[MM-12465] Added capability to export reactions of posts during bulk export (#9600)

* Added capability to export reactions of posts

* Added capability to export reactions of replies of a post

* Added test case to test the reactions of a post

3 files changed, 75 insertions, 1 deletions

diff --git a/app/export.go b/app/export.go
index a7a78cfee..b911954a5 100644
--- a/app/export.go
+++ b/app/export.go
@@ -249,8 +249,15 @@ func (a *App) ExportAllPosts(writer io.Writer) *model.AppError {
 				return err
 			}
 
+			reactions, err := a.BuildPostReactions(post.Id)
+			if err != nil {
+				return err
+			}
+
 			postLine.Post.Replies = replies
 
+			postLine.Post.Reactions = reactions
+
 			if err := a.ExportWriteLine(writer, postLine); err != nil {
 				return err
 			}
@@ -272,8 +279,35 @@ func (a *App) buildPostReplies(postId string) (*[]ReplyImportData, *model.AppErr
 	replyPosts := result.Data.([]*model.ReplyForExport)
 
 	for _, reply := range replyPosts {
-		replies = append(replies, *ImportReplyFromPost(reply))
+		replyImportObject := ImportReplyFromPost(reply)
+		if reply.HasReactions == true {
+			reactionsOfReply, err := a.BuildPostReactions(reply.Id)
+			if err != nil {
+				return nil, err
+			}
+			replyImportObject.Reactions = reactionsOfReply
+		}
+		replies = append(replies, *replyImportObject)
 	}
 
 	return &replies, nil
 }
+
+func (a *App) BuildPostReactions(postId string) (*[]ReactionImportData, *model.AppError) {
+	var reactionsOfPost []ReactionImportData
+
+	result := <-a.Srv.Store.Reaction().GetForPost(postId, true)
+
+	if result.Err != nil {
+		return nil, result.Err
+	}
+
+	reactions := result.Data.([]*model.Reaction)
+
+	for _, reaction := range reactions {
+		reactionsOfPost = append(reactionsOfPost, *ImportReactionFromPost(reaction))
+	}
+
+	return &reactionsOfPost, nil
+
+}
diff --git a/app/export_converters.go b/app/export_converters.go
index cafe360cb..3b536c6e3 100644
--- a/app/export_converters.go
+++ b/app/export_converters.go
@@ -111,3 +111,11 @@ func ImportReplyFromPost(post *model.ReplyForExport) *ReplyImportData {
 		CreateAt: &post.CreateAt,
 	}
 }
+
+func ImportReactionFromPost(reaction *model.Reaction) *ReactionImportData {
+	return &ReactionImportData{
+		User:      &reaction.UserId,
+		EmojiName: &reaction.EmojiName,
+		CreateAt:  &reaction.CreateAt,
+	}
+}
diff --git a/app/export_test.go b/app/export_test.go
new file mode 100644
index 000000000..05b81387a
--- /dev/null
+++ b/app/export_test.go
@@ -0,0 +1,32 @@
+package app
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+
+	"github.com/mattermost/mattermost-server/model"
+)
+
+func TestReactionsOfPost(t *testing.T) {
+	th := Setup().InitBasic()
+	defer th.TearDown()
+
+	post := th.BasicPost
+	post.HasReactions = true
+
+	reactionObject := model.Reaction{
+		UserId:    model.NewId(),
+		PostId:    post.Id,
+		EmojiName: "emoji",
+		CreateAt:  model.GetMillis(),
+	}
+
+	th.App.SaveReactionForPost(&reactionObject)
+	reactionsOfPost, err := th.App.BuildPostReactions(post.Id)
+
+	if err != nil {
+		t.Fatal("should have reactions")
+	}
+
+	assert.Equal(t, reactionObject.EmojiName, *(*reactionsOfPost)[0].EmojiName)
+}