#145 : Added support for COMMAND COUNT command

core/commands.go

@@ -303,6 +303,11 @@ var (
 		Info: "Quit the server",
 		Eval: nil,
 	}
+	commandCmdMeta = DiceCmdMeta{
+		Name: "COMMAND <subcommand>",
+		Info: "Evaluates COMMAND <subcommand> command based on subcommand",
+		Eval: evalCommand,
+	}
 )
 
 func init() {
@@ -346,4 +351,5 @@ func init() {
 	diceCmds["EXEC"] = execCmdMeta
 	diceCmds["DISCARD"] = discardCmdMeta
 	diceCmds["ABORT"] = abortCmdMeta
+	diceCmds["COMMAND"] = commandCmdMeta
 }

core/eval.go

@@ -4,13 +4,12 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
+	"github.com/dicedb/dice/config"
 	"log"
 	"strconv"
 	"strings"
 	"syscall"
 	"time"
-
-	"github.com/dicedb/dice/config"
 )
 
 var RESP_NIL []byte = []byte("$-1\r\n")
@@ -24,8 +23,10 @@ var RESP_EMPTY_ARRAY []byte = []byte("*0\r\n")
 
 var txnCommands map[string]bool
 var serverID string
+var diceCommandsCount int
 
 func init() {
+	diceCommandsCount = len(diceCmds)
 	txnCommands = map[string]bool{"EXEC": true, "DISCARD": true}
 	serverID = fmt.Sprintf("%s:%d", config.Host, config.Port)
 }
@@ -857,6 +858,26 @@ func evalQWATCH(args []string, c *Client) []byte {
 	return RESP_OK
 }
 
+// evalCommand evaluates COMMAND <subcommand> command based on subcommand
+// COUNT: return total count of commands in Dice.
+func evalCommand(args []string) []byte {
+	if len(args) == 0 {
+		return Encode(errors.New("(error) ERR wrong number of arguments for 'command' command"), false)
+	}
+	subcommand := strings.ToUpper(args[0])
+	switch subcommand {
+	case "COUNT":
+		return evalCommandCount(nil)
+	default:
+		return Encode(fmt.Errorf("ERR unknown subcommand '%s'. Try COMMAND HELP", subcommand), false)
+	}
+}
+
+// evalCommandCount returns an number of commands supported by DiceDB
+func evalCommandCount(args []string) []byte {
+	return Encode(diceCommandsCount, false)
+}
+
 func executeCommand(cmd *RedisCmd, c *Client) []byte {
 	diceCmd, ok := diceCmds[cmd.Cmd]
 	if !ok {

tests/command_count_test.go

@@ -0,0 +1,36 @@
+package tests
+
+import (
+	"fmt"
+	"gotest.tools/v3/assert"
+	"net"
+	"testing"
+)
+
+func TestCommandCount(t *testing.T) {
+	connection := getLocalConnection()
+	commandCount := getCommandCount(connection)
+	if commandCount <= 0 {
+		t.Fail()
+	}
+	assert.Assert(t, commandCount > 0,
+		fmt.Sprintf("Unexpected number of CLI commands found. expected greater than 0, %d found", commandCount))
+}
+
+func getCommandCount(connection net.Conn) int64 {
+	responseValue := fireCommand(connection, "COMMAND COUNT")
+	if responseValue == nil {
+		return -1
+	}
+	return responseValue.(int64)
+}
+
+func BenchmarkCountCommand(b *testing.B) {
+	connection := getLocalConnection()
+	for n := 0; n < b.N; n++ {
+		commandCount := getCommandCount(connection)
+		if commandCount <= 0 {
+			b.Fail()
+		}
+	}
+}