use channels api to run backups (#4136)

This is the first in a series of PRs to get v0 backups working for channels.  In this change, the current api enumerators get plugged into the collections handler to produce backup data. Follow-up PRs will:
* hook backup to the CLI
* swap full-item enumeration for id-first-get-later pattern
* populate each message with all its replies on the get-later
* turn on integration testing at the operations and ci layers

---

#### Does this PR need a docs update or release note?

- [x] ⛔ No

#### Type of change

- [x] 🌻 Feature

#### Issue(s)

* #3989

#### Test Plan

- [x] ⚡ Unit test
- [x] 💚 E2E

src/internal/m365/collection/groups/backup.go

@@ -17,7 +17,6 @@ import (
 	"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/services/m365/api"
 )
 
 // TODO: incremental support
@@ -31,7 +30,7 @@ import (
 func CreateCollections(
 	ctx context.Context,
 	bpc inject.BackupProducerConfig,
-	handler BackupHandler,
+	bh backupHandler,
 	tenantID string,
 	scope selectors.GroupsScope,
 	// dps DeltaPaths,
@@ -55,19 +54,15 @@ func CreateCollections(
 		observe.Bulletf("%s", qp.Category))
 	defer close(catProgress)
 
-	// TODO(keepers): probably shouldn't call out channels here specifically.
-	// This should be a generic container handler.  But we don't need
-	// to worry about that until if/when we use this code to get email
-	// conversations as well.
-	// Also, this should be produced by the Handler.
-	// chanPager := handler.NewChannelsPager(qp.ProtectedResource.ID())
-	// TODO(neha): enumerate channels
-	channels := []graph.Displayable{}
+	channels, err := bh.getChannels(ctx)
+	if err != nil {
+		return nil, clues.Stack(err)
+	}
 
 	collections, err := populateCollections(
 		ctx,
 		qp,
-		handler,
+		bh,
 		su,
 		channels,
 		scope,
@@ -88,9 +83,9 @@ func CreateCollections(
 func populateCollections(
 	ctx context.Context,
 	qp graph.QueryParams,
-	bh BackupHandler,
+	bh backupHandler,
 	statusUpdater support.StatusUpdater,
-	channels []graph.Displayable,
+	channels []models.Channelable,
 	scope selectors.GroupsScope,
 	// dps DeltaPaths,
 	ctrlOpts control.Options,
@@ -100,7 +95,6 @@ func populateCollections(
 	channelCollections := map[string]data.BackupCollection{}
 
 	// channel ID -> delta url or folder path lookups
-	// TODO(neha/keepers): figure out if deltas are stored per channel, or per group.
 	// deltaURLs = map[string]string{}
 	// currPaths = map[string]string{}
 	// copy of previousPaths.  every channel present in the slice param
@@ -118,11 +112,12 @@ func populateCollections(
 			return nil, el.Failure()
 		}
 
-		cID := ptr.Val(c.GetId())
 		// delete(tombstones, cID)
 
 		var (
-			err error
+			cID   = ptr.Val(c.GetId())
+			cName = ptr.Val(c.GetDisplayName())
+			err   error
 			// dp          = dps[cID]
 			// prevDelta   = dp.Delta
 			// prevPathStr = dp.Path // do not log: pii; log prevPath instead
@@ -137,10 +132,8 @@ func populateCollections(
 			// })
 		)
 
-		// currPath, locPath
-		// TODO(rkeepers): the handler should provide this functionality.
 		// Only create a collection if the path matches the scope.
-		if !includeContainer(ictx, qp, c, scope, qp.Category) {
+		if !bh.includeContainer(ictx, qp, c, scope) {
 			continue
 		}
 
@@ -154,10 +147,7 @@ func populateCollections(
 
 		// ictx = clues.Add(ictx, "previous_path", prevPath)
 
-		// TODO: the handler should provide this implementation.
-		items, err := collectItems(
-			ctx,
-			bh.NewMessagePager(qp.ProtectedResource.ID(), ptr.Val(c.GetId())))
+		items, _, err := bh.getChannelMessagesDelta(ctx, cID, "")
 		if err != nil {
 			el.AddRecoverable(ctx, clues.Stack(err))
 			continue
@@ -171,15 +161,7 @@ func populateCollections(
 
 		var prevPath path.Path
 
-		// TODO: retrieve from handler
-		currPath, err := path.Builder{}.
-			Append(ptr.Val(c.GetId())).
-			ToDataLayerPath(
-				qp.TenantID,
-				qp.ProtectedResource.ID(),
-				path.GroupsService,
-				qp.Category,
-				true)
+		currPath, err := bh.canonicalPath(path.Builder{}.Append(cID), qp.TenantID)
 		if err != nil {
 			el.AddRecoverable(ctx, clues.Stack(err))
 			continue
@@ -189,7 +171,7 @@ func populateCollections(
 			qp.ProtectedResource.ID(),
 			currPath,
 			prevPath,
-			path.Builder{}.Append(ptr.Val(c.GetDisplayName())),
+			path.Builder{}.Append(cName),
 			qp.Category,
 			statusUpdater,
 			ctrlOpts)
@@ -209,7 +191,7 @@ func populateCollections(
 		// // as the "previous path", for reference in case of a rename or relocation.
 		// currPaths[cID] = currPath.String()
 
-		// FIXME: normally this goes before removal, but linters
+		// FIXME: normally this goes before removal, but the linters require no bottom comments
 		for _, item := range items {
 			edc.added[ptr.Val(item.GetId())] = struct{}{}
 		}
@@ -240,79 +222,3 @@ func populateCollections(
 
 	return channelCollections, el.Failure()
 }
-
-func collectItems(
-	ctx context.Context,
-	pager api.DeltaPager[models.ChatMessageable],
-) ([]models.ChatMessageable, error) {
-	items := []models.ChatMessageable{}
-
-	for {
-		// assume delta urls here, which allows single-token consumption
-		page, err := pager.GetPage(graph.ConsumeNTokens(ctx, graph.SingleGetOrDeltaLC))
-		if err != nil {
-			return nil, graph.Wrap(ctx, err, "getting page")
-		}
-
-		// if graph.IsErrInvalidDelta(err) {
-		// 	logger.Ctx(ctx).Infow("Invalid previous delta link", "link", prevDelta)
-
-		// 	invalidPrevDelta = true
-		// 	newPaths = map[string]string{}
-
-		// 	pager.Reset()
-
-		// 	continue
-		// }
-
-		vals, err := pager.ValuesIn(page)
-		if err != nil {
-			return nil, graph.Wrap(ctx, err, "getting items in page")
-		}
-
-		items = append(items, vals...)
-
-		nextLink, _ := api.NextAndDeltaLink(page)
-
-		// if len(deltaLink) > 0 {
-		// 	newDeltaURL = deltaLink
-		// }
-
-		// Check if there are more items
-		if len(nextLink) == 0 {
-			break
-		}
-
-		logger.Ctx(ctx).Debugw("found nextLink", "next_link", nextLink)
-		pager.SetNext(nextLink)
-	}
-
-	return items, nil
-}
-
-// Returns true if the container passes the scope comparison and should be included.
-// Returns:
-// - the path representing the directory as it should be stored in the repository.
-// - the human-readable path using display names.
-// - true if the path passes the scope comparison.
-func includeContainer(
-	ctx context.Context,
-	qp graph.QueryParams,
-	gd graph.Displayable,
-	scope selectors.GroupsScope,
-	category path.CategoryType,
-) bool {
-	// assume a single-level hierarchy
-	directory := ptr.Val(gd.GetDisplayName())
-
-	// TODO(keepers): awaiting parent branch to update to main
-	ok := scope.Matches(selectors.GroupsCategoryUnknown, directory)
-
-	logger.Ctx(ctx).With(
-		"included", ok,
-		"scope", scope,
-		"match_target", directory,
-	).Debug("backup folder selection filter")
-
-	return ok
-}

src/internal/m365/collection/groups/backup_test.go

@@ -0,0 +1,392 @@
+package groups
+
+import (
+	"context"
+	"fmt"
+	"testing"
+
+	"github.com/alcionai/clues"
+	"github.com/microsoftgraph/msgraph-sdk-go/models"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"github.com/stretchr/testify/suite"
+
+	inMock "github.com/alcionai/corso/src/internal/common/idname/mock"
+	"github.com/alcionai/corso/src/internal/data"
+	"github.com/alcionai/corso/src/internal/m365/collection/groups/testdata"
+	"github.com/alcionai/corso/src/internal/m365/graph"
+	"github.com/alcionai/corso/src/internal/m365/support"
+	"github.com/alcionai/corso/src/internal/operations/inject"
+	"github.com/alcionai/corso/src/internal/tester"
+	"github.com/alcionai/corso/src/internal/tester/tconfig"
+	"github.com/alcionai/corso/src/internal/version"
+	"github.com/alcionai/corso/src/pkg/account"
+	"github.com/alcionai/corso/src/pkg/control"
+	"github.com/alcionai/corso/src/pkg/fault"
+	"github.com/alcionai/corso/src/pkg/path"
+	"github.com/alcionai/corso/src/pkg/selectors"
+	selTD "github.com/alcionai/corso/src/pkg/selectors/testdata"
+	"github.com/alcionai/corso/src/pkg/services/m365/api"
+)
+
+// ---------------------------------------------------------------------------
+// mocks
+// ---------------------------------------------------------------------------
+
+var _ backupHandler = &mockBackupHandler{}
+
+type mockBackupHandler struct {
+	channels     []models.Channelable
+	channelsErr  error
+	messages     []models.ChatMessageable
+	messagesErr  error
+	doNotInclude bool
+}
+
+func (bh mockBackupHandler) getChannels(context.Context) ([]models.Channelable, error) {
+	return bh.channels, bh.channelsErr
+}
+
+func (bh mockBackupHandler) getChannelMessagesDelta(
+	_ context.Context,
+	_, _ string,
+) ([]models.ChatMessageable, api.DeltaUpdate, error) {
+	return bh.messages, api.DeltaUpdate{}, bh.messagesErr
+}
+
+func (bh mockBackupHandler) includeContainer(
+	context.Context,
+	graph.QueryParams,
+	models.Channelable,
+	selectors.GroupsScope,
+) bool {
+	return !bh.doNotInclude
+}
+
+func (bh mockBackupHandler) canonicalPath(
+	folders *path.Builder,
+	tenantID string,
+) (path.Path, error) {
+	return folders.
+		ToDataLayerPath(
+			tenantID,
+			"protectedResource",
+			path.GroupsService,
+			path.ChannelMessagesCategory,
+			false)
+}
+
+// ---------------------------------------------------------------------------
+// Unit Suite
+// ---------------------------------------------------------------------------
+
+type BackupUnitSuite struct {
+	tester.Suite
+	creds account.M365Config
+}
+
+func TestServiceIteratorsUnitSuite(t *testing.T) {
+	suite.Run(t, &BackupUnitSuite{Suite: tester.NewUnitSuite(t)})
+}
+
+func (suite *BackupUnitSuite) SetupSuite() {
+	a := tconfig.NewFakeM365Account(suite.T())
+	m365, err := a.M365Config()
+	require.NoError(suite.T(), err, clues.ToCore(err))
+	suite.creds = m365
+}
+
+func (suite *BackupUnitSuite) TestPopulateCollections() {
+	var (
+		qp = graph.QueryParams{
+			Category:          path.ChannelMessagesCategory, // doesn't matter which one we use.
+			ProtectedResource: inMock.NewProvider("group_id", "user_name"),
+			TenantID:          suite.creds.AzureTenantID,
+		}
+		statusUpdater = func(*support.ControllerOperationStatus) {}
+		allScope      = selectors.NewGroupsBackup(nil).Channels(selectors.Any())[0]
+	)
+
+	table := []struct {
+		name                  string
+		mock                  mockBackupHandler
+		scope                 selectors.GroupsScope
+		failFast              control.FailurePolicy
+		expectErr             require.ErrorAssertionFunc
+		expectColls           int
+		expectNewColls        int
+		expectMetadataColls   int
+		expectDoNotMergeColls int
+	}{
+		{
+			name: "happy path, one container",
+			mock: mockBackupHandler{
+				channels: testdata.StubChannels("one"),
+				messages: testdata.StubChatMessages("msg-one"),
+			},
+			scope:                 allScope,
+			expectErr:             require.NoError,
+			expectColls:           1,
+			expectNewColls:        1,
+			expectMetadataColls:   0,
+			expectDoNotMergeColls: 1,
+		},
+		{
+			name: "happy path, many containers",
+			mock: mockBackupHandler{
+				channels: testdata.StubChannels("one", "two"),
+				messages: testdata.StubChatMessages("msg-one"),
+			},
+			scope:                 allScope,
+			expectErr:             require.NoError,
+			expectColls:           2,
+			expectNewColls:        2,
+			expectMetadataColls:   0,
+			expectDoNotMergeColls: 2,
+		},
+		{
+			name: "no containers pass scope",
+			mock: mockBackupHandler{
+				channels:     testdata.StubChannels("one"),
+				doNotInclude: true,
+			},
+			scope:                 selectors.NewGroupsBackup(nil).Channels(selectors.None())[0],
+			expectErr:             require.NoError,
+			expectColls:           0,
+			expectNewColls:        0,
+			expectMetadataColls:   0,
+			expectDoNotMergeColls: 0,
+		},
+		{
+			name:                  "no channels",
+			mock:                  mockBackupHandler{},
+			scope:                 allScope,
+			expectErr:             require.NoError,
+			expectColls:           0,
+			expectNewColls:        0,
+			expectMetadataColls:   0,
+			expectDoNotMergeColls: 0,
+		},
+		{
+			name: "no channel messages",
+			mock: mockBackupHandler{
+				channels: testdata.StubChannels("one"),
+			},
+			scope:                 allScope,
+			expectErr:             require.NoError,
+			expectColls:           1,
+			expectNewColls:        1,
+			expectMetadataColls:   0,
+			expectDoNotMergeColls: 1,
+		},
+		{
+			name: "err: deleted in flight",
+			mock: mockBackupHandler{
+				channels:    testdata.StubChannels("one"),
+				messagesErr: graph.ErrDeletedInFlight,
+			},
+			scope:                 allScope,
+			expectErr:             require.Error,
+			expectColls:           0,
+			expectNewColls:        0,
+			expectMetadataColls:   0,
+			expectDoNotMergeColls: 0,
+		},
+		{
+			name: "err: other error",
+			mock: mockBackupHandler{
+				channels:    testdata.StubChannels("one"),
+				messagesErr: assert.AnError,
+			},
+			scope:                 allScope,
+			expectErr:             require.Error,
+			expectColls:           0,
+			expectNewColls:        0,
+			expectMetadataColls:   0,
+			expectDoNotMergeColls: 0,
+		},
+	}
+	for _, test := range table {
+		// for _, canMakeDeltaQueries := range []bool{true, false} {
+		name := test.name
+
+		// 	if canMakeDeltaQueries {
+		// 		name += "-delta"
+		// 	} else {
+		// 		name += "-non-delta"
+		// 	}
+
+		suite.Run(name, func() {
+			t := suite.T()
+
+			ctx, flush := tester.NewContext(t)
+			defer flush()
+
+			ctrlOpts := control.Options{FailureHandling: test.failFast}
+			// ctrlOpts.ToggleFeatures.DisableDelta = !canMakeDeltaQueries
+
+			collections, err := populateCollections(
+				ctx,
+				qp,
+				test.mock,
+				statusUpdater,
+				test.mock.channels,
+				test.scope,
+				ctrlOpts,
+				fault.New(true))
+			test.expectErr(t, err, clues.ToCore(err))
+			assert.Len(t, collections, test.expectColls, "number of collections")
+
+			// collection assertions
+
+			deleteds, news, metadatas, doNotMerges := 0, 0, 0, 0
+			for _, c := range collections {
+				if c.FullPath().Service() == path.GroupsMetadataService {
+					metadatas++
+					continue
+				}
+
+				if c.State() == data.DeletedState {
+					deleteds++
+				}
+
+				if c.State() == data.NewState {
+					news++
+				}
+
+				if c.DoNotMergeItems() {
+					doNotMerges++
+				}
+			}
+
+			assert.Zero(t, deleteds, "deleted collections")
+			assert.Equal(t, test.expectNewColls, news, "new collections")
+			assert.Equal(t, test.expectMetadataColls, metadatas, "metadata collections")
+			assert.Equal(t, test.expectDoNotMergeColls, doNotMerges, "doNotMerge collections")
+		})
+	}
+}
+
+// }
+
+// ---------------------------------------------------------------------------
+// Integration tests
+// ---------------------------------------------------------------------------
+
+type BackupIntgSuite struct {
+	tester.Suite
+	resource string
+	tenantID string
+	ac       api.Client
+}
+
+func TestBackupIntgSuite(t *testing.T) {
+	suite.Run(t, &BackupIntgSuite{
+		Suite: tester.NewIntegrationSuite(
+			t,
+			[][]string{tconfig.M365AcctCredEnvs}),
+	})
+}
+
+func (suite *BackupIntgSuite) SetupSuite() {
+	t := suite.T()
+
+	ctx, flush := tester.NewContext(t)
+	defer flush()
+
+	graph.InitializeConcurrencyLimiter(ctx, true, 4)
+
+	suite.resource = tconfig.M365TeamID(t)
+
+	acct := tconfig.NewM365Account(t)
+	creds, err := acct.M365Config()
+	require.NoError(t, err, clues.ToCore(err))
+
+	suite.ac, err = api.NewClient(creds, control.DefaultOptions())
+	require.NoError(t, err, clues.ToCore(err))
+
+	suite.tenantID = creds.AzureTenantID
+}
+
+func (suite *BackupIntgSuite) TestCreateCollections() {
+	var (
+		protectedResource = tconfig.M365GroupID(suite.T())
+		resources         = []string{protectedResource}
+		handler           = NewChannelBackupHandler(protectedResource, suite.ac.Channels())
+	)
+
+	tests := []struct {
+		name                string
+		scope               selectors.GroupsScope
+		channelNames        map[string]struct{}
+		canMakeDeltaQueries bool
+	}{
+		{
+			name:  "channel messages non-delta",
+			scope: selTD.GroupsBackupChannelScope(selectors.NewGroupsBackup(resources))[0],
+			channelNames: map[string]struct{}{
+				selTD.TestChannelName: {},
+			},
+			canMakeDeltaQueries: false,
+		},
+	}
+
+	for _, test := range tests {
+		suite.Run(test.name, func() {
+			t := suite.T()
+
+			ctx, flush := tester.NewContext(t)
+			defer flush()
+
+			ctrlOpts := control.DefaultOptions()
+			ctrlOpts.ToggleFeatures.DisableDelta = !test.canMakeDeltaQueries
+
+			sel := selectors.NewGroupsBackup([]string{protectedResource})
+			sel.Include(selTD.GroupsBackupChannelScope(sel))
+
+			bpc := inject.BackupProducerConfig{
+				LastBackupVersion: version.NoBackup,
+				Options:           ctrlOpts,
+				ProtectedResource: inMock.NewProvider(protectedResource, protectedResource),
+				Selector:          sel.Selector,
+			}
+
+			collections, err := CreateCollections(
+				ctx,
+				bpc,
+				handler,
+				suite.tenantID,
+				test.scope,
+				func(status *support.ControllerOperationStatus) {},
+				fault.New(true))
+			require.NoError(t, err, clues.ToCore(err))
+			require.NotEmpty(t, collections, "must have at least one collection")
+
+			for _, c := range collections {
+				if c.FullPath().Service() == path.GroupsMetadataService {
+					continue
+				}
+
+				require.NotEmpty(t, c.FullPath().Folder(false))
+
+				fmt.Printf("\n-----\nfolder %+v\n-----\n", c.FullPath().Folder(false))
+
+				// TODO(ashmrtn): Remove when LocationPath is made part of BackupCollection
+				// interface.
+				if !assert.Implements(t, (*data.LocationPather)(nil), c) {
+					continue
+				}
+
+				loc := c.(data.LocationPather).LocationPath().String()
+
+				fmt.Printf("\n-----\nloc %+v\n-----\n", c.(data.LocationPather).LocationPath().String())
+
+				require.NotEmpty(t, loc)
+
+				delete(test.channelNames, loc)
+			}
+
+			assert.Empty(t, test.channelNames)
+		})
+	}
+}

src/internal/m365/collection/groups/channel_handler.go

@@ -0,0 +1,65 @@
+package groups
+
+import (
+	"context"
+
+	"github.com/microsoftgraph/msgraph-sdk-go/models"
+
+	"github.com/alcionai/corso/src/internal/common/ptr"
+	"github.com/alcionai/corso/src/internal/m365/graph"
+	"github.com/alcionai/corso/src/pkg/path"
+	"github.com/alcionai/corso/src/pkg/selectors"
+	"github.com/alcionai/corso/src/pkg/services/m365/api"
+)
+
+var _ backupHandler = &channelsBackupHandler{}
+
+type channelsBackupHandler struct {
+	ac                api.Channels
+	protectedResource string
+}
+
+func NewChannelBackupHandler(
+	protectedResource string,
+	ac api.Channels,
+) channelsBackupHandler {
+	return channelsBackupHandler{
+		ac:                ac,
+		protectedResource: protectedResource,
+	}
+}
+
+func (bh channelsBackupHandler) getChannels(
+	ctx context.Context,
+) ([]models.Channelable, error) {
+	return bh.ac.GetChannels(ctx, bh.protectedResource)
+}
+
+func (bh channelsBackupHandler) getChannelMessagesDelta(
+	ctx context.Context,
+	channelID, prevDelta string,
+) ([]models.ChatMessageable, api.DeltaUpdate, error) {
+	return bh.ac.GetChannelMessagesDelta(ctx, bh.protectedResource, channelID, prevDelta)
+}
+
+func (bh channelsBackupHandler) includeContainer(
+	ctx context.Context,
+	qp graph.QueryParams,
+	ch models.Channelable,
+	scope selectors.GroupsScope,
+) bool {
+	return scope.Matches(selectors.GroupsChannel, ptr.Val(ch.GetDisplayName()))
+}
+
+func (bh channelsBackupHandler) canonicalPath(
+	folders *path.Builder,
+	tenantID string,
+) (path.Path, error) {
+	return folders.
+		ToDataLayerPath(
+			tenantID,
+			bh.protectedResource,
+			path.GroupsService,
+			path.ChannelMessagesCategory,
+			false)
+}

src/internal/m365/collection/groups/handlers.go

@@ -3,38 +3,39 @@ package groups
 import (
 	"context"
 
-	"github.com/microsoft/kiota-abstractions-go/serialization"
 	"github.com/microsoftgraph/msgraph-sdk-go/models"
 
+	"github.com/alcionai/corso/src/internal/m365/graph"
+	"github.com/alcionai/corso/src/pkg/path"
+	"github.com/alcionai/corso/src/pkg/selectors"
 	"github.com/alcionai/corso/src/pkg/services/m365/api"
 )
 
-type BackupHandler interface {
-	GetChannelByID(
+type backupHandler interface {
+	// gets all channels for the group
+	getChannels(
 		ctx context.Context,
-		teamID, channelID string,
-	) (models.Channelable, error)
-	NewChannelsPager(
-		teamID string,
-	) api.Pager[models.Channelable]
+	) ([]models.Channelable, error)
 
-	GetMessageByID(
+	// gets all messages by delta in the channel.
+	getChannelMessagesDelta(
 		ctx context.Context,
-		teamID, channelID, itemID string,
-	) (models.ChatMessageable, error)
-	NewMessagePager(
-		teamID, channelID string,
-	) api.DeltaPager[models.ChatMessageable]
+		channelID, prevDelta string,
+	) ([]models.ChatMessageable, api.DeltaUpdate, error)
 
-	GetMessageReplies(
+	// includeContainer evaluates whether the channel is included
+	// in the provided scope.
+	includeContainer(
 		ctx context.Context,
-		teamID, channelID, messageID string,
-	) (serialization.Parsable, error)
-}
-
-type BackupMessagesHandler interface {
-	GetMessage(ctx context.Context, teamID, channelID, itemID string) (models.ChatMessageable, error)
-	NewMessagePager(teamID, channelID string) api.DeltaPager[models.ChatMessageable]
-	GetChannel(ctx context.Context, teamID, channelID string) (models.Channelable, error)
-	GetReply(ctx context.Context, teamID, channelID, messageID string) (serialization.Parsable, error)
+		qp graph.QueryParams,
+		ch models.Channelable,
+		scope selectors.GroupsScope,
+	) bool
+
+	// canonicalPath constructs the service and category specific path for
+	// the given builder.
+	canonicalPath(
+		folders *path.Builder,
+		tenantID string,
+	) (path.Path, error)
 }

src/internal/m365/collection/groups/testdata/channels.go

@@ -0,0 +1,40 @@
+package testdata
+
+import (
+	"github.com/google/uuid"
+	"github.com/microsoftgraph/msgraph-sdk-go/models"
+
+	"github.com/alcionai/corso/src/internal/common/ptr"
+)
+
+func StubChannels(names ...string) []models.Channelable {
+	sl := make([]models.Channelable, 0, len(names))
+
+	for _, name := range names {
+		ch := models.NewChannel()
+		ch.SetDisplayName(ptr.To(name))
+		ch.SetId(ptr.To(uuid.NewString()))
+
+		sl = append(sl, ch)
+	}
+
+	return sl
+}
+
+func StubChatMessages(names ...string) []models.ChatMessageable {
+	sl := make([]models.ChatMessageable, 0, len(names))
+
+	for _, name := range names {
+		cm := models.NewChatMessage()
+		cm.SetId(ptr.To(uuid.NewString()))
+
+		body := models.NewItemBody()
+		body.SetContent(ptr.To(name))
+
+		cm.SetBody(body)
+
+		sl = append(sl, cm)
+	}
+
+	return sl
+}

src/internal/m365/service/groups/backup.go

@@ -10,6 +10,7 @@ import (
 	"github.com/alcionai/corso/src/internal/common/ptr"
 	"github.com/alcionai/corso/src/internal/data"
 	"github.com/alcionai/corso/src/internal/m365/collection/drive"
+	"github.com/alcionai/corso/src/internal/m365/collection/groups"
 	"github.com/alcionai/corso/src/internal/m365/collection/site"
 	"github.com/alcionai/corso/src/internal/m365/graph"
 	"github.com/alcionai/corso/src/internal/m365/support"
@@ -94,6 +95,20 @@ func ProduceBackupCollections(
 				el.AddRecoverable(ctx, err)
 				continue
 			}
+
+		case path.ChannelMessagesCategory:
+			dbcs, err = groups.CreateCollections(
+				ctx,
+				bpc,
+				groups.NewChannelBackupHandler(bpc.ProtectedResource.ID(), ac.Channels()),
+				creds.AzureTenantID,
+				scope,
+				su,
+				errs)
+			if err != nil {
+				el.AddRecoverable(ctx, err)
+				continue
+			}
 		}
 
 		collections = append(collections, dbcs...)

src/pkg/selectors/groups.go

@@ -222,21 +222,24 @@ func (s *groups) AllData() []GroupsScope {
 	return scopes
 }
 
-// Channel produces one or more SharePoint channel scopes, where the channel
+// Channels produces one or more SharePoint channel scopes, where the channel
 // matches upon a given channel by ID or Name.  In order to ensure channel selection
 // this should always be embedded within the Filter() set; include(channel()) will
 // select all items in the channel without further filtering.
 // If any slice contains selectors.Any, that slice is reduced to [selectors.Any]
 // If any slice contains selectors.None, that slice is reduced to [selectors.None]
 // If any slice is empty, it defaults to [selectors.None]
-func (s *groups) Channel(channel string) []GroupsScope {
-	return []GroupsScope{
-		makeInfoScope[GroupsScope](
-			GroupsChannel,
-			GroupsInfoChannel,
-			[]string{channel},
-			filters.Equal),
-	}
+func (s *groups) Channels(channels []string, opts ...option) []GroupsScope {
+	var (
+		scopes = []GroupsScope{}
+		os     = append([]option{pathComparator()}, opts...)
+	)
+
+	scopes = append(
+		scopes,
+		makeScope[GroupsScope](GroupsChannel, channels, os...))
+
+	return scopes
 }
 
 // ChannelMessages produces one or more Groups channel message scopes.

src/pkg/selectors/testdata/groups.go

@@ -4,7 +4,7 @@ import (
 	"github.com/alcionai/corso/src/pkg/selectors"
 )
 
-const TestChannelName = "test"
+const TestChannelName = "Test"
 
 // GroupsBackupFolderScope is the standard folder scope that should be used
 // in integration backups with groups when interacting with libraries.
@@ -15,5 +15,5 @@ func GroupsBackupLibraryFolderScope(sel *selectors.GroupsBackup) []selectors.Gro
 // GroupsBackupChannelScope is the standard folder scope that should be used
 // in integration backups with groups when interacting with channels.
 func GroupsBackupChannelScope(sel *selectors.GroupsBackup) []selectors.GroupsScope {
-	return sel.Channel(TestChannelName)
+	return sel.Channels([]string{TestChannelName})
 }