Add "--strategy" parameter to "bind-service" command

* see https://github.com/cloudfoundry/community/blob/main/toc/rfc/rfc-0040-service-binding-rotation.md#cf-cli

Author: jochenehret

actor/v7action/service_app_binding.go

@@ -15,6 +15,7 @@ type CreateServiceAppBindingParams struct {
 	AppName             string
 	BindingName         string
 	Parameters          types.OptionalObject
+	Strategy            resources.BindingStrategyType
 }
 
 type DeleteServiceAppBindingParams struct {
@@ -41,7 +42,7 @@ func (actor Actor) CreateServiceAppBinding(params CreateServiceAppBindingParams)
 			return
 		},
 		func() (warnings ccv3.Warnings, err error) {
-			jobURL, warnings, err = actor.createServiceAppBinding(serviceInstance.GUID, app.GUID, params.BindingName, params.Parameters)
+			jobURL, warnings, err = actor.createServiceAppBinding(serviceInstance.GUID, app.GUID, params.BindingName, params.Parameters, params.Strategy)
 			return
 		},
 		func() (warnings ccv3.Warnings, err error) {
@@ -102,13 +103,14 @@ func (actor Actor) DeleteServiceAppBinding(params DeleteServiceAppBindingParams)
 	}
 }
 
-func (actor Actor) createServiceAppBinding(serviceInstanceGUID, appGUID, bindingName string, parameters types.OptionalObject) (ccv3.JobURL, ccv3.Warnings, error) {
+func (actor Actor) createServiceAppBinding(serviceInstanceGUID, appGUID, bindingName string, parameters types.OptionalObject, strategy resources.BindingStrategyType) (ccv3.JobURL, ccv3.Warnings, error) {
 	jobURL, warnings, err := actor.CloudControllerClient.CreateServiceCredentialBinding(resources.ServiceCredentialBinding{
 		Type:                resources.AppBinding,
 		Name:                bindingName,
 		ServiceInstanceGUID: serviceInstanceGUID,
 		AppGUID:             appGUID,
 		Parameters:          parameters,
+		Strategy:            strategy,
 	})
 	switch err.(type) {
 	case nil:

actor/v7action/service_app_binding_test.go

@@ -35,6 +35,7 @@ var _ = Describe("Service App Binding Action", func() {
 			bindingName         = "fake-binding-name"
 			spaceGUID           = "fake-space-guid"
 			fakeJobURL          = ccv3.JobURL("fake-job-url")
+			strategy            = "single"
 		)
 
 		var (
@@ -87,6 +88,7 @@ var _ = Describe("Service App Binding Action", func() {
 				Parameters: types.NewOptionalObject(map[string]interface{}{
 					"foo": "bar",
 				}),
+				Strategy: resources.SingleBindingStrategy,
 			}
 		})
 
@@ -202,6 +204,7 @@ var _ = Describe("Service App Binding Action", func() {
 					Parameters: types.NewOptionalObject(map[string]interface{}{
 						"foo": "bar",
 					}),
+					Strategy: strategy,
 				}))
 			})
 

command/flag/service_binding_strategy.go

@@ -0,0 +1,30 @@
+package flag
+
+import (
+	"strings"
+
+	"code.cloudfoundry.org/cli/v8/resources"
+	flags "github.com/jessevdk/go-flags"
+)
+
+type ServiceBindingStrategy struct {
+	Strategy resources.BindingStrategyType
+}
+
+func (ServiceBindingStrategy) Complete(prefix string) []flags.Completion {
+	return completions([]string{"single", "multiple"}, prefix, false)
+}
+
+func (h *ServiceBindingStrategy) UnmarshalFlag(val string) error {
+	valLower := strings.ToLower(val)
+	switch valLower {
+	case "single", "multiple":
+		h.Strategy = resources.BindingStrategyType(valLower)
+	default:
+		return &flags.Error{
+			Type:    flags.ErrRequired,
+			Message: `STRATEGY must be "single" or "multiple"`,
+		}
+	}
+	return nil
+}

command/flag/service_binding_strategy_test.go

@@ -0,0 +1,61 @@
+package flag_test
+
+import (
+	. "code.cloudfoundry.org/cli/v8/command/flag"
+	"code.cloudfoundry.org/cli/v8/resources"
+	flags "github.com/jessevdk/go-flags"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("ServiceBindingStrategy", func() {
+	var sbs ServiceBindingStrategy
+
+	Describe("Complete", func() {
+		DescribeTable("returns list of completions",
+			func(prefix string, matches []flags.Completion) {
+				completions := sbs.Complete(prefix)
+				Expect(completions).To(Equal(matches))
+			},
+			Entry("returns 'single' when passed 's'", "s",
+				[]flags.Completion{{Item: "single"}}),
+			Entry("returns 'single' when passed 'S'", "S",
+				[]flags.Completion{{Item: "single"}}),
+			Entry("returns 'multiple' when passed 'm'", "m",
+				[]flags.Completion{{Item: "multiple"}}),
+			Entry("returns 'multiple' when passed 'M'", "M",
+				[]flags.Completion{{Item: "multiple"}}),
+			Entry("returns 'single' and 'multiple' when passed ''", "",
+				[]flags.Completion{{Item: "single"}, {Item: "multiple"}}),
+		)
+	})
+
+	Describe("UnmarshalFlag", func() {
+		BeforeEach(func() {
+			sbs = ServiceBindingStrategy{}
+		})
+
+		DescribeTable("downcases and sets strategy",
+			func(input string, expected resources.BindingStrategyType) {
+				err := sbs.UnmarshalFlag(input)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(sbs.Strategy).To(Equal(expected))
+			},
+			Entry("sets 'single' when passed 'single'", "single", resources.SingleBindingStrategy),
+			Entry("sets 'single' when passed 'sInGlE'", "sInGlE", resources.SingleBindingStrategy),
+			Entry("sets 'multiple' when passed 'multiple'", "multiple", resources.MultipleBindingStrategy),
+			Entry("sets 'multiple' when passed 'MuLtIpLe'", "MuLtIpLe", resources.MultipleBindingStrategy),
+		)
+
+		When("passed anything else", func() {
+			It("returns an error", func() {
+				err := sbs.UnmarshalFlag("banana")
+				Expect(err).To(MatchError(&flags.Error{
+					Type:    flags.ErrRequired,
+					Message: `STRATEGY must be "single" or "multiple"`,
+				}))
+				Expect(sbs.Strategy).To(BeEmpty())
+			})
+		})
+	})
+})

command/v7/bind_service_command.go

@@ -11,11 +11,12 @@ import (
 type BindServiceCommand struct {
 	BaseCommand
 
-	RequiredArgs     flag.BindServiceArgs          `positional-args:"yes"`
-	BindingName      flag.BindingName              `long:"binding-name" description:"Name to expose service instance to app process with (Default: service instance name)"`
-	ParametersAsJSON flag.JSONOrFileWithValidation `short:"c" description:"Valid JSON object containing service-specific configuration parameters, provided either in-line or in a file. For a list of supported configuration parameters, see documentation for the particular service offering."`
-	Wait             bool                          `short:"w" long:"wait" description:"Wait for the operation to complete"`
-	relatedCommands  interface{}                   `related_commands:"services"`
+	RequiredArgs           flag.BindServiceArgs          `positional-args:"yes"`
+	BindingName            flag.BindingName              `long:"binding-name" description:"Name to expose service instance to app process with (Default: service instance name)"`
+	ParametersAsJSON       flag.JSONOrFileWithValidation `short:"c" description:"Valid JSON object containing service-specific configuration parameters, provided either in-line or in a file. For a list of supported configuration parameters, see documentation for the particular service offering."`
+	ServiceBindingStrategy flag.ServiceBindingStrategy   `long:"strategy" description:"Service binding strategy. Valid values are 'single' (default) and 'multiple'."`
+	Wait                   bool                          `short:"w" long:"wait" description:"Wait for the operation to complete"`
+	relatedCommands        interface{}                   `related_commands:"services"`
 }
 
 func (cmd BindServiceCommand) Execute(args []string) error {
@@ -33,6 +34,7 @@ func (cmd BindServiceCommand) Execute(args []string) error {
 		AppName:             cmd.RequiredArgs.AppName,
 		BindingName:         cmd.BindingName.Value,
 		Parameters:          types.OptionalObject(cmd.ParametersAsJSON),
+		Strategy:            cmd.ServiceBindingStrategy.Strategy,
 	})
 	cmd.UI.DisplayWarnings(warnings)
 
@@ -82,7 +84,12 @@ Example of valid JSON object:
 
 Optionally provide a binding name for the association between an app and a service instance:
 
-CF_NAME bind-service APP_NAME SERVICE_INSTANCE --binding-name BINDING_NAME`
+CF_NAME bind-service APP_NAME SERVICE_INSTANCE --binding-name BINDING_NAME
+
+Optionally provide the binding strategy type. Valid options are 'single' (default) and 'multiple'. The 'multiple' strategy allows multiple bindings between the same app and service instance.
+This is useful for credential rotation scenarios.
+
+CF_NAME bind-service APP_NAME SERVICE_INSTANCE --strategy multiple`
 }
 
 func (cmd BindServiceCommand) Examples() string {

resources/service_credential_binding_resource.go

@@ -12,6 +12,13 @@ const (
 	KeyBinding ServiceCredentialBindingType = "key"
 )
 
+type BindingStrategyType string
+
+const (
+	SingleBindingStrategy   BindingStrategyType = "single"
+	MultipleBindingStrategy BindingStrategyType = "multiple"
+)
+
 type ServiceCredentialBinding struct {
 	// Type is either "app" or "key"
 	Type ServiceCredentialBindingType `jsonry:"type,omitempty"`
@@ -31,6 +38,8 @@ type ServiceCredentialBinding struct {
 	LastOperation LastOperation `jsonry:"last_operation"`
 	// Parameters can be specified when creating a binding
 	Parameters types.OptionalObject `jsonry:"parameters"`
+	// Strategy can be "single" (default) or "multiple"
+	Strategy BindingStrategyType `jsonry:"strategy,omitempty"`
 }
 
 func (s ServiceCredentialBinding) MarshalJSON() ([]byte, error) {

resources/service_credential_binding_resource_test.go

@@ -60,6 +60,15 @@ var _ = Describe("service credential binding resource", func() {
 				}
 			}`,
 		),
+		Entry(
+			"strategy",
+			ServiceCredentialBinding{
+				Strategy: SingleBindingStrategy,
+			},
+			`{
+				"strategy": "single"
+			}`,
+		),
 		Entry(
 			"everything",
 			ServiceCredentialBinding{
@@ -71,6 +80,7 @@ var _ = Describe("service credential binding resource", func() {
 				Parameters: types.NewOptionalObject(map[string]interface{}{
 					"foo": "bar",
 				}),
+				Strategy: MultipleBindingStrategy,
 			},
 			`{
 				"type": "app",
@@ -90,7 +100,8 @@ var _ = Describe("service credential binding resource", func() {
 				},
 				"parameters": {
 					"foo": "bar"
-				}
+				},
+				"strategy": "multiple"
 			}`,
 		),
 	)