Allow opening S3 repo at a specific point-in-time

Thread the PointInTime argument through corso to kopia so that S3 repos
can be opened at a specific point if they're using versioning and object
locking.

src/internal/kopia/conn.go

@@ -71,7 +71,7 @@ func NewConn(s storage.Storage) *conn {
 }
 
 func (w *conn) Initialize(ctx context.Context, opts repository.Options) error {
-	bst, err := blobStoreByProvider(ctx, w.storage)
+	bst, err := blobStoreByProvider(ctx, opts, w.storage)
 	if err != nil {
 		return clues.Wrap(err, "initializing storage")
 	}
@@ -111,7 +111,7 @@ func (w *conn) Initialize(ctx context.Context, opts repository.Options) error {
 }
 
 func (w *conn) Connect(ctx context.Context, opts repository.Options) error {
-	bst, err := blobStoreByProvider(ctx, w.storage)
+	bst, err := blobStoreByProvider(ctx, opts, w.storage)
 	if err != nil {
 		return clues.Wrap(err, "initializing storage")
 	}
@@ -174,10 +174,14 @@ func (w *conn) commonConnect(
 	return nil
 }
 
-func blobStoreByProvider(ctx context.Context, s storage.Storage) (blob.Storage, error) {
+func blobStoreByProvider(
+	ctx context.Context,
+	opts repository.Options,
+	s storage.Storage,
+) (blob.Storage, error) {
 	switch s.Provider {
 	case storage.ProviderS3:
-		return s3BlobStorage(ctx, s)
+		return s3BlobStorage(ctx, opts, s)
 	default:
 		return nil, clues.New("storage provider details are required").WithClues(ctx)
 	}

src/internal/kopia/s3.go

@@ -7,6 +7,7 @@ import (
 	"github.com/kopia/kopia/repo/blob"
 	"github.com/kopia/kopia/repo/blob/s3"
 
+	"github.com/alcionai/corso/src/pkg/control/repository"
 	"github.com/alcionai/corso/src/pkg/storage"
 )
 
@@ -14,7 +15,11 @@ const (
 	defaultS3Endpoint = "s3.amazonaws.com" // matches kopia's default value
 )
 
-func s3BlobStorage(ctx context.Context, s storage.Storage) (blob.Storage, error) {
+func s3BlobStorage(
+	ctx context.Context,
+	repoOpts repository.Options,
+	s storage.Storage,
+) (blob.Storage, error) {
 	cfg, err := s.S3Config()
 	if err != nil {
 		return nil, clues.Stack(err).WithClues(ctx)
@@ -36,6 +41,7 @@ func s3BlobStorage(ctx context.Context, s storage.Storage) (blob.Storage, error)
 		RoleARN:             s.Role,
 		RoleDuration:        s.SessionDuration,
 		TLSHandshakeTimeout: 60,
+		PointInTime:         repoOpts.ViewTimestamp,
 	}
 
 	store, err := s3.New(ctx, &opts, false)

src/pkg/control/repository/repo.go

@@ -1,9 +1,16 @@
 package repository
 
+import (
+	"time"
+)
+
 // Repo represents options that are specific to the repo storing backed up data.
 type Options struct {
 	User string `json:"user"`
 	Host string `json:"host"`
+	// ViewTimestamp is the time at which the repo should be opened at if
+	// immutable backups are being used. If nil then the current time is used.
+	ViewTimestamp *time.Time `json:"viewTimestamp"`
 }
 
 type Maintenance struct {