Merge pull request #217 from zgalor/autoscaling

* Add autoscling to ocm cli

Commands updated:
ocm list machinepools - added autoscaling field, and range
ocm create cluster - added autoscaling params
ocm describe cluster - added autoscaling indication and range
ocm edit machinepool - can now edit default machine pool - and autoscaling params
ocm edit cluster - no longer able to edit compute nodes

cmd/ocm/cluster/create/create.go

@@ -231,7 +231,7 @@ func run(cmd *cobra.Command, argv []string) error {
 	// Print the result:
 	cluster = response.Body()
 
-	err = clusterpkg.PrintClusterDesctipion(connection, cluster)
+	err = clusterpkg.PrintClusterDescription(connection, cluster)
 	if err != nil {
 		return err
 	}

cmd/ocm/cluster/describe/describe.go

@@ -152,7 +152,7 @@ func run(cmd *cobra.Command, argv []string) error {
 		}
 
 	} else {
-		err = clusterpkg.PrintClusterDesctipion(connection, cluster)
+		err = clusterpkg.PrintClusterDescription(connection, cluster)
 		if err != nil {
 			return err
 		}

cmd/ocm/create/cluster/cmd.go

@@ -58,6 +58,7 @@ var args struct {
 	// Scaling options
 	computeMachineType string
 	computeNodes       int
+	autoscaling        c.Autoscaling
 
 	// Networking options
 	hostPrefix  int
@@ -178,6 +179,7 @@ func init() {
 			minComputeNodes(false, true), minComputeNodes(true, true),
 		),
 	)
+	arguments.AddAutoscalingFlags(fs, &args.autoscaling)
 
 	fs.IPNetVar(
 		&args.machineCIDR,
@@ -378,15 +380,27 @@ func preRun(cmd *cobra.Command, argv []string) error {
 		return err
 	}
 
-	// Default compute nodes:
-	if args.computeNodes == 0 {
-		args.computeNodes = minComputeNodes(args.ccs.Enabled, args.multiAZ)
+	err = promptAutoscaling(fs)
+	if err != nil {
+		return err
 	}
-	err = arguments.PromptInt(fs, "compute-nodes", validateComputeNodes)
+
+	err = arguments.CheckIgnoredAutoscalingFlags(args.autoscaling, args.computeNodes)
 	if err != nil {
 		return err
 	}
 
+	if !args.autoscaling.Enabled {
+		// Default compute nodes:
+		if args.computeNodes == 0 {
+			args.computeNodes = minComputeNodes(args.ccs.Enabled, args.multiAZ)
+		}
+		err = arguments.PromptInt(fs, "compute-nodes", validateComputeNodes)
+		if err != nil {
+			return err
+		}
+	}
+
 	err = promptNetwork(fs)
 	if err != nil {
 		return err
@@ -422,6 +436,7 @@ func run(cmd *cobra.Command, argv []string) error {
 		Expiration:         expiration,
 		ComputeMachineType: args.computeMachineType,
 		ComputeNodes:       args.computeNodes,
+		Autoscaling:        args.autoscaling,
 		MachineCIDR:        args.machineCIDR,
 		ServiceCIDR:        args.serviceCIDR,
 		PodCIDR:            args.podCIDR,
@@ -440,7 +455,7 @@ func run(cmd *cobra.Command, argv []string) error {
 			fmt.Println("dry run: Would be successful.")
 		}
 	} else {
-		err = c.PrintClusterDesctipion(connection, cluster)
+		err = c.PrintClusterDescription(connection, cluster)
 		if err != nil {
 			return err
 		}
@@ -540,6 +555,30 @@ func validateComputeNodes() error {
 	return nil
 }
 
+func validateAutoscalingMin() error {
+	min := minComputeNodes(args.ccs.Enabled, args.multiAZ)
+
+	if args.autoscaling.MinReplicas < min {
+		return fmt.Errorf("Minimum is %d nodes", min)
+	}
+
+	if args.multiAZ && args.autoscaling.MinReplicas%3 != 0 {
+		return fmt.Errorf("Multi AZ clusters require that the number of compute nodes be a multiple of 3")
+	}
+	return nil
+}
+
+func validateAutoscalingMax() error {
+	if args.autoscaling.MinReplicas > args.autoscaling.MaxReplicas {
+		return fmt.Errorf("max-replicas must be greater or equal to min-replicas")
+	}
+
+	if args.multiAZ && args.autoscaling.MaxReplicas%3 != 0 {
+		return fmt.Errorf("Multi AZ clusters require that the number of compute nodes be a multiple of 3")
+	}
+	return nil
+}
+
 func fetchFlavours(client *cmv1.Client) (flavours []*cmv1.Flavour, err error) {
 	collection := client.Flavours()
 	page := 1
@@ -576,3 +615,27 @@ func constructGCPCredentials(filePath arguments.FilePath, value *c.CCS) error {
 	}
 	return nil
 }
+
+func promptAutoscaling(fs *pflag.FlagSet) error {
+	err := arguments.PromptBool(fs, "enable-autoscaling")
+	if err != nil {
+		return err
+	}
+	if args.autoscaling.Enabled {
+		// set default
+		args.autoscaling.MinReplicas = minComputeNodes(args.ccs.Enabled, args.multiAZ)
+		err = arguments.PromptInt(fs, "min-replicas", validateAutoscalingMin)
+		if err != nil {
+			return err
+		}
+
+		// set default
+		args.autoscaling.MaxReplicas = args.autoscaling.MinReplicas
+		err = arguments.PromptInt(fs, "max-replicas", validateAutoscalingMax)
+		if err != nil {
+			return err
+		}
+
+	}
+	return nil
+}

cmd/ocm/create/machinepool/cmd.go

@@ -29,6 +29,7 @@ var args struct {
 	clusterKey   string
 	instanceType string
 	replicas     int
+	autoscaling  c.Autoscaling
 	labels       string
 	taints       string
 }
@@ -40,6 +41,9 @@ var Cmd = &cobra.Command{
 	Long:    "Add a machine pool to the cluster.",
 	Example: `  # Add a machine pool mp-1 with 3 replicas and m5.xlarge instance type to a cluster
   ocm create machinepool --cluster mycluster --instance-type m5.xlarge --replicas 3 mp-1
+  # Add a machine pool mp-1 with autoscaling enabled and 3 to 6 replicas of m5.xlarge to a cluster
+  ocm create machinepool --cluster=mycluster --name=mp-1 --enable-autoscaling \
+  --min-replicas=3 --max-replicas=6 --instance-type=m5.xlarge
   # Add a machine pool mp-1 with labels and m5.xlarge instance type to a cluster
   ocm create machinepool --cluster mycluster --instance-type m5.xlarge --replicas 3 --labels "foo=bar,bar=baz" mp-1
   # Add a machine pool mp-1 with taints and m5.xlarge instance type to a cluster
@@ -77,8 +81,7 @@ func init() {
 		"Count of machines for this machine pool.",
 	)
 
-	//nolint:gosec
-	Cmd.MarkFlagRequired("replicas")
+	arguments.AddAutoscalingFlags(flags, &args.autoscaling)
 
 	flags.StringVar(
 		&args.labels,
@@ -138,6 +141,28 @@ func run(cmd *cobra.Command, argv []string) error {
 		}
 	}
 
+	isMinReplicasSet := cmd.Flags().Changed("min-replicas")
+	isMaxReplicasSet := cmd.Flags().Changed("max-replicas")
+	isReplicasSet := cmd.Flags().Changed("replicas")
+
+	if args.autoscaling.Enabled {
+		if isReplicasSet {
+			return fmt.Errorf("--replicas is only allowed when --enable-autoscaling=false")
+		}
+
+		if !isMaxReplicasSet || !isMinReplicasSet {
+			return fmt.Errorf("Both --min-replicas and --max-replicas are required when --enable-autoscaling=true")
+		}
+	} else {
+		if !isReplicasSet {
+			return fmt.Errorf("--replicas is required when --enable-autoscaling=false")
+		}
+
+		if isMaxReplicasSet || isMinReplicasSet {
+			return fmt.Errorf("--min-replicas and --max-replicas are not allowed when --enable-autoscaling=false")
+		}
+	}
+
 	// Create the client for the OCM API:
 	connection, err := ocm.NewConnection().Build()
 	if err != nil {
@@ -167,13 +192,22 @@ func run(cmd *cobra.Command, argv []string) error {
 		return err
 	}
 
-	machinePool, err := cmv1.NewMachinePool().ID(machinePoolID).
+	mpBuilder := cmv1.NewMachinePool().
+		ID(machinePoolID).
 		InstanceType(args.instanceType).
-		Replicas(args.replicas).
 		Labels(labels).
-		Taints(taintBuilders...).
-		Build()
+		Taints(taintBuilders...)
+
+	if args.autoscaling.Enabled {
+		mpBuilder = mpBuilder.Autoscaling(
+			cmv1.NewMachinePoolAutoscaling().
+				MinReplicas(args.autoscaling.MinReplicas).
+				MaxReplicas(args.autoscaling.MaxReplicas))
+	} else {
+		mpBuilder = mpBuilder.Replicas(args.replicas)
+	}
 
+	machinePool, err := mpBuilder.Build()
 	if err != nil {
 		return fmt.Errorf("Failed to create machine pool for cluster '%s': %v", clusterKey, err)
 	}

cmd/ocm/describe/cluster/cmd.go

@@ -151,7 +151,7 @@ func run(cmd *cobra.Command, argv []string) error {
 		}
 
 	} else {
-		err = clusterpkg.PrintClusterDesctipion(connection, cluster)
+		err = clusterpkg.PrintClusterDescription(connection, cluster)
 		if err != nil {
 			return err
 		}

cmd/ocm/edit/cluster/cmd.go

@@ -30,9 +30,6 @@ var args struct {
 	expirationTime     string
 	expirationDuration time.Duration
 
-	// Scaling options
-	computeNodes int
-
 	// Networking options
 	private bool
 }
@@ -79,15 +76,6 @@ func init() {
 	//nolint:gosec
 	flags.MarkHidden("expiration")
 
-	// Scaling options
-	flags.IntVar(
-		&args.computeNodes,
-		"compute-nodes",
-		0,
-		"Number of worker nodes to provision per zone. Single zone clusters need at least 4 nodes, "+
-			"while multizone clusters need at least 9 nodes (3 per zone) for resiliency.",
-	)
-
 	// Networking options
 	flags.BoolVar(
 		&args.private,
@@ -137,15 +125,9 @@ func run(cmd *cobra.Command, argv []string) error {
 		private = &args.private
 	}
 
-	var computeNodes int
-	if cmd.Flags().Changed("compute-nodes") {
-		computeNodes = args.computeNodes
-	}
-
 	clusterConfig := c.Spec{
-		Expiration:   expiration,
-		ComputeNodes: computeNodes,
-		Private:      private,
+		Expiration: expiration,
+		Private:    private,
 	}
 	err = c.UpdateCluster(clusterCollection, cluster.ID(), clusterConfig)
 	if err != nil {