playgroud: support kv-only mode to start TiKV cluster only (#1333)

components/playground/main.go

@@ -55,6 +55,7 @@ type bootOptions struct {
 	drainer instance.Config
 	host    string
 	monitor bool
+	kvOnly  bool
 }
 
 func installIfMissing(profile *localdata.Profile, component, version string) error {
@@ -78,7 +79,7 @@ func installIfMissing(profile *localdata.Profile, component, version string) err
 func execute() error {
 	opt := &bootOptions{
 		tidb: instance.Config{
-			Num:       1,
+			Num:       -1,
 			UpTimeout: 60,
 		},
 		tikv: instance.Config{
@@ -88,7 +89,7 @@ func execute() error {
 			Num: 1,
 		},
 		tiflash: instance.Config{
-			Num:       1,
+			Num:       -1,
 			UpTimeout: 120,
 		},
 		host:    "127.0.0.1",
@@ -105,8 +106,9 @@ Examples:
   $ tiup playground nightly                         # Start a TiDB nightly version local cluster
   $ tiup playground v3.0.10 --db 3 --pd 3 --kv 3    # Start a local cluster with 10 nodes
   $ tiup playground nightly --monitor=false         # Start a local cluster and disable monitor system
-  $ tiup playground --pd.config ~/config/pd.toml    # Start a local cluster with specified configuration file,
-  $ tiup playground --db.binpath /xx/tidb-server    # Start a local cluster with component binary path`,
+  $ tiup playground --pd.config ~/config/pd.toml    # Start a local cluster with specified configuration file
+  $ tiup playground --db.binpath /xx/tidb-server    # Start a local cluster with component binary path
+  $ tiup playground --kv-mode --pd 3 --kv 3 		# Start a local cluster in KV mode (No TiDB Available)`,
 		SilenceUsage:  true,
 		SilenceErrors: true,
 		Version:       version.NewTiUPVersion().String(),
@@ -212,6 +214,7 @@ Examples:
 	rootCmd.Flags().StringVarP(&opt.tidb.Host, "db.host", "", opt.tidb.Host, "Playground TiDB host. If not provided, TiDB will still use `host` flag as its host")
 	rootCmd.Flags().StringVarP(&opt.pd.Host, "pd.host", "", opt.pd.Host, "Playground PD host. If not provided, PD will still use `host` flag as its host")
 	rootCmd.Flags().BoolVar(&opt.monitor, "monitor", opt.monitor, "Start prometheus and grafana component")
+	rootCmd.Flags().BoolVar(&opt.kvOnly, "kv-only", opt.kvOnly, "If start a TiKV cluster only")
 
 	rootCmd.Flags().StringVarP(&opt.tidb.ConfigPath, "db.config", "", opt.tidb.ConfigPath, "TiDB instance configuration file")
 	rootCmd.Flags().StringVarP(&opt.tikv.ConfigPath, "kv.config", "", opt.tikv.ConfigPath, "TiKV instance configuration file")

components/playground/playground.go

@@ -667,6 +667,21 @@ func (p *Playground) bootCluster(ctx context.Context, env *environment.Environme
 
 	p.bootOptions = options
 
+	// If the startup mode is not kv-only mode, set the default count of TiDB instances to 1.
+	switch {
+	case options.kvOnly:
+		if options.tidb.Num > 0 || options.tiflash.Num > 0 || options.pump.Num > 0 || options.drainer.Num > 0 {
+			return fmt.Errorf("in kv-only mode, TiDB related component are not allowed")
+		}
+		options.tidb.Num = 0
+		options.tiflash.Num = 0
+	case options.tidb.Num < 0:
+		options.tidb.Num = 1
+		fallthrough
+	case options.tiflash.Num < 0:
+		options.tiflash.Num = 1
+	}
+
 	if options.pd.Num < 1 || options.tikv.Num < 1 {
 		return fmt.Errorf("all components count must be great than 0 (tikv=%v, pd=%v)", options.tikv.Num, options.pd.Num)
 	}