Dynamic registration of Kanister functions with multiple versions (#371)

* Changes to register functions with versions

* Add unit test

* Func signature changes in tests

* Add version to actionsets in e2e tests

* Address review comments and add more unit tests

pkg/controller/controller.go

@@ -381,7 +381,7 @@ func (c *Controller) runAction(ctx context.Context, as *crv1alpha1.ActionSet, aI
 	if err != nil {
 		return err
 	}
-	phases, err := kanister.GetPhases(*bp, action.Name, *tp)
+	phases, err := kanister.GetPhases(*bp, action.Name, action.Version, *tp)
 	if err != nil {
 		return err
 	}

pkg/controller/controller_test.go

@@ -23,11 +23,12 @@ import (
 	"github.com/pkg/errors"
 	. "gopkg.in/check.v1"
 	appsv1 "k8s.io/api/apps/v1"
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/tools/record"
 
+	kanister "github.com/kanisterio/kanister/pkg"
 	crv1alpha1 "github.com/kanisterio/kanister/pkg/apis/cr/v1alpha1"
 	"github.com/kanisterio/kanister/pkg/client/clientset/versioned/scheme"
 	crclientv1alpha1 "github.com/kanisterio/kanister/pkg/client/clientset/versioned/typed/cr/v1alpha1"
@@ -268,42 +269,72 @@ func (s *ControllerSuite) TestExecActionSet(c *C) {
 			funcNames []string
 			args      [][]string
 			name      string
+			version   string
 		}{
 			{
 				funcNames: []string{testutil.WaitFuncName},
 				name:      "WaitFunc",
+				version:   kanister.DefaultVersion,
 			},
 			{
 				funcNames: []string{testutil.WaitFuncName, testutil.WaitFuncName},
 				name:      "WaitWait",
+				version:   kanister.DefaultVersion,
 			},
 			{
 				funcNames: []string{testutil.FailFuncName},
 				name:      "FailFunc",
+				version:   kanister.DefaultVersion,
 			},
 			{
 				funcNames: []string{testutil.WaitFuncName, testutil.FailFuncName},
 				name:      "WaitFail",
+				version:   kanister.DefaultVersion,
 			},
 			{
 				funcNames: []string{testutil.FailFuncName, testutil.WaitFuncName},
 				name:      "FailWait",
+				version:   kanister.DefaultVersion,
 			},
 			{
 				funcNames: []string{testutil.ArgFuncName},
 				name:      "ArgFunc",
+				version:   kanister.DefaultVersion,
 			},
 			{
 				funcNames: []string{testutil.ArgFuncName, testutil.FailFuncName},
 				name:      "ArgFail",
+				version:   kanister.DefaultVersion,
 			},
 			{
 				funcNames: []string{testutil.OutputFuncName},
 				name:      "OutputFunc",
+				version:   kanister.DefaultVersion,
 			},
 			{
 				funcNames: []string{testutil.CancelFuncName},
 				name:      "CancelFunc",
+				version:   kanister.DefaultVersion,
+			},
+			{
+				funcNames: []string{testutil.ArgFuncName},
+				name:      "ArgFuncVersion",
+				version:   testutil.TestVersion,
+			},
+			{
+				funcNames: []string{testutil.ArgFuncName},
+				name:      "ArgFuncVersionFallback",
+				version:   "v1.2.3",
+			},
+			{
+				funcNames: []string{testutil.ArgFuncName},
+				name:      "ArgFuncNoActionSetVersion",
+				version:   "",
+			},
+			{
+				funcNames: []string{testutil.VersionMismatchFuncName},
+				name:      "VersionMismatchFunc",
+				version:   "v1.2.3",
 			},
 		} {
 			var err error
@@ -324,7 +355,7 @@ func (s *ControllerSuite) TestExecActionSet(c *C) {
 			}
 
 			// Add an actionset that references that blueprint.
-			as := testutil.NewTestActionSet(s.namespace, bp.GetName(), pok, n, s.namespace)
+			as := testutil.NewTestActionSet(s.namespace, bp.GetName(), pok, n, s.namespace, tc.version)
 			as = testutil.ActionSetWithConfigMap(as, s.confimap.GetName())
 			as, err = s.crCli.ActionSets(s.namespace).Create(as)
 			c.Assert(err, IsNil, Commentf("Failed case: %s", tc.name))
@@ -352,6 +383,9 @@ func (s *ControllerSuite) TestExecActionSet(c *C) {
 					c.Assert(err, IsNil)
 					c.Assert(testutil.CancelFuncOut().Error(), DeepEquals, "context canceled")
 					cancel = true
+				case testutil.VersionMismatchFuncName:
+					final = crv1alpha1.StateFailed
+					c.Assert(err, IsNil)
 				}
 			}
 
@@ -442,7 +476,7 @@ func (s *ControllerSuite) TestPhaseOutputAsArtifact(c *C) {
 	c.Assert(err, IsNil)
 
 	// Add an actionset that references that blueprint.
-	as := testutil.NewTestActionSet(s.namespace, bp.GetName(), "Deployment", s.deployment.GetName(), s.namespace)
+	as := testutil.NewTestActionSet(s.namespace, bp.GetName(), "Deployment", s.deployment.GetName(), s.namespace, kanister.DefaultVersion)
 	as = testutil.ActionSetWithConfigMap(as, s.confimap.GetName())
 	as, err = s.crCli.ActionSets(s.namespace).Create(as)
 	c.Assert(err, IsNil)
@@ -472,7 +506,7 @@ func (s *ControllerSuite) TestRenderArtifactsFailure(c *C) {
 	c.Assert(err, IsNil)
 
 	// Add an actionset that references that blueprint.
-	as := testutil.NewTestActionSet(s.namespace, bp.GetName(), "Deployment", s.deployment.GetName(), s.namespace)
+	as := testutil.NewTestActionSet(s.namespace, bp.GetName(), "Deployment", s.deployment.GetName(), s.namespace, kanister.DefaultVersion)
 	as = testutil.ActionSetWithConfigMap(as, s.confimap.GetName())
 	as, err = s.crCli.ActionSets(s.namespace).Create(as)
 	c.Assert(err, IsNil)

pkg/function/data_test.go

@@ -532,7 +532,7 @@ func (s *DataSuite) TestCopyData(c *C) {
 }
 
 func runAction(c *C, bp crv1alpha1.Blueprint, action string, tp *param.TemplateParams) map[string]interface{} {
-	phases, err := kanister.GetPhases(bp, action, *tp)
+	phases, err := kanister.GetPhases(bp, action, kanister.DefaultVersion, *tp)
 	c.Assert(err, IsNil)
 	out := make(map[string]interface{})
 	for _, p := range phases {

pkg/function/e2e_volume_snapshot_test.go

@@ -311,7 +311,7 @@ func (s *VolumeSnapshotTestSuite) TestVolumeSnapshot(c *C) {
 	actions := []string{"backup", "restore", "delete"}
 	bp := newVolumeSnapshotBlueprint()
 	for _, action := range actions {
-		phases, err := kanister.GetPhases(*bp, action, *s.tp)
+		phases, err := kanister.GetPhases(*bp, action, kanister.DefaultVersion, *s.tp)
 		c.Assert(err, IsNil)
 		for _, p := range phases {
 			c.Assert(param.InitPhaseParams(ctx, s.cli, s.tp, p.Name(), p.Objects()), IsNil)

pkg/function/kube_exec_all_test.go

@@ -19,7 +19,7 @@ import (
 	"fmt"
 
 	. "gopkg.in/check.v1"
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/dynamic/fake"
 	"k8s.io/client-go/kubernetes"
@@ -129,7 +129,7 @@ func (s *KubeExecAllTest) TestKubeExecAllDeployment(c *C) {
 
 	action := "echo"
 	bp := newExecAllBlueprint(kind)
-	phases, err := kanister.GetPhases(*bp, action, *tp)
+	phases, err := kanister.GetPhases(*bp, action, kanister.DefaultVersion, *tp)
 	c.Assert(err, IsNil)
 	for _, p := range phases {
 		_, err = p.Exec(ctx, *bp, action, *tp)
@@ -163,7 +163,7 @@ func (s *KubeExecAllTest) TestKubeExecAllStatefulSet(c *C) {
 
 	action := "echo"
 	bp := newExecAllBlueprint(kind)
-	phases, err := kanister.GetPhases(*bp, action, *tp)
+	phases, err := kanister.GetPhases(*bp, action, kanister.DefaultVersion, *tp)
 	c.Assert(err, IsNil)
 	for _, p := range phases {
 		_, err = p.Exec(ctx, *bp, action, *tp)

pkg/function/kube_exec_test.go

@@ -158,7 +158,7 @@ func (s *KubeExecTest) TestKubeExec(c *C) {
 
 	action := "echo"
 	bp := newKubeExecBlueprint()
-	phases, err := kanister.GetPhases(*bp, action, *tp)
+	phases, err := kanister.GetPhases(*bp, action, kanister.DefaultVersion, *tp)
 	c.Assert(err, IsNil)
 	for _, p := range phases {
 		_, err = p.Exec(context.Background(), *bp, action, *tp)

pkg/function/kube_task_test.go

@@ -20,7 +20,7 @@ import (
 	"time"
 
 	. "gopkg.in/check.v1"
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	sp "k8s.io/apimachinery/pkg/util/strategicpatch"
 	"k8s.io/client-go/kubernetes"
@@ -153,7 +153,7 @@ func (s *KubeTaskSuite) TestKubeTask(c *C) {
 		},
 	} {
 
-		phases, err := kanister.GetPhases(*tc.bp, action, tp)
+		phases, err := kanister.GetPhases(*tc.bp, action, kanister.DefaultVersion, tp)
 		c.Assert(err, IsNil)
 		c.Assert(phases, HasLen, len(tc.outs))
 		for i, p := range phases {

pkg/function/prepare_data_test.go

@@ -19,7 +19,7 @@ import (
 	"fmt"
 
 	. "gopkg.in/check.v1"
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
 
@@ -144,7 +144,7 @@ func (s *PrepareDataSuite) TestPrepareData(c *C) {
 		}
 		action := "test"
 		bp := newPrepareDataBlueprint(kind, createdPVC.Name)
-		phases, err := kanister.GetPhases(*bp, action, tp)
+		phases, err := kanister.GetPhases(*bp, action, kanister.DefaultVersion, tp)
 		c.Assert(err, IsNil)
 		for _, p := range phases {
 			_, err = p.Exec(ctx, *bp, action, tp)

pkg/function/scale_test.go

@@ -19,7 +19,7 @@ import (
 	"fmt"
 
 	. "gopkg.in/check.v1"
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/dynamic/fake"
 	"k8s.io/client-go/kubernetes"
@@ -159,7 +159,7 @@ func (s *ScaleSuite) TestScaleDeployment(c *C) {
 		tp, err := param.New(ctx, s.cli, fake.NewSimpleDynamicClient(k8sscheme.Scheme, d), s.crCli, as)
 		c.Assert(err, IsNil)
 		bp := newScaleBlueprint(kind)
-		phases, err := kanister.GetPhases(*bp, action, *tp)
+		phases, err := kanister.GetPhases(*bp, action, kanister.DefaultVersion, *tp)
 		c.Assert(err, IsNil)
 		for _, p := range phases {
 			_, err = p.Exec(context.Background(), *bp, action, *tp)
@@ -208,7 +208,7 @@ func (s *ScaleSuite) TestScaleStatefulSet(c *C) {
 		tp, err := param.New(ctx, s.cli, fake.NewSimpleDynamicClient(k8sscheme.Scheme, ss), s.crCli, as)
 		c.Assert(err, IsNil)
 		bp := newScaleBlueprint(kind)
-		phases, err := kanister.GetPhases(*bp, action, *tp)
+		phases, err := kanister.GetPhases(*bp, action, kanister.DefaultVersion, *tp)
 		c.Assert(err, IsNil)
 		for _, p := range phases {
 			_, err = p.Exec(context.Background(), *bp, action, *tp)

pkg/kanister.go

@@ -18,14 +18,19 @@ import (
 	"context"
 	"sync"
 
+	"github.com/Masterminds/semver"
 	"github.com/pkg/errors"
 
 	"github.com/kanisterio/kanister/pkg/param"
 )
 
+const (
+	DefaultVersion = "v0.0.0"
+)
+
 var (
 	funcMu sync.RWMutex
-	funcs  = make(map[string]Func)
+	funcs  = make(map[string]map[semver.Version]Func)
 )
 
 // Func allows custom actions to be executed.
@@ -35,16 +40,38 @@ type Func interface {
 	Exec(context.Context, param.TemplateParams, map[string]interface{}) (map[string]interface{}, error)
 }
 
-// Register allows Funcs to be references by User Defined YAMLs
+// Register allows Funcs to be referenced by User Defined YAMLs
 func Register(f Func) error {
+	version := *semver.MustParse(DefaultVersion)
 	funcMu.Lock()
 	defer funcMu.Unlock()
 	if f == nil {
 		return errors.Errorf("kanister: Cannot register nil function")
 	}
-	if _, dup := funcs[f.Name()]; dup {
-		panic("kanister: Register called twice for function " + f.Name())
+	if _, ok := funcs[f.Name()][version]; ok {
+		panic("kanister: Register called twice for function " + f.Name() + " with version " + DefaultVersion)
+	}
+	if _, ok := funcs[f.Name()]; !ok {
+		funcs[f.Name()] = make(map[semver.Version]Func)
+	}
+	funcs[f.Name()][version] = f
+	return nil
+}
+
+// RegisterVersion allows Kanister Functions to be registered with the given version
+func RegisterVersion(f Func, v string) error {
+	version := *semver.MustParse(v)
+	funcMu.Lock()
+	defer funcMu.Unlock()
+	if f == nil {
+		return errors.Errorf("kanister: Cannot register nil function")
+	}
+	if _, ok := funcs[f.Name()][version]; ok {
+		panic("kanister: Register called twice for function " + f.Name() + " with version " + v)
+	}
+	if _, ok := funcs[f.Name()]; !ok {
+		funcs[f.Name()] = make(map[semver.Version]Func)
 	}
-	funcs[f.Name()] = f
+	funcs[f.Name()][version] = f
 	return nil
 }