From e6f5b4515d623275c744c580f0223aa072b14469 Mon Sep 17 00:00:00 2001
From: Danny <danny@alcion.ai>
Date: Fri, 29 Jul 2022 12:35:27 -0400
Subject: [PATCH] GC: `exchange.Collection` PopulateFunction refactor without
 TaskList (#441)

exchange.PopulateFunc executed without a tasklist.
---
 .../exchange/exchange_data_collection.go      | 42 +++++++++----------
 src/internal/connector/graph_connector.go     |  7 ++--
 2 files changed, 23 insertions(+), 26 deletions(-)

diff --git a/src/internal/connector/exchange/exchange_data_collection.go b/src/internal/connector/exchange/exchange_data_collection.go
index 417830791..bba1335b8 100644
--- a/src/internal/connector/exchange/exchange_data_collection.go
+++ b/src/internal/connector/exchange/exchange_data_collection.go
@@ -68,40 +68,36 @@ func (eoc *Collection) PopulateCollection(newData *Stream) {
 }
 
 // populateFromTaskList async call to fill DataCollection via channel implementation
-func PopulateFromCollection(
+func (edc *Collection) PopulateFromCollection(
 	ctx context.Context,
 	service graph.Service,
-	collections map[string]*Collection,
 	statusChannel chan<- *support.ConnectorOperationStatus,
 ) {
 	var errs error
 	var attemptedItems, success int
 	objectWriter := kw.NewJsonSerializationWriter()
 
-	for _, edc := range collections {
-
-		for _, task := range edc.jobs {
-			response, err := service.Client().UsersById(edc.user).MessagesById(task).Get()
-			if err != nil {
-				details := support.ConnectorStackErrorTrace(err)
-				errs = support.WrapAndAppend(edc.user, errors.Wrapf(err, "unable to retrieve %s, %s", task, details), errs)
-				continue
-			}
-			err = messageToDataCollection(service.Client(), ctx, objectWriter, edc.data, response, edc.user)
-			success++
-			if err != nil {
-				errs = support.WrapAndAppendf(edc.user, err, errs)
-				success--
-			}
-			if errs != nil && service.ErrPolicy() {
-				break
-			}
+	for _, task := range edc.jobs {
+		response, err := service.Client().UsersById(edc.user).MessagesById(task).Get()
+		if err != nil {
+			details := support.ConnectorStackErrorTrace(err)
+			errs = support.WrapAndAppend(edc.user, errors.Wrapf(err, "unable to retrieve item %s; details %s", task, details), errs)
+			continue
+		}
+		err = messageToDataCollection(service.Client(), ctx, objectWriter, edc.data, response, edc.user)
+		success++
+		if err != nil {
+			errs = support.WrapAndAppendf(edc.user, err, errs)
+			success--
+		}
+		if errs != nil && service.ErrPolicy() {
+			break
 		}
-		close(edc.data)
-		attemptedItems += len(edc.jobs)
 	}
+	close(edc.data)
+	attemptedItems += len(edc.jobs)
 
-	status := support.CreateStatus(ctx, support.Backup, attemptedItems, success, len(collections), errs)
+	status := support.CreateStatus(ctx, support.Backup, attemptedItems, success, 1, errs)
 	logger.Ctx(ctx).Debug(status.String())
 	statusChannel <- status
 }
diff --git a/src/internal/connector/graph_connector.go b/src/internal/connector/graph_connector.go
index 0388e17eb..42d4ece0f 100644
--- a/src/internal/connector/graph_connector.go
+++ b/src/internal/connector/graph_connector.go
@@ -348,9 +348,10 @@ func (gc *GraphConnector) serializeMessages(ctx context.Context, user string) (m
 	if err != nil {
 		return nil, support.WrapAndAppend(user, err, err)
 	}
-	// async call to populate
-	go exchange.PopulateFromCollection(ctx, service, collections, gc.statusCh)
-	gc.incrementAwaitingMessages()
+	for _, edc := range collections {
+		go edc.PopulateFromCollection(ctx, service, gc.statusCh)
+		gc.incrementAwaitingMessages()
+	}
 
 	return collections, err
 }