Ability to query older versions of a vmspec

I tried to come up with a proper solution to this, but all of them had
flaws.

== Options I found and explored their possibilities

1. Add a new version argument to the Get function.

That's just ugly as hell. I like the Options pattern. Much easier to
update without breaking 300 calls in the codebase.

2. Add a new function on the Repo.

It seems odd and I think it's unnecessary because Get can handle it.

3. Create a function only on the Containerd repo implementation.

That would require checks and casting everywhere we want to use it.

== Conclusion

I picked options 1, because it causes less pain not and long term.
It does not matter what content store we are using, it HAS to be able
to manage versions somehow, even if it's an external service, the
Repository implementation has to handle versions, without versions
we are are playing with a bag of venomous snakes without any kind of
antidote, maybe fun, but not safe.

Related to liquidmetal-dev#66

core/application/app_test.go

@@ -41,12 +41,11 @@ func TestApp_CreateMicroVM(t *testing.T) {
 
 				rm.Get(
 					gomock.AssignableToTypeOf(context.Background()),
-					gomock.Eq("id1234"),
-					gomock.Eq(defaults.MicroVMNamespace),
-				).Return(
-					nil,
-					nil,
-				)
+					gomock.Eq(ports.RepositoryGetOptions{
+						Name:      "id1234",
+						Namespace: defaults.MicroVMNamespace,
+					}),
+				).Return(nil, nil)
 
 				expectedCreatedSpec := createTestSpec("id1234", defaults.MicroVMNamespace)
 				expectedCreatedSpec.Spec.CreatedAt = frozenTime().Unix()
@@ -77,8 +76,10 @@ func TestApp_CreateMicroVM(t *testing.T) {
 			expect: func(rm *mock.MockMicroVMRepositoryMockRecorder, em *mock.MockEventServiceMockRecorder, im *mock.MockIDServiceMockRecorder, pm *mock.MockMicroVMServiceMockRecorder) {
 				rm.Get(
 					gomock.AssignableToTypeOf(context.Background()),
-					gomock.Eq("id1234"),
-					gomock.Eq("default"),
+					gomock.Eq(ports.RepositoryGetOptions{
+						Name:      "id1234",
+						Namespace: "default",
+					}),
 				).Return(
 					nil,
 					nil,
@@ -113,8 +114,10 @@ func TestApp_CreateMicroVM(t *testing.T) {
 			expect: func(rm *mock.MockMicroVMRepositoryMockRecorder, em *mock.MockEventServiceMockRecorder, im *mock.MockIDServiceMockRecorder, pm *mock.MockMicroVMServiceMockRecorder) {
 				rm.Get(
 					gomock.AssignableToTypeOf(context.Background()),
-					gomock.Eq("id1234"),
-					gomock.Eq("default"),
+					gomock.Eq(ports.RepositoryGetOptions{
+						Name:      "id1234",
+						Namespace: "default",
+					}),
 				).Return(
 					createTestSpec("id1234", "default"),
 					nil,
@@ -192,8 +195,10 @@ func TestApp_UpdateMicroVM(t *testing.T) {
 			expect: func(rm *mock.MockMicroVMRepositoryMockRecorder, em *mock.MockEventServiceMockRecorder, im *mock.MockIDServiceMockRecorder, pm *mock.MockMicroVMServiceMockRecorder) {
 				rm.Get(
 					gomock.AssignableToTypeOf(context.Background()),
-					gomock.Eq("id1234"),
-					gomock.Eq("default"),
+					gomock.Eq(ports.RepositoryGetOptions{
+						Name:      "id1234",
+						Namespace: "default",
+					}),
 				).Return(
 					createTestSpec("id1234", "default"),
 					nil,
@@ -288,8 +293,10 @@ func TestApp_DeleteMicroVM(t *testing.T) {
 			expect: func(rm *mock.MockMicroVMRepositoryMockRecorder, em *mock.MockEventServiceMockRecorder, im *mock.MockIDServiceMockRecorder, pm *mock.MockMicroVMServiceMockRecorder) {
 				rm.Get(
 					gomock.AssignableToTypeOf(context.Background()),
-					gomock.Eq("id1234"),
-					gomock.Eq("default"),
+					gomock.Eq(ports.RepositoryGetOptions{
+						Name:      "id1234",
+						Namespace: "default",
+					}),
 				).Return(
 					createTestSpec("id1234", "default"),
 					nil,
@@ -324,8 +331,10 @@ func TestApp_DeleteMicroVM(t *testing.T) {
 			expect: func(rm *mock.MockMicroVMRepositoryMockRecorder, em *mock.MockEventServiceMockRecorder, im *mock.MockIDServiceMockRecorder, pm *mock.MockMicroVMServiceMockRecorder) {
 				rm.Get(
 					gomock.AssignableToTypeOf(context.Background()),
-					gomock.Eq("id1234"),
-					gomock.Eq("default"),
+					gomock.Eq(ports.RepositoryGetOptions{
+						Name:      "id1234",
+						Namespace: "default",
+					}),
 				).Return(
 					nil,
 					nil,

core/application/commands.go

@@ -7,6 +7,7 @@ import (
 	"github.com/weaveworks/flintlock/api/events"
 	coreerrs "github.com/weaveworks/flintlock/core/errors"
 	"github.com/weaveworks/flintlock/core/models"
+	"github.com/weaveworks/flintlock/core/ports"
 	"github.com/weaveworks/flintlock/pkg/defaults"
 	"github.com/weaveworks/flintlock/pkg/log"
 )
@@ -31,12 +32,16 @@ func (a *app) CreateMicroVM(ctx context.Context, mvm *models.MicroVM) (*models.M
 		mvm.ID = *vmid
 	}
 
-	foundMvm, err := a.ports.Repo.Get(ctx, mvm.ID.Name(), mvm.ID.Namespace())
+	foundMvm, err := a.ports.Repo.Get(ctx, ports.RepositoryGetOptions{
+		Name:      mvm.ID.Name(),
+		Namespace: mvm.ID.Namespace(),
+	})
 	if err != nil {
 		if !coreerrs.IsSpecNotFound(err) {
 			return nil, fmt.Errorf("checking to see if spec exists: %w", err)
 		}
 	}
+
 	if foundMvm != nil {
 		return nil, specAlreadyExistsError{
 			name:      mvm.ID.Name(),
@@ -76,10 +81,14 @@ func (a *app) UpdateMicroVM(ctx context.Context, mvm *models.MicroVM) (*models.M
 		return nil, coreerrs.ErrVMIDRequired
 	}
 
-	foundMvm, err := a.ports.Repo.Get(ctx, mvm.ID.Name(), mvm.ID.Namespace())
+	foundMvm, err := a.ports.Repo.Get(ctx, ports.RepositoryGetOptions{
+		Name:      mvm.ID.Name(),
+		Namespace: mvm.ID.Namespace(),
+	})
 	if err != nil {
 		return nil, fmt.Errorf("checking to see if spec exists: %w", err)
 	}
+
 	if foundMvm == nil {
 		return nil, specNotFoundError{
 			name:      mvm.ID.Name(),
@@ -116,10 +125,14 @@ func (a *app) DeleteMicroVM(ctx context.Context, id, namespace string) error {
 		return errIDRequired
 	}
 
-	foundMvm, err := a.ports.Repo.Get(ctx, id, namespace)
+	foundMvm, err := a.ports.Repo.Get(ctx, ports.RepositoryGetOptions{
+		Name:      id,
+		Namespace: namespace,
+	})
 	if err != nil {
 		return fmt.Errorf("checking to see if spec exists: %w", err)
 	}
+
 	if foundMvm == nil {
 		return specNotFoundError{
 			name:      id,

core/application/reconcile.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/weaveworks/flintlock/core/models"
 	"github.com/weaveworks/flintlock/core/plans"
+	"github.com/weaveworks/flintlock/core/ports"
 	portsctx "github.com/weaveworks/flintlock/core/ports/context"
 	"github.com/weaveworks/flintlock/pkg/log"
 	"github.com/weaveworks/flintlock/pkg/planner"
@@ -17,7 +18,10 @@ func (a *app) ReconcileMicroVM(ctx context.Context, id, namespace string) error
 	logger := log.GetLogger(ctx).WithField("action", "reconcile")
 
 	logger.Debugf("Getting spec for %s/%s", namespace, id)
-	spec, err := a.ports.Repo.Get(ctx, id, namespace)
+	spec, err := a.ports.Repo.Get(ctx, ports.RepositoryGetOptions{
+		Name:      id,
+		Namespace: namespace,
+	})
 	if err != nil {
 		return fmt.Errorf("getting microvm spec for reconcile: %w", err)
 	}

core/errors/errors.go

@@ -89,21 +89,27 @@ func (e NetworkInterfaceStatusMissingError) Error() string {
 	return fmt.Sprintf("status for network interface %s is not found", e.guestIface)
 }
 
-func NewSpecNotFound(name, namespace string) error {
+func NewSpecNotFound(name, namespace, version string) error {
 	return specNotFoundError{
 		name:      name,
 		namespace: namespace,
+		version:   version,
 	}
 }
 
 type specNotFoundError struct {
 	name      string
 	namespace string
+	version   string
 }
 
 // Error returns the error message.
 func (e specNotFoundError) Error() string {
-	return fmt.Sprintf("microvm spec %s/%s not found", e.namespace, e.name)
+	if e.version == "" {
+		return fmt.Sprintf("microvm spec %s/%s not found", e.namespace, e.name)
+	}
+
+	return fmt.Sprintf("microvm spec %s/%s not found with version %s", e.namespace, e.name, e.version)
 }
 
 // IsSpecNotFound tests an error to see if its a spec not found error.

core/ports/repositories.go

@@ -6,14 +6,20 @@ import (
 	"github.com/weaveworks/flintlock/core/models"
 )
 
+type RepositoryGetOptions struct {
+	Name      string
+	Namespace string
+	Version   string
+}
+
 // MicroVMRepository is the port definition for a microvm repository.
 type MicroVMRepository interface {
 	// Save will save the supplied microvm spec.
 	Save(ctx context.Context, microvm *models.MicroVM) (*models.MicroVM, error)
 	// Delete will delete the supplied microvm.
 	Delete(ctx context.Context, microvm *models.MicroVM) error
 	// Get will get the microvm spec with the given name/namespace.
-	Get(ctx context.Context, name, namespace string) (*models.MicroVM, error)
+	Get(ctx context.Context, options RepositoryGetOptions) (*models.MicroVM, error)
 	// GetAll will get a list of microvm details. If namespace is an empty string all
 	// details of microvms will be returned.
 	GetAll(ctx context.Context, namespace string) ([]*models.MicroVM, error)

go.mod

@@ -82,6 +82,7 @@ require (
 	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/golang/snappy v0.0.3 // indirect
 	github.com/google/gofuzz v1.1.0 // indirect
+	github.com/google/subcommands v1.0.1 // indirect
 	github.com/google/uuid v1.3.0 // indirect
 	github.com/googleapis/gnostic v0.4.1 // indirect
 	github.com/gruntwork-io/go-commons v0.8.0 // indirect
@@ -130,13 +131,16 @@ require (
 	go.mongodb.org/mongo-driver v1.3.4 // indirect
 	go.opencensus.io v0.23.0 // indirect
 	golang.org/x/crypto v0.0.0-20210817164053-32db794688a5 // indirect
+	golang.org/x/mod v0.4.2 // indirect
 	golang.org/x/net v0.0.0-20210614182718-04defd469f4e // indirect
 	golang.org/x/oauth2 v0.0.0-20210819190943-2bc19b11175f // indirect
 	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c // indirect
 	golang.org/x/sys v0.0.0-20210823070655-63515b42dcdf // indirect
 	golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1 // indirect
 	golang.org/x/text v0.3.6 // indirect
 	golang.org/x/time v0.0.0-20200630173020-3af7569d3a1e // indirect
+	golang.org/x/tools v0.1.5 // indirect
+	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
 	google.golang.org/appengine v1.6.7 // indirect
 	google.golang.org/genproto v0.0.0-20211021150943-2b146023228c // indirect
 	gopkg.in/inf.v0 v0.9.1 // indirect

go.sum

@@ -572,6 +572,7 @@ github.com/google/pprof v0.0.0-20210601050228-01bbb1931b22/go.mod h1:kpwsk12EmLe
 github.com/google/pprof v0.0.0-20210609004039-a478d1d731e9/go.mod h1:kpwsk12EmLew5upagYY7GY0pfYCcupk39gWOCRROcvE=
 github.com/google/pprof v0.0.0-20210720184732-4bb14d4b1be1/go.mod h1:kpwsk12EmLew5upagYY7GY0pfYCcupk39gWOCRROcvE=
 github.com/google/renameio v0.1.0/go.mod h1:KWCgfxg9yswjAJkECMjeO8J8rahYeXnNhOm40UhjYkI=
+github.com/google/subcommands v1.0.1 h1:/eqq+otEXm5vhfBrbREPCSVQbvofip6kIz+mX5TUH7k=
 github.com/google/subcommands v1.0.1/go.mod h1:ZjhPrFU+Olkh9WazFPsl27BQ4UPiG37m3yTrtFlrHVk=
 github.com/google/uuid v1.0.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/google/uuid v1.1.1/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
@@ -1119,6 +1120,7 @@ golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.1/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
+golang.org/x/mod v0.4.2 h1:Gz96sIWK3OalVv/I/qNygP42zyoKp3xptRVCWRFEBvo=
 golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180811021610-c39426892332/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
@@ -1394,6 +1396,7 @@ golang.org/x/tools v0.1.1/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/tools v0.1.2/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/tools v0.1.3/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/tools v0.1.4/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
+golang.org/x/tools v0.1.5 h1:ouewzE6p+/VEB31YYnTbEJdi8pFqKp4P4n85vwo3DHA=
 golang.org/x/tools v0.1.5/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=