adds a subtree migration iface to kopia

Introdudces the user pn to id migration. Since
onedrive doesn't enumerate folders on backup,
we have to force the migration by introducing a
subtree migrator in kopia.

src/internal/data/data_collection.go

@@ -132,7 +132,7 @@ func StateOf(prev, curr path.Path) CollectionState {
 		return NewState
 	}
 
-	if curr.Folder(false) != prev.Folder(false) {
+	if curr.String() != prev.String() {
 		return MovedState
 	}
 

src/internal/kopia/migrations.go

@@ -0,0 +1,40 @@
+package kopia
+
+import (
+	"strings"
+
+	"github.com/alcionai/corso/src/pkg/path"
+)
+
+type SubtreeMigrator interface {
+	// GetNewSubtree potentially transforms a given subtree (repo tree prefix
+	// corresponding to a kopia Reason (eg: resource owner, service, category)
+	// into a new subtree when merging items from the base tree.
+	GetNewSubtree(oldSubtree *path.Builder) *path.Builder
+}
+
+type subtreeOwnerMigrator struct {
+	new, old string
+}
+
+// migrates any subtree with a matching old owner onto the new owner
+func (om subtreeOwnerMigrator) GetNewSubtree(old *path.Builder) *path.Builder {
+	if old == nil {
+		return nil
+	}
+
+	elems := old.Elements()
+	if len(elems) < 4 {
+		return old
+	}
+
+	if strings.EqualFold(elems[2], om.old) {
+		elems[2] = om.new
+	}
+
+	return path.Builder{}.Append(elems...)
+}
+
+func NewSubtreeOwnerMigration(new, old string) *subtreeOwnerMigrator {
+	return &subtreeOwnerMigrator{new, old}
+}

src/internal/kopia/migrations_test.go

@@ -0,0 +1,62 @@
+package kopia
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/suite"
+
+	"github.com/alcionai/corso/src/internal/tester"
+	"github.com/alcionai/corso/src/pkg/path"
+)
+
+type MigrationsUnitSuite struct {
+	tester.Suite
+}
+
+func TestMigrationsUnitSuite(t *testing.T) {
+	suite.Run(t, &MigrationsUnitSuite{Suite: tester.NewUnitSuite(t)})
+}
+
+func (suite *MigrationsUnitSuite) TestSubtreeOwnerMigration_GetNewSubtree() {
+	table := []struct {
+		name   string
+		input  *path.Builder
+		expect *path.Builder
+	}{
+		{
+			name: "nil builder",
+		},
+		{
+			name:   "builder too small",
+			input:  path.Builder{}.Append("foo"),
+			expect: path.Builder{}.Append("foo"),
+		},
+		{
+			name:   "non-matching owner",
+			input:  path.Builder{}.Append("foo", "bar", "ownerronwo", "baz"),
+			expect: path.Builder{}.Append("foo", "bar", "ownerronwo", "baz"),
+		},
+		{
+			name:   "migrated",
+			input:  path.Builder{}.Append("foo", "bar", "owner", "baz"),
+			expect: path.Builder{}.Append("foo", "bar", "migrated", "baz"),
+		},
+	}
+	for _, test := range table {
+		suite.Run(test.name, func() {
+			var (
+				t      = suite.T()
+				stm    = NewSubtreeOwnerMigration("migrated", "owner")
+				result = stm.GetNewSubtree(test.input)
+			)
+
+			if result == nil {
+				assert.Nil(t, test.expect)
+				return
+			}
+
+			assert.Equal(t, test.expect.String(), result.String())
+		})
+	}
+}

src/internal/kopia/path_encoder.go

@@ -20,6 +20,22 @@ func encodeElements(elements ...string) []string {
 	return encoded
 }
 
+func decodeElements(elements ...string) []string {
+	decoded := make([]string, 0, len(elements))
+
+	for _, e := range elements {
+		bs, err := encoder.DecodeString(e)
+		if err != nil {
+			decoded = append(decoded, "error decoding: "+e)
+			continue
+		}
+
+		decoded = append(decoded, string(bs))
+	}
+
+	return decoded
+}
+
 // encodeAsPath takes a set of elements and returns the concatenated elements as
 // if they were a path. The elements are joined with the separator in the golang
 // path package.

src/internal/kopia/upload.go

@@ -138,6 +138,9 @@ type corsoProgress struct {
 	// toMerge represents items that we don't have in-memory item info for. The
 	// item info for these items should be sourced from a base snapshot later on.
 	toMerge *mergeDetails
+	// the SubtreeMigrator can be optionally poplated to force a subtree migration
+	// when merging files from the a prior base.
+	stm        SubtreeMigrator
 	mu         sync.RWMutex
 	totalBytes int64
 	errs       *fault.Bus
@@ -890,8 +893,7 @@ func traverseBaseDir(
 			oldDirPath,
 			currentPath,
 			dEntry,
-			roots,
+			roots)
-		)
 	})
 	if err != nil {
 		return clues.Wrap(err, "traversing base directory")
@@ -948,6 +950,7 @@ func inflateBaseTree(
 	snap IncrementalBase,
 	updatedPaths map[string]path.Path,
 	roots map[string]*treeMap,
+	stm SubtreeMigrator,
 ) error {
 	// Only complete snapshots should be used to source base information.
 	// Snapshots for checkpoints will rely on kopia-assisted dedupe to efficiently
@@ -991,6 +994,11 @@ func inflateBaseTree(
 			return clues.Wrap(err, "subtree root is not directory").WithClues(ictx)
 		}
 
+		migratedPath := subtreePath
+		if stm != nil {
+			migratedPath = stm.GetNewSubtree(subtreePath)
+		}
+
 		// We're assuming here that the prefix for the path has not changed (i.e.
 		// all of tenant, service, resource owner, and category are the same in the
 		// old snapshot (snap) and the snapshot we're currently trying to make.
@@ -999,7 +1007,7 @@ func inflateBaseTree(
 			0,
 			updatedPaths,
 			subtreePath.Dir(),
-			subtreePath.Dir(),
+			migratedPath.Dir(),
 			subtreeDir,
 			roots,
 		); err != nil {
@@ -1050,7 +1058,8 @@ func inflateDirTree(
 	}
 
 	for _, snap := range baseSnaps {
-		if err = inflateBaseTree(ctx, loader, snap, updatedPaths, roots); err != nil {
+		err := inflateBaseTree(ctx, loader, snap, updatedPaths, roots, progress.stm)
+		if err != nil {
 			return nil, clues.Wrap(err, "inflating base snapshot tree(s)")
 		}
 	}

src/internal/kopia/upload_test.go

@@ -183,16 +183,16 @@ func expectDirs(
 ) {
 	t.Helper()
 
-	if exactly {
+	ents := make([]string, 0, len(entries))
-		require.Len(t, entries, len(dirs))
-	}
-
-	names := make([]string, 0, len(entries))
 	for _, e := range entries {
-		names = append(names, e.Name())
+		ents = append(ents, e.Name())
 	}
 
-	assert.Subset(t, names, dirs)
+	if exactly {
+		require.Lenf(t, entries, len(dirs), "expected %+v\ngot %+v", decodeElements(dirs...), decodeElements(ents...))
+	}
+
+	assert.Subsetf(t, dirs, ents, "expected %+v\ngot %+v", decodeElements(dirs...), decodeElements(ents...))
 }
 
 func getDirEntriesForEntry(
@@ -2727,3 +2727,248 @@ func (suite *HierarchyBuilderUnitSuite) TestBuildDirectoryTreeSelectsCorrectSubt
 
 	expectTree(t, ctx, expected, dirTree)
 }
+
+type baseMigrator struct {
+	pb *path.Builder
+}
+
+func (bm baseMigrator) GetNewSubtree(_ *path.Builder) *path.Builder {
+	return bm.pb
+}
+
+func (suite *HierarchyBuilderUnitSuite) TestBuildDirectoryTree_migratesBaseSubtree() {
+	tester.LogTimeOfTest(suite.T())
+	t := suite.T()
+
+	ctx, flush := tester.NewContext()
+	defer flush()
+
+	const contactsDir = "contacts"
+
+	var (
+		inboxPath = makePath(
+			suite.T(),
+			[]string{testTenant, service, "owny", category, testInboxID},
+			false)
+
+		inboxFileName1 = testFileName
+		inboxFileName2 = testFileName2
+
+		inboxFileData1   = testFileData
+		inboxFileData1v2 = testFileData5
+		inboxFileData2   = testFileData2
+
+		contactsFileName1 = testFileName3
+		contactsFileData1 = testFileData3
+
+		eventsFileName1 = testFileName5
+		eventsFileData1 = testFileData
+	)
+
+	// Must be a function that returns a new instance each time as StreamingFile
+	// can only return its Reader once.
+	// baseSnapshot with the following layout:
+	// - a-tenant
+	//   - exchange
+	//     - user1
+	//       - email
+	//         - Inbox
+	//           - file1
+	//       - contacts
+	//         - contacts
+	//           - file2
+	getBaseSnapshot1 := func() fs.Entry {
+		return baseWithChildren(
+			[]string{
+				testTenant,
+				service,
+				testUser,
+			},
+			[]fs.Entry{
+				virtualfs.NewStaticDirectory(
+					encodeElements(category)[0],
+					[]fs.Entry{
+						virtualfs.NewStaticDirectory(
+							encodeElements(testInboxID)[0],
+							[]fs.Entry{
+								virtualfs.StreamingFileWithModTimeFromReader(
+									encodeElements(inboxFileName1)[0],
+									time.Time{},
+									io.NopCloser(bytes.NewReader(inboxFileData1)),
+								),
+							},
+						),
+					},
+				),
+				virtualfs.NewStaticDirectory(
+					encodeElements(path.ContactsCategory.String())[0],
+					[]fs.Entry{
+						virtualfs.NewStaticDirectory(
+							encodeElements(contactsDir)[0],
+							[]fs.Entry{
+								virtualfs.StreamingFileWithModTimeFromReader(
+									encodeElements(contactsFileName1)[0],
+									time.Time{},
+									io.NopCloser(bytes.NewReader(contactsFileData1)),
+								),
+							},
+						),
+					},
+				),
+			},
+		)
+	}
+
+	// Must be a function that returns a new instance each time as StreamingFile
+	// can only return its Reader once.
+	// baseSnapshot with the following layout:
+	// - a-tenant
+	//   - exchange
+	//     - user1
+	//       - email
+	//         - Inbox
+	//           - file1 <- has different data version
+	//       - events
+	//         - events
+	//           - file3
+	getBaseSnapshot2 := func() fs.Entry {
+		return baseWithChildren(
+			[]string{
+				testTenant,
+				service,
+				testUser,
+			},
+			[]fs.Entry{
+				virtualfs.NewStaticDirectory(
+					encodeElements(category)[0],
+					[]fs.Entry{
+						virtualfs.NewStaticDirectory(
+							encodeElements(testInboxID)[0],
+							[]fs.Entry{
+								virtualfs.StreamingFileWithModTimeFromReader(
+									encodeElements(inboxFileName1)[0],
+									time.Time{},
+									// Wrap with a backup reader so it gets the version injected.
+									newBackupStreamReader(
+										serializationVersion,
+										io.NopCloser(bytes.NewReader(inboxFileData1v2)),
+									),
+								),
+							},
+						),
+					},
+				),
+				virtualfs.NewStaticDirectory(
+					encodeElements(path.EventsCategory.String())[0],
+					[]fs.Entry{
+						virtualfs.NewStaticDirectory(
+							encodeElements("events")[0],
+							[]fs.Entry{
+								virtualfs.StreamingFileWithModTimeFromReader(
+									encodeElements(eventsFileName1)[0],
+									time.Time{},
+									io.NopCloser(bytes.NewReader(eventsFileData1)),
+								),
+							},
+						),
+					},
+				),
+			},
+		)
+	}
+
+	// Check the following:
+	//   * contacts pulled from base1 unchanged even if no collections reference
+	//     it
+	//   * email pulled from base2
+	//   * new email added
+	//   * events not pulled from base2 as it's not listed as a Reason
+	//
+	// Expected output:
+	// - a-tenant
+	//   - exchange
+	//     - owny <- migrated
+	//       - email
+	//         - Inbox
+	//           - file1 <- version of data from second base
+	//           - file2
+	//       - contacts
+	//         - contacts
+	//           - file2
+	expected := expectedTreeWithChildren(
+		[]string{testTenant, path.ExchangeService.String(), "owny"},
+		[]*expectedNode{
+			{
+				name: category,
+				children: []*expectedNode{
+					{
+						name: testInboxID,
+						children: []*expectedNode{
+							{
+								name:     inboxFileName1,
+								children: []*expectedNode{},
+								data:     inboxFileData1v2,
+							},
+							{
+								name:     inboxFileName2,
+								children: []*expectedNode{},
+								data:     inboxFileData2,
+							},
+						},
+					},
+				},
+			},
+			{
+				name: path.ContactsCategory.String(),
+				children: []*expectedNode{
+					{
+						name: contactsDir,
+						children: []*expectedNode{
+							{
+								name:     contactsFileName1,
+								children: []*expectedNode{},
+							},
+						},
+					},
+				},
+			},
+		},
+	)
+
+	progress := &corsoProgress{
+		pending: map[string]*itemDetails{},
+		toMerge: newMergeDetails(),
+		errs:    fault.New(true),
+		stm:     baseMigrator{path.Builder{}.Append(testTenant, path.ExchangeService.String(), "owny", category)},
+	}
+
+	mc := mockconnector.NewMockExchangeCollection(inboxPath, inboxPath, 1)
+	mc.PrevPath = mc.FullPath()
+	mc.ColState = data.NotMovedState
+	mc.Names[0] = inboxFileName2
+	mc.Data[0] = inboxFileData2
+
+	msw := &mockMultiSnapshotWalker{
+		snaps: map[string]fs.Entry{
+			"id1": getBaseSnapshot1(),
+			"id2": getBaseSnapshot2(),
+		},
+	}
+
+	collections := []data.BackupCollection{mc}
+
+	dirTree, err := inflateDirTree(
+		ctx,
+		msw,
+		[]IncrementalBase{
+			mockIncrementalBase("id1", testTenant, testUser, path.ExchangeService, path.ContactsCategory),
+			mockIncrementalBase("id2", testTenant, testUser, path.ExchangeService, path.EmailCategory),
+		},
+		collections,
+		nil,
+		progress,
+	)
+	require.NoError(t, err, clues.ToCore(err))
+
+	expectTree(t, ctx, expected, dirTree)
+}

src/internal/kopia/wrapper.go

@@ -137,6 +137,7 @@ func (w Wrapper) ConsumeBackupCollections(
 	globalExcludeSet map[string]map[string]struct{},
 	tags map[string]string,
 	buildTreeWithBase bool,
+	stm SubtreeMigrator,
 	errs *fault.Bus,
 ) (*BackupStats, *details.Builder, DetailsMergeInfoer, error) {
 	if w.c == nil {
@@ -155,6 +156,7 @@ func (w Wrapper) ConsumeBackupCollections(
 		deets:   &details.Builder{},
 		toMerge: newMergeDetails(),
 		errs:    errs,
+		stm:     stm,
 	}
 
 	// When running an incremental backup, we need to pass the prior

src/internal/kopia/wrapper_test.go

@@ -283,6 +283,7 @@ func (suite *KopiaIntegrationSuite) TestBackupCollections() {
 				nil,
 				tags,
 				true,
+				nil,
 				fault.New(true))
 			assert.NoError(t, err, clues.ToCore(err))
 
@@ -430,6 +431,7 @@ func (suite *KopiaIntegrationSuite) TestBackupCollections_NoDetailsForMeta() {
 				nil,
 				tags,
 				true,
+				nil,
 				fault.New(true))
 			assert.NoError(t, err, clues.ToCore(err))
 
@@ -528,6 +530,7 @@ func (suite *KopiaIntegrationSuite) TestRestoreAfterCompressionChange() {
 		nil,
 		tags,
 		true,
+		nil,
 		fault.New(true))
 	require.NoError(t, err, clues.ToCore(err))
 
@@ -647,6 +650,7 @@ func (suite *KopiaIntegrationSuite) TestBackupCollections_ReaderError() {
 		nil,
 		tags,
 		true,
+		nil,
 		fault.New(true))
 	require.Error(t, err, clues.ToCore(err))
 	assert.Equal(t, 0, stats.ErrorCount)
@@ -709,6 +713,7 @@ func (suite *KopiaIntegrationSuite) TestBackupCollectionsHandlesNoCollections()
 				nil,
 				nil,
 				true,
+				nil,
 				fault.New(true))
 			require.NoError(t, err, clues.ToCore(err))
 
@@ -869,6 +874,7 @@ func (suite *KopiaSimpleRepoIntegrationSuite) SetupTest() {
 		nil,
 		tags,
 		false,
+		nil,
 		fault.New(true))
 	require.NoError(t, err, clues.ToCore(err))
 	require.Equal(t, stats.ErrorCount, 0)
@@ -1028,6 +1034,7 @@ func (suite *KopiaSimpleRepoIntegrationSuite) TestBackupExcludeItem() {
 				excluded,
 				tags,
 				true,
+				nil,
 				fault.New(true))
 			require.NoError(t, err, clues.ToCore(err))
 			assert.Equal(t, test.expectedCachedItems, stats.CachedFileCount)

src/internal/operations/backup.go

@@ -230,8 +230,8 @@ func (op *BackupOperation) do(
 	backupID model.StableID,
 ) (*details.Builder, error) {
 	var (
-		reasons         = selectorToReasons(op.Selectors, false)
+		reasons              = selectorToReasons(op.Selectors, op.Selectors.DiscreteOwner)
-		fallbackReasons = makeFallbackReasons(op.Selectors)
+		fallbackReasons, stm = makeFallbackReasons(op.Selectors)
 	)
 
 	logger.Ctx(ctx).With("selectors", op.Selectors).Info("backing up selection")
@@ -274,6 +274,7 @@ func (op *BackupOperation) do(
 		excludes,
 		backupID,
 		op.incremental && canUseMetaData,
+		stm,
 		op.Errors)
 	if err != nil {
 		return nil, clues.Wrap(err, "persisting collection backups")
@@ -300,13 +301,25 @@ func (op *BackupOperation) do(
 	return deets, nil
 }
 
-func makeFallbackReasons(sel selectors.Selector) []kopia.Reason {
+func makeFallbackReasons(sel selectors.Selector) ([]kopia.Reason, kopia.SubtreeMigrator) {
-	if sel.PathService() != path.SharePointService &&
+	if sel.PathService() == path.SharePointService ||
-		sel.DiscreteOwner != sel.DiscreteOwnerName {
+		sel.DiscreteOwner == sel.DiscreteOwnerName {
-		return selectorToReasons(sel, true)
+		return nil, nil
 	}
 
-	return nil
+	var (
+		fbs = selectorToReasons(sel, sel.DiscreteOwnerName)
+		stm kopia.SubtreeMigrator
+	)
+
+	switch sel.PathService() {
+	// only onedrive is required here.  Exchange will naturally get migrated
+	// since all exchange folders are enumerated during backup collection aggregation.
+	case path.OneDriveService:
+		stm = kopia.NewSubtreeOwnerMigration(sel.DiscreteOwner, sel.DiscreteOwnerName)
+	}
+
+	return fbs, stm
 }
 
 // checker to see if conditions are correct for incremental backup behavior such as
@@ -350,7 +363,7 @@ func produceBackupDataCollections(
 // Consumer funcs
 // ---------------------------------------------------------------------------
 
-func selectorToReasons(sel selectors.Selector, useOwnerNameForID bool) []kopia.Reason {
+func selectorToReasons(sel selectors.Selector, owner string) []kopia.Reason {
 	service := sel.PathService()
 	reasons := []kopia.Reason{}
 
@@ -361,11 +374,6 @@ func selectorToReasons(sel selectors.Selector, useOwnerNameForID bool) []kopia.R
 		return nil
 	}
 
-	owner := sel.DiscreteOwner
-	if useOwnerNameForID {
-		owner = sel.DiscreteOwnerName
-	}
-
 	for _, sl := range [][]path.CategoryType{pcs.Includes, pcs.Filters} {
 		for _, cat := range sl {
 			reasons = append(reasons, kopia.Reason{
@@ -410,6 +418,7 @@ func consumeBackupCollections(
 	excludes map[string]map[string]struct{},
 	backupID model.StableID,
 	isIncremental bool,
+	stm kopia.SubtreeMigrator,
 	errs *fault.Bus,
 ) (*kopia.BackupStats, *details.Builder, kopia.DetailsMergeInfoer, error) {
 	complete, closer := observe.MessageWithCompletion(ctx, "Backing up data")
@@ -483,6 +492,7 @@ func consumeBackupCollections(
 		excludes,
 		tags,
 		isIncremental,
+		stm,
 		errs)
 	if err != nil {
 		if kopiaStats == nil {

src/internal/operations/backup_integration_test.go

@@ -31,6 +31,7 @@ import (
 	"github.com/alcionai/corso/src/internal/kopia"
 	"github.com/alcionai/corso/src/internal/model"
 	"github.com/alcionai/corso/src/internal/operations/inject"
+	"github.com/alcionai/corso/src/internal/streamstore"
 	"github.com/alcionai/corso/src/internal/tester"
 	"github.com/alcionai/corso/src/internal/version"
 	"github.com/alcionai/corso/src/pkg/account"
@@ -1599,6 +1600,139 @@ func (suite *BackupOpIntegrationSuite) TestBackup_Run_oneDriveIncrementals() {
 	}
 }
 
+func (suite *BackupOpIntegrationSuite) TestBackup_Run_oneDriveOwnerMigration() {
+	ctx, flush := tester.NewContext()
+	defer flush()
+
+	var (
+		t    = suite.T()
+		acct = tester.NewM365Account(t)
+		ffs  = control.Toggles{}
+		mb   = evmock.NewBus()
+
+		// `now` has to be formatted with SimpleDateTimeOneDrive as
+		// some onedrive cannot have `:` in file/folder names
+		now = common.FormatNow(common.SimpleTimeTesting)
+
+		owners = []string{suite.user}
+
+		categories = map[path.CategoryType][]string{
+			path.FilesCategory: {graph.DeltaURLsFileName, graph.PreviousPathFileName},
+		}
+		container = fmt.Sprintf("%s%d_%s", incrementalsDestContainerPrefix, 1, now)
+		genDests  = []string{container}
+	)
+
+	creds, err := acct.M365Config()
+	require.NoError(t, err, clues.ToCore(err))
+
+	gc, err := connector.NewGraphConnector(
+		ctx,
+		graph.HTTPClient(graph.NoTimeout()),
+		acct,
+		connector.Users,
+		fault.New(true))
+	require.NoError(t, err, clues.ToCore(err))
+
+	driveID := mustGetDefaultDriveID(t, ctx, gc.Service, suite.user)
+
+	fileDBF := func(id, timeStamp, subject, body string) []byte {
+		return []byte(id + subject)
+	}
+
+	// Populate initial test data.
+	for _, destName := range genDests {
+		generateContainerOfItems(
+			t,
+			ctx,
+			gc,
+			path.OneDriveService,
+			acct,
+			path.FilesCategory,
+			selectors.NewOneDriveRestore(owners).Selector,
+			creds.AzureTenantID, suite.user, driveID, destName,
+			2,
+			// Use an old backup version so we don't need metadata files.
+			0,
+			fileDBF)
+	}
+
+	// container3 does not exist yet. It will get created later on
+	// during the tests.
+	containers := []string{container}
+	sel := selectors.NewOneDriveBackup(owners)
+	sel.Include(sel.Folders(containers, selectors.PrefixMatch()))
+
+	bo, _, kw, ms, gc, closer := prepNewTestBackupOp(t, ctx, mb, sel.Selector, ffs)
+	defer closer()
+
+	// ensure the initial owner uses name in both cases
+	sel.SetDiscreteOwnerIDName(suite.user, suite.user)
+	bo.ResourceOwner = sel
+
+	// TODO: ensure this equals the PN
+	require.Equal(t, bo.ResourceOwner.Name(), bo.ResourceOwner.ID(), "historical representation of user")
+
+	// run the initial backup
+	runAndCheckBackup(t, ctx, &bo, mb, false)
+
+	var (
+		incMB = evmock.NewBus()
+		// the incremental backup op should have a proper user ID for the id.
+		incBO = newTestBackupOp(t, ctx, kw, ms, gc, acct, sel.Selector, incMB, ffs, closer)
+	)
+
+	require.NotEqual(
+		t,
+		incBO.ResourceOwner.Name(),
+		incBO.ResourceOwner.ID(),
+		"current representation of user: id should differ from PN")
+
+	err = incBO.Run(ctx)
+	require.NoError(t, err, clues.ToCore(err))
+	checkBackupIsInManifests(t, ctx, kw, &incBO, sel.Selector, suite.user, maps.Keys(categories)...)
+	checkMetadataFilesExist(
+		t,
+		ctx,
+		incBO.Results.BackupID,
+		kw,
+		ms,
+		creds.AzureTenantID,
+		suite.user,
+		path.OneDriveService,
+		categories)
+
+	// 2 on read/writes to account for metadata: 1 delta and 1 path.
+	assert.LessOrEqual(t, 2, incBO.Results.ItemsWritten, "items written")
+	assert.LessOrEqual(t, 2, incBO.Results.ItemsRead, "items read")
+	assert.NoError(t, incBO.Errors.Failure(), "non-recoverable error", clues.ToCore(incBO.Errors.Failure()))
+	assert.Empty(t, incBO.Errors.Recovered(), "recoverable/iteration errors")
+	assert.Equal(t, 1, incMB.TimesCalled[events.BackupStart], "backup-start events")
+	assert.Equal(t, 1, incMB.TimesCalled[events.BackupEnd], "backup-end events")
+	assert.Equal(t,
+		incMB.CalledWith[events.BackupStart][0][events.BackupID],
+		incBO.Results.BackupID, "backupID pre-declaration")
+
+	bid := incBO.Results.BackupID
+	bup := &backup.Backup{}
+
+	err = ms.Get(ctx, model.BackupSchema, bid, bup)
+	require.NoError(t, err, clues.ToCore(err))
+
+	var (
+		ssid  = bup.StreamStoreID
+		deets details.Details
+		ss    = streamstore.NewStreamer(kw, creds.AzureTenantID, path.OneDriveService)
+	)
+
+	err = ss.Read(ctx, ssid, streamstore.DetailsReader(details.UnmarshalTo(&deets)), fault.New(true))
+	require.NoError(t, err, clues.ToCore(err))
+
+	for _, ent := range deets.Entries {
+		assert.Contains(t, ent.RepoRef, incBO.ResourceOwner.ID())
+	}
+}
+
 // ---------------------------------------------------------------------------
 // SharePoint
 // ---------------------------------------------------------------------------

src/internal/operations/backup_test.go

@@ -101,6 +101,7 @@ func (mbu mockBackupConsumer) ConsumeBackupCollections(
 	excluded map[string]map[string]struct{},
 	tags map[string]string,
 	buildTreeWithBase bool,
+	_ kopia.SubtreeMigrator,
 	errs *fault.Bus,
 ) (*kopia.BackupStats, *details.Builder, kopia.DetailsMergeInfoer, error) {
 	if mbu.checkFunc != nil {
@@ -624,6 +625,7 @@ func (suite *BackupOpUnitSuite) TestBackupOperation_ConsumeBackupDataCollections
 				nil,
 				model.StableID(""),
 				true,
+				nil,
 				fault.New(true))
 		})
 	}

src/internal/operations/inject/inject.go

@@ -36,6 +36,7 @@ type (
 			excluded map[string]map[string]struct{},
 			tags map[string]string,
 			buildTreeWithBase bool,
+			stm kopia.SubtreeMigrator,
 			errs *fault.Bus,
 		) (*kopia.BackupStats, *details.Builder, kopia.DetailsMergeInfoer, error)
 	}

src/internal/operations/manifests.go

@@ -2,6 +2,7 @@ package operations
 
 import (
 	"context"
+	"fmt"
 
 	"github.com/alcionai/clues"
 	"github.com/kopia/kopia/repo/manifest"
@@ -93,20 +94,6 @@ func produceManifestsAndMetadata(
 		return ms, nil, false, nil
 	}
 
-	// We only need to check that we have 1:1 reason:base if we're doing an
-	// incremental with associated metadata. This ensures that we're only sourcing
-	// data from a single Point-In-Time (base) for each incremental backup.
-	//
-	// TODO(ashmrtn): This may need updating if we start sourcing item backup
-	// details from previous snapshots when using kopia-assisted incrementals.
-	if err := verifyDistinctBases(ctx, ms); err != nil {
-		logger.Ctx(ctx).With("error", err).Infow(
-			"unioned snapshot collision, falling back to full backup",
-			clues.In(ctx).Slice()...)
-
-		return ms, nil, false, nil
-	}
-
 	for _, man := range ms {
 		if len(man.IncompleteReason) > 0 {
 			continue
@@ -163,6 +150,7 @@ func produceManifestsAndMetadata(
 		LogFaultErrors(ctx, fb.Errors(), "collecting metadata")
 
 		if err != nil && !errors.Is(err, data.ErrNotFound) {
+			fmt.Printf("\n-----\nCOLLECTING METADATA %+v\n-----\n", err)
 			// prior metadata isn't guaranteed to exist.
 			// if it doesn't, we'll just have to do a
 			// full backup for that data.
@@ -234,6 +222,8 @@ func unionManifests(
 
 	// backfill from the fallback where necessary
 	for _, m := range fallback {
+		useReasons := []kopia.Reason{}
+
 		for _, r := range m.Reasons {
 			k := r.Service.String() + r.Category.String()
 			t := tups[k]
@@ -245,6 +235,8 @@ func unionManifests(
 				continue
 			}
 
+			useReasons = append(useReasons, r)
+
 			if len(m.IncompleteReason) > 0 && t.incomplete == nil {
 				t.incomplete = m
 			} else if len(m.IncompleteReason) == 0 {
@@ -253,6 +245,10 @@ func unionManifests(
 
 			tups[k] = t
 		}
+
+		if len(m.IncompleteReason) == 0 && len(useReasons) > 0 {
+			m.Reasons = useReasons
+		}
 	}
 
 	// collect the results into a single slice of manifests

src/internal/operations/manifests_test.go

@@ -757,18 +757,20 @@ func (suite *OperationsManifestsUnitSuite) TestProduceManifestsAndMetadata_fallb
 
 	table := []struct {
 		name            string
-		main            []testInput
+		man             []testInput
 		fallback        []testInput
 		reasons         []kopia.Reason
 		fallbackReasons []kopia.Reason
-		categories      []path.CategoryType
+		manCategories   []path.CategoryType
+		fbCategories    []path.CategoryType
 		assertErr       assert.ErrorAssertionFunc
 		expectManIDs    []string
 		expectNilMans   bool
+		expectReasons   map[string][]path.CategoryType
 	}{
 		{
 			name: "only mans, no fallbacks",
-			main: []testInput{
+			man: []testInput{
 				{
 					id: manComplete,
 				},
@@ -777,8 +779,13 @@ func (suite *OperationsManifestsUnitSuite) TestProduceManifestsAndMetadata_fallb
 					incomplete: true,
 				},
 			},
-			categories:   []path.CategoryType{path.EmailCategory},
+			manCategories: []path.CategoryType{path.EmailCategory},
+			fbCategories:  []path.CategoryType{path.EmailCategory},
 			expectManIDs:  []string{manComplete, manIncomplete},
+			expectReasons: map[string][]path.CategoryType{
+				manComplete:   {path.EmailCategory},
+				manIncomplete: {path.EmailCategory},
+			},
 		},
 		{
 			name: "no mans, only fallbacks",
@@ -791,12 +798,17 @@ func (suite *OperationsManifestsUnitSuite) TestProduceManifestsAndMetadata_fallb
 					incomplete: true,
 				},
 			},
-			categories:   []path.CategoryType{path.EmailCategory},
+			manCategories: []path.CategoryType{path.EmailCategory},
+			fbCategories:  []path.CategoryType{path.EmailCategory},
 			expectManIDs:  []string{fbComplete, fbIncomplete},
+			expectReasons: map[string][]path.CategoryType{
+				fbComplete:   {path.EmailCategory},
+				fbIncomplete: {path.EmailCategory},
+			},
 		},
 		{
 			name: "complete mans and fallbacks",
-			main: []testInput{
+			man: []testInput{
 				{
 					id: manComplete,
 				},
@@ -806,12 +818,16 @@ func (suite *OperationsManifestsUnitSuite) TestProduceManifestsAndMetadata_fallb
 					id: fbComplete,
 				},
 			},
-			categories:   []path.CategoryType{path.EmailCategory},
+			manCategories: []path.CategoryType{path.EmailCategory},
+			fbCategories:  []path.CategoryType{path.EmailCategory},
 			expectManIDs:  []string{manComplete},
+			expectReasons: map[string][]path.CategoryType{
+				manComplete: {path.EmailCategory},
+			},
 		},
 		{
 			name: "incomplete mans and fallbacks",
-			main: []testInput{
+			man: []testInput{
 				{
 					id:         manIncomplete,
 					incomplete: true,
@@ -823,12 +839,16 @@ func (suite *OperationsManifestsUnitSuite) TestProduceManifestsAndMetadata_fallb
 					incomplete: true,
 				},
 			},
-			categories:   []path.CategoryType{path.EmailCategory},
+			manCategories: []path.CategoryType{path.EmailCategory},
+			fbCategories:  []path.CategoryType{path.EmailCategory},
 			expectManIDs:  []string{manIncomplete},
+			expectReasons: map[string][]path.CategoryType{
+				manIncomplete: {path.EmailCategory},
+			},
 		},
 		{
 			name: "complete and incomplete mans and fallbacks",
-			main: []testInput{
+			man: []testInput{
 				{
 					id: manComplete,
 				},
@@ -846,12 +866,17 @@ func (suite *OperationsManifestsUnitSuite) TestProduceManifestsAndMetadata_fallb
 					incomplete: true,
 				},
 			},
-			categories:   []path.CategoryType{path.EmailCategory},
+			manCategories: []path.CategoryType{path.EmailCategory},
+			fbCategories:  []path.CategoryType{path.EmailCategory},
 			expectManIDs:  []string{manComplete, manIncomplete},
+			expectReasons: map[string][]path.CategoryType{
+				manComplete:   {path.EmailCategory},
+				manIncomplete: {path.EmailCategory},
+			},
 		},
 		{
 			name: "incomplete mans, complete fallbacks",
-			main: []testInput{
+			man: []testInput{
 				{
 					id:         manIncomplete,
 					incomplete: true,
@@ -862,12 +887,17 @@ func (suite *OperationsManifestsUnitSuite) TestProduceManifestsAndMetadata_fallb
 					id: fbComplete,
 				},
 			},
-			categories:   []path.CategoryType{path.EmailCategory},
+			manCategories: []path.CategoryType{path.EmailCategory},
+			fbCategories:  []path.CategoryType{path.EmailCategory},
 			expectManIDs:  []string{fbComplete, manIncomplete},
+			expectReasons: map[string][]path.CategoryType{
+				fbComplete:    {path.EmailCategory},
+				manIncomplete: {path.EmailCategory},
+			},
 		},
 		{
 			name: "complete mans, incomplete fallbacks",
-			main: []testInput{
+			man: []testInput{
 				{
 					id: manComplete,
 				},
@@ -878,12 +908,16 @@ func (suite *OperationsManifestsUnitSuite) TestProduceManifestsAndMetadata_fallb
 					incomplete: true,
 				},
 			},
-			categories:   []path.CategoryType{path.EmailCategory},
+			manCategories: []path.CategoryType{path.EmailCategory},
+			fbCategories:  []path.CategoryType{path.EmailCategory},
 			expectManIDs:  []string{manComplete},
+			expectReasons: map[string][]path.CategoryType{
+				manComplete: {path.EmailCategory},
+			},
 		},
 		{
 			name: "complete mans, complete fallbacks, multiple reasons",
-			main: []testInput{
+			man: []testInput{
 				{
 					id: manComplete,
 				},
@@ -893,8 +927,52 @@ func (suite *OperationsManifestsUnitSuite) TestProduceManifestsAndMetadata_fallb
 					id: fbComplete,
 				},
 			},
-			categories:   []path.CategoryType{path.EmailCategory, path.ContactsCategory},
+			manCategories: []path.CategoryType{path.EmailCategory, path.ContactsCategory},
+			fbCategories:  []path.CategoryType{path.EmailCategory, path.ContactsCategory},
 			expectManIDs:  []string{manComplete},
+			expectReasons: map[string][]path.CategoryType{
+				manComplete: {path.EmailCategory, path.ContactsCategory},
+			},
+		},
+		{
+			name: "complete mans, complete fallbacks, distinct reasons",
+			man: []testInput{
+				{
+					id: manComplete,
+				},
+			},
+			fallback: []testInput{
+				{
+					id: fbComplete,
+				},
+			},
+			manCategories: []path.CategoryType{path.ContactsCategory},
+			fbCategories:  []path.CategoryType{path.EmailCategory},
+			expectManIDs:  []string{manComplete, fbComplete},
+			expectReasons: map[string][]path.CategoryType{
+				manComplete: {path.ContactsCategory},
+				fbComplete:  {path.EmailCategory},
+			},
+		},
+		{
+			name: "fb has superset of mans reasons",
+			man: []testInput{
+				{
+					id: manComplete,
+				},
+			},
+			fallback: []testInput{
+				{
+					id: fbComplete,
+				},
+			},
+			manCategories: []path.CategoryType{path.ContactsCategory},
+			fbCategories:  []path.CategoryType{path.EmailCategory, path.ContactsCategory, path.EventsCategory},
+			expectManIDs:  []string{manComplete, fbComplete},
+			expectReasons: map[string][]path.CategoryType{
+				manComplete: {path.ContactsCategory},
+				fbComplete:  {path.EmailCategory, path.EventsCategory},
+			},
 		},
 	}
 	for _, test := range table {
@@ -907,7 +985,7 @@ func (suite *OperationsManifestsUnitSuite) TestProduceManifestsAndMetadata_fallb
 			mainReasons := []kopia.Reason{}
 			fbReasons := []kopia.Reason{}
 
-			for _, cat := range test.categories {
+			for _, cat := range test.manCategories {
 				mainReasons = append(
 					mainReasons,
 					kopia.Reason{
@@ -915,7 +993,9 @@ func (suite *OperationsManifestsUnitSuite) TestProduceManifestsAndMetadata_fallb
 						Service:       path.ExchangeService,
 						Category:      cat,
 					})
+			}
 
+			for _, cat := range test.fbCategories {
 				fbReasons = append(
 					fbReasons,
 					kopia.Reason{
@@ -927,7 +1007,7 @@ func (suite *OperationsManifestsUnitSuite) TestProduceManifestsAndMetadata_fallb
 
 			mans := []*kopia.ManifestEntry{}
 
-			for _, m := range test.main {
+			for _, m := range test.man {
 				incomplete := ""
 				if m.incomplete {
 					incomplete = "ir"
@@ -959,8 +1039,19 @@ func (suite *OperationsManifestsUnitSuite) TestProduceManifestsAndMetadata_fallb
 			assert.False(t, b, "no-metadata is forced for this test")
 
 			manIDs := []string{}
+
 			for _, m := range mans {
 				manIDs = append(manIDs, string(m.ID))
+
+				reasons, ok := test.expectReasons[string(m.ID)]
+				assert.True(t, ok, "unexpected manifest in result: ", m.ID)
+
+				mrs := []path.CategoryType{}
+				for _, r := range m.Reasons {
+					mrs = append(mrs, r.Category)
+				}
+
+				assert.ElementsMatch(t, reasons, mrs)
 			}
 
 			assert.ElementsMatch(t, test.expectManIDs, manIDs)

src/internal/streamstore/streamstore.go

@@ -235,6 +235,7 @@ func write(
 		nil,
 		nil,
 		false,
+		nil,
 		errs)
 	if err != nil {
 		return "", clues.Wrap(err, "storing marshalled bytes in repository")

src/pkg/repository/repository.go

@@ -27,7 +27,6 @@ import (
 	"github.com/alcionai/corso/src/pkg/control"
 	"github.com/alcionai/corso/src/pkg/fault"
 	"github.com/alcionai/corso/src/pkg/logger"
-	"github.com/alcionai/corso/src/pkg/path"
 	"github.com/alcionai/corso/src/pkg/selectors"
 	"github.com/alcionai/corso/src/pkg/storage"
 	"github.com/alcionai/corso/src/pkg/store"
@@ -319,11 +318,6 @@ func (r repository) NewBackupWithLookup(
 		return operations.BackupOperation{}, errors.Wrap(err, "resolving resource owner details")
 	}
 
-	// Exchange and OneDrive need to maintain the user PN as the ID until we're ready to migrate
-	if sel.PathService() != path.SharePointService {
-		ownerID = ownerName
-	}
-
 	// TODO: retrieve display name from gc
 	sel = sel.SetDiscreteOwnerIDName(ownerID, ownerName)