *Cmd, sm *shardmanager.ShardManager) (*CmdRes, error) {
-	if len(c.C.Args) != 1 {
+	if len(c.C.Args) == 0 {
 		return GETWATCHResNilRes, errors.ErrWrongArgumentCount("GET.WATCH")
 	}
 	shard := sm.GetShardForKey(c.C.Args[0])