export ownerCats and fetchPrevSnap (#1741)

## Type of change

- [x] 🐹 Trivial/Minor

## Issue(s)

* #1725

## Test Plan

- [x] ⚡ Unit test

src/internal/connector/exchange/service_iterators.go

@@ -157,7 +157,28 @@ func FilterContainersAndFillCollections(
 		collections[metadataKey] = col
 	}
 
-	return errs
+	// TODO(ashmrtn): getFetchIDFunc functions should probably just return a
+	// multierror and all of the error handling should just use those so that it
+	// all ends up more consistent.
+	merrs := multierror.Append(nil, errs)
+
+	col, err = makeMetadataCollection(
+		qp.Credentials.AzureTenantID,
+		qp.ResourceOwner,
+		qp.Category,
+		deltaTokens,
+		statusUpdater,
+	)
+	if err != nil {
+		merrs = multierror.Append(
+			merrs,
+			errors.Wrap(err, "making metadata collection"),
+		)
+	} else if col != nil {
+		collections[metadataKey] = col
+	}
+
+	return merrs.ErrorOrNil()
 }
 
 func IterativeCollectContactContainers(

src/internal/kopia/snapshot_manager.go

@@ -33,9 +33,9 @@ type snapshotManager interface {
 	LoadSnapshots(ctx context.Context, ids []manifest.ID) ([]*snapshot.Manifest, error)
 }
 
-type ownersCats struct {
-	resourceOwners map[string]struct{}
-	serviceCats    map[string]struct{}
+type OwnersCats struct {
+	ResourceOwners map[string]struct{}
+	ServiceCats    map[string]struct{}
 }
 
 func serviceCatTag(p path.Path) string {
@@ -49,15 +49,15 @@ func makeTagKV(k string) (string, string) {
 // tagsFromStrings returns a map[string]string with tags for all ownersCats
 // passed in. Currently uses placeholder values for each tag because there can
 // be multiple instances of resource owners and categories in a single snapshot.
-func tagsFromStrings(oc *ownersCats) map[string]string {
-	res := make(map[string]string, len(oc.serviceCats)+len(oc.resourceOwners))
+func tagsFromStrings(oc *OwnersCats) map[string]string {
+	res := make(map[string]string, len(oc.ServiceCats)+len(oc.ResourceOwners))
 
-	for k := range oc.serviceCats {
+	for k := range oc.ServiceCats {
 		tk, tv := makeTagKV(k)
 		res[tk] = tv
 	}
 
-	for k := range oc.resourceOwners {
+	for k := range oc.ResourceOwners {
 		tk, tv := makeTagKV(k)
 		res[tk] = tv
 	}
@@ -181,16 +181,16 @@ func fetchPrevManifests(
 	return manifestsSinceLastComplete(mans), nil
 }
 
-// fetchPrevSnapshotManifests returns a set of manifests for complete and maybe
+// FetchPrevSnapshotManifests returns a set of manifests for complete and maybe
 // incomplete snapshots for the given (resource owner, service, category)
 // tuples. Up to two manifests can be returned per tuple: one complete and one
 // incomplete. An incomplete manifest may be returned if it is newer than the
 // newest complete manifest for the tuple. Manifests are deduped such that if
 // multiple tuples match the same manifest it will only be returned once.
-func fetchPrevSnapshotManifests(
+func FetchPrevSnapshotManifests(
 	ctx context.Context,
 	sm snapshotManager,
-	oc *ownersCats,
+	oc *OwnersCats,
 ) []*snapshot.Manifest {
 	mans := map[manifest.ID]*snapshot.Manifest{}
 
@@ -198,10 +198,10 @@ func fetchPrevSnapshotManifests(
 	// there's a previous incomplete snapshot and/or a previous complete snapshot
 	// we can pass in. Can be expanded to return more than the most recent
 	// snapshots, but may require more memory at runtime.
-	for serviceCat := range oc.serviceCats {
+	for serviceCat := range oc.ServiceCats {
 		serviceTagKey, serviceTagValue := makeTagKV(serviceCat)
 
-		for resourceOwner := range oc.resourceOwners {
+		for resourceOwner := range oc.ResourceOwners {
 			resourceOwnerTagKey, resourceOwnerTagValue := makeTagKV(resourceOwner)
 
 			tags := map[string]string{

src/internal/kopia/snapshot_manager_test.go

@@ -35,24 +35,24 @@ var (
 	testUser2  = "user2"
 	testUser3  = "user3"
 
-	testAllUsersAllCats = &ownersCats{
-		resourceOwners: map[string]struct{}{
+	testAllUsersAllCats = &OwnersCats{
+		ResourceOwners: map[string]struct{}{
 			testUser1: {},
 			testUser2: {},
 			testUser3: {},
 		},
-		serviceCats: map[string]struct{}{
+		ServiceCats: map[string]struct{}{
 			testMail:   {},
 			testEvents: {},
 		},
 	}
-	testAllUsersMail = &ownersCats{
-		resourceOwners: map[string]struct{}{
+	testAllUsersMail = &OwnersCats{
+		ResourceOwners: map[string]struct{}{
 			testUser1: {},
 			testUser2: {},
 			testUser3: {},
 		},
-		serviceCats: map[string]struct{}{
+		ServiceCats: map[string]struct{}{
 			testMail: {},
 		},
 	}
@@ -168,7 +168,7 @@ func TestSnapshotFetchUnitSuite(t *testing.T) {
 func (suite *SnapshotFetchUnitSuite) TestFetchPrevSnapshots() {
 	table := []struct {
 		name  string
-		input *ownersCats
+		input *OwnersCats
 		data  []manifestInfo
 		// Use this to denote which manifests in data should be expected. Allows
 		// defining data in a table while not repeating things between data and
@@ -442,7 +442,7 @@ func (suite *SnapshotFetchUnitSuite) TestFetchPrevSnapshots() {
 				}
 			}
 
-			snaps := fetchPrevSnapshotManifests(ctx, msm, test.input)
+			snaps := FetchPrevSnapshotManifests(ctx, msm, test.input)
 
 			expected := make([]*snapshot.Manifest, 0, len(test.expectedIdxs))
 			for _, i := range test.expectedIdxs {
@@ -532,7 +532,7 @@ func (suite *SnapshotFetchUnitSuite) TestFetchPrevSnapshotsWorksWithErrors() {
 		},
 	}
 
-	snaps := fetchPrevSnapshotManifests(ctx, msm, input)
+	snaps := FetchPrevSnapshotManifests(ctx, msm, input)
 
 	// Only 1 snapshot should be chosen because the other two attempts fail.
 	// However, which one is returned is non-deterministic because maps are used.

src/internal/kopia/wrapper.go

@@ -410,11 +410,11 @@ func inflateDirTree(
 	ctx context.Context,
 	collections []data.Collection,
 	progress *corsoProgress,
-) (fs.Directory, *ownersCats, error) {
+) (fs.Directory, *OwnersCats, error) {
 	roots := make(map[string]*treeMap)
-	ownerCats := &ownersCats{
-		resourceOwners: make(map[string]struct{}),
-		serviceCats:    make(map[string]struct{}),
+	ownerCats := &OwnersCats{
+		ResourceOwners: make(map[string]struct{}),
+		ServiceCats:    make(map[string]struct{}),
 	}
 
 	for _, s := range collections {
@@ -423,8 +423,8 @@ func inflateDirTree(
 		}
 
 		serviceCat := serviceCatTag(s.FullPath())
-		ownerCats.serviceCats[serviceCat] = struct{}{}
-		ownerCats.resourceOwners[s.FullPath().ResourceOwner()] = struct{}{}
+		ownerCats.ServiceCats[serviceCat] = struct{}{}
+		ownerCats.ResourceOwners[s.FullPath().ResourceOwner()] = struct{}{}
 
 		itemPath := s.FullPath().Elements()
 
@@ -543,12 +543,12 @@ func (w Wrapper) BackupCollections(
 func (w Wrapper) makeSnapshotWithRoot(
 	ctx context.Context,
 	root fs.Directory,
-	oc *ownersCats,
+	oc *OwnersCats,
 	progress *corsoProgress,
 ) (*BackupStats, error) {
 	var man *snapshot.Manifest
 
-	prevSnaps := fetchPrevSnapshotManifests(ctx, w.c, oc)
+	prevSnaps := FetchPrevSnapshotManifests(ctx, w.c, oc)
 
 	bc := &stats.ByteCounter{}
 

src/internal/kopia/wrapper_test.go

@@ -569,8 +569,8 @@ func (suite *KopiaUnitSuite) TestBuildDirectoryTree() {
 	dirTree, oc, err := inflateDirTree(ctx, collections, progress)
 	require.NoError(t, err)
 
-	assert.Equal(t, expectedServiceCats, oc.serviceCats)
-	assert.Equal(t, expectedResourceOwners, oc.resourceOwners)
+	assert.Equal(t, expectedServiceCats, oc.ServiceCats)
+	assert.Equal(t, expectedResourceOwners, oc.ResourceOwners)
 
 	assert.Equal(t, encodeAsPath(testTenant), dirTree.Name())
 
@@ -670,8 +670,8 @@ func (suite *KopiaUnitSuite) TestBuildDirectoryTree_MixedDirectory() {
 			dirTree, oc, err := inflateDirTree(ctx, test.layout, progress)
 			require.NoError(t, err)
 
-			assert.Equal(t, expectedServiceCats, oc.serviceCats)
-			assert.Equal(t, expectedResourceOwners, oc.resourceOwners)
+			assert.Equal(t, expectedServiceCats, oc.ServiceCats)
+			assert.Equal(t, expectedResourceOwners, oc.ResourceOwners)
 
 			assert.Equal(t, encodeAsPath(testTenant), dirTree.Name())