Adds check-health command to temporal-cassandra-tool and switches sta…

…rt.sh to use that instead of cqlsh (#885)

There are two changes:

Add check-health to the temporal-cassandra-tool. This enables us to test connectivity to a Cassandra Cluster using username, password and any TLS settings.
Switch startup.sh to use this new check-health command instead of cqlsh for auto-setup.
This change will enable auto-setup to work against a Cassandra DB configured with TLS or username/password when launching from the docker-compose file.

Tested auto-setup locally and the check-health command against a deployed Cassandra environment with username/password and mTLS enabled.

Low risk change

docker/start.sh

@@ -100,8 +100,16 @@ setup_schema() {
 }
 
 wait_for_cassandra() {
-    server=`echo $CASSANDRA_SEEDS | awk -F ',' '{print $1}'`
-    until cqlsh --cqlversion=3.4.4 $server < /dev/null; do
+    export CASSANDRA_USER=$CASSANDRA_USER
+    export CASSANDRA_PORT=$CASSANDRA_PORT
+    export CASSANDRA_ENABLE_TLS=$CASSANDRA_TLS_ENABLED
+    export CASSANDRA_TLS_CERT=$CASSANDRA_CERT
+    export CASSANDRA_TLS_KEY=$CASSANDRA_CERT_KEY
+    export CASSANDRA_TLS_CA=$CASSANDRA_CA
+
+    { export CASSANDRA_PASSWORD=$CASSANDRA_PASSWORD; } 2> /dev/null
+
+    until temporal-cassandra-tool --ep $CASSANDRA_SEEDS validate-health < /dev/null; do
         echo 'waiting for cassandra to start up'
         sleep 1
     done

tools/cassandra/handler.go

@@ -138,7 +138,6 @@ func updateSchema(cli *cli.Context) error {
 	return nil
 }
 
-// createKeyspace creates a cassandra Keyspace
 func createKeyspace(cli *cli.Context) error {
 	config, err := newCQLClientConfig(cli)
 	if err != nil {
@@ -150,11 +149,28 @@ func createKeyspace(cli *cli.Context) error {
 	}
 	err = doCreateKeyspace(*config, keyspace)
 	if err != nil {
-		return handleErr(fmt.Errorf("error creating Keyspace:%v", err))
+		return handleErr(fmt.Errorf("error creating Keyspace:%+v", err))
 	}
 	return nil
 }
 
+func validateHealth(cli *cli.Context) error {
+	config, err := newCQLClientConfig(cli)
+	if err != nil {
+		return handleErr(schema.NewConfigError(err.Error()))
+	}
+
+	config.Keyspace = systemKeyspace
+
+	client, err := newCQLClient(config)
+	if err != nil {
+		return handleErr(fmt.Errorf("unable to establish CQL session:%+v", err))
+	}
+
+	defer client.Close()
+	return nil
+}
+
 func doCreateKeyspace(cfg CQLClientConfig, name string) error {
 	cfg.Keyspace = systemKeyspace
 	client, err := newCQLClient(&cfg)

tools/cassandra/main.go

@@ -204,6 +204,14 @@ func buildCLIOptions() *cli.App {
 				cliHandler(c, createKeyspace)
 			},
 		},
+		{
+			Name:    "validate-health",
+			Aliases: []string{"vh"},
+			Usage:   "validates health of cassandra by attempting to establish CQL session to system keyspace",
+			Action: func(c *cli.Context) {
+				cliHandler(c, validateHealth)
+			},
+		},
 	}
 
 	return app