Fix/get all reacted users

app/internal/domain/repository/slack.go

@@ -24,8 +24,19 @@ import (
 )
 
 type SlackRepository interface {
+	// PostMessage send a message to a channel
 	PostMessage(ctx context.Context, channelID, message, ts string) error
+
+	// PostEphemeral sends an ephemeral message to user in a channel
 	PostEphemeral(ctx context.Context, channelID, message, ts, userID string) error
+
+	// GetParentMessage gets Slack message that started the thread
 	GetParentMessage(ctx context.Context, channelID, ts string) (*model.SlackMessage, error)
+
+	// ListUsersEmail fetches users email
 	ListUsersEmail(ctx context.Context, userID []string) ([]*model.SlackUserEmail, error)
+
+	// GetReactions fetches reactions
+	// full: if true always return the complete reaction list
+	GetReactions(ctx context.Context, channelID, ts string, full bool) ([]*model.SlackReaction, error)
 }

app/internal/domain/service/slack_reaction_users.go

@@ -68,18 +68,35 @@ func (s *slackReactionUsersService) ListUsersEmailByReaction(ctx context.Context
 	if err != nil {
 		return nil, err
 	}
-	inviteUserIDs := s.getReactionUserIDs(ctx, msg.Reactions, reactionName)
-	inviteUserEmails, err := s.chunkedListUsersEmail(ctx, inviteUserIDs)
+	if s.isReactionRefetchNeeded(msg.Reactions) {
+		msg.Reactions, err = s.getFullReactions(ctx, channelID, ts)
+		if err != nil {
+			return nil, err
+		}
+	}
+	reactedUserIDs := s.getReactionUserIDs(ctx, msg.Reactions, reactionName)
+	reactedUserEmails, err := s.chunkedListUsersEmail(ctx, reactedUserIDs)
 	if err != nil {
 		return nil, err
 	}
-	return inviteUserEmails, nil
+	return reactedUserEmails, nil
+}
+
+// isReactionRefetchNeeded returns true if more fetches is required
+func (s *slackReactionUsersService) isReactionRefetchNeeded(reactions []*model.SlackReaction) bool {
+	for _, r := range reactions {
+		if r.Count != len(r.UserIDs) {
+			return true
+		}
+	}
+	return false
 }
 
 // getReactionUserIDs get reaction users by reactionName
 func (s *slackReactionUsersService) getReactionUserIDs(ctx context.Context, reactions []*model.SlackReaction, reactionName string) []string {
 	var userIDs []string
 	var targetReactions []*model.SlackReaction
+	// filtered reactions by reactionName
 	for _, reaction := range reactions {
 		rn := slack.ExtractReactionName(reaction.Name)
 		if slack.RemoveSkinToneFromReaction(rn) == reactionName {
@@ -94,3 +111,7 @@ func (s *slackReactionUsersService) getReactionUserIDs(ctx context.Context, reac
 	}
 	return slice.ToStringSet(userIDs)
 }
+
+func (s *slackReactionUsersService) getFullReactions(ctx context.Context, channelID, ts string) ([]*model.SlackReaction, error) {
+	return s.slackRepository.GetReactions(ctx, channelID, ts, true)
+}

app/internal/domain/service/slack_reaction_users_test.go

@@ -41,10 +41,12 @@ func Test_slackReactionUsersService_ListUsersEmailByReaction(t *testing.T) {
 			{
 				Name:    "join",
 				UserIDs: []string{"user01", "user02"},
+				Count:   2,
 			},
 			{
 				Name:    "reactionSample",
 				UserIDs: []string{"user02", "user03"},
+				Count:   2,
 			},
 		},
 	}
@@ -76,6 +78,58 @@ func Test_slackReactionUsersService_ListUsersEmailByReaction(t *testing.T) {
 				{ID: "user03", Email: "[email protected]"},
 			},
 		},
+		{
+			name: "OK: There is difference between len(Reaction.UserIDs) and Reaction.Count",
+			args: args{
+				channelID: "sampleCID", ts: "sampleTs", reactionName: "reactionSample",
+			},
+			prepare: func(msr *mock_repository.MockSlackRepository) {
+				gomock.InOrder(
+					msr.EXPECT().GetParentMessage(gomock.Any(), "sampleCID", "sampleTs").Return(
+						&model.SlackMessage{
+							ChannelID: "sampleCID",
+							Reactions: []*model.SlackReaction{
+								{
+									Name:    "join",
+									UserIDs: []string{"user01", "user02"},
+									Count:   2,
+								},
+								{
+									Name:    "reactionSample",
+									UserIDs: []string{"user02", "user03"},
+									Count:   4, // number of counts that need to be re-fetched
+								},
+							},
+						}, nil),
+					msr.EXPECT().GetReactions(gomock.Any(), "sampleCID", "sampleTs", true).Return(
+						[]*model.SlackReaction{
+							{
+								Name:    "join",
+								UserIDs: []string{"user01", "user02"},
+								Count:   2,
+							},
+							{
+								Name:    "reactionSample",
+								UserIDs: []string{"user02", "user03", "user04", "user05"}, // fully fetched
+								Count:   4,
+							},
+						}, nil),
+					msr.EXPECT().ListUsersEmail(gomock.Any(), []string{"user02", "user03", "user04", "user05"}).Return(
+						[]*model.SlackUserEmail{
+							{ID: "user02", Email: "[email protected]"},
+							{ID: "user03", Email: "[email protected]"},
+							{ID: "user04", Email: "[email protected]"},
+							{ID: "user05", Email: "[email protected]"},
+						}, nil),
+				)
+			},
+			want: []*model.SlackUserEmail{
+				{ID: "user02", Email: "[email protected]"},
+				{ID: "user03", Email: "[email protected]"},
+				{ID: "user04", Email: "[email protected]"},
+				{ID: "user05", Email: "[email protected]"},
+			},
+		},
 		{
 			name: "NG: error in GetParentMessage",
 			args: args{
@@ -104,6 +158,35 @@ func Test_slackReactionUsersService_ListUsersEmailByReaction(t *testing.T) {
 			},
 			wantErr: true,
 		},
+		{
+			name: "NG: error in GetReactions",
+			args: args{
+				channelID: "sampleCID", ts: "sampleTs", reactionName: "reactionSample",
+			},
+			prepare: func(msr *mock_repository.MockSlackRepository) {
+				gomock.InOrder(
+					msr.EXPECT().GetParentMessage(gomock.Any(), "sampleCID", "sampleTs").Return(
+						&model.SlackMessage{
+							ChannelID: "sampleCID",
+							Reactions: []*model.SlackReaction{
+								{
+									Name:    "join",
+									UserIDs: []string{"user01", "user02"},
+									Count:   2,
+								},
+								{
+									Name:    "reactionSample",
+									UserIDs: []string{"user02", "user03"},
+									Count:   4, // number of counts that need to be re-fetched
+								},
+							},
+						}, nil),
+					msr.EXPECT().GetReactions(gomock.Any(), "sampleCID", "sampleTs", true).Return(
+						nil, errors.New("sample_error")),
+				)
+			},
+			wantErr: true,
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {

app/internal/model/slack_message.go

@@ -23,6 +23,7 @@ type SlackMessage struct {
 
 type SlackReaction struct {
 	Name    string
+	Count   int
 	UserIDs []string
 }
 

app/internal/repository/slack.go

@@ -64,6 +64,7 @@ func (r *slackRepository) GetParentMessage(ctx context.Context, channelID, ts st
 			reactions = append(reactions, &model.SlackReaction{
 				Name:    reaction.Name,
 				UserIDs: reaction.Users,
+				Count:   reaction.Count,
 			})
 		}
 		return &model.SlackMessage{
@@ -93,3 +94,19 @@ func (r *slackRepository) ListUsersEmail(ctx context.Context, userID []string) (
 	}
 	return slackUsers, nil
 }
+
+func (r *slackRepository) GetReactions(ctx context.Context, channelID, ts string, full bool) ([]*model.SlackReaction, error) {
+	reactions, err := r.client.GetReaction(ctx, channelID, ts, full)
+	if err != nil {
+		return nil, err
+	}
+	ret := make([]*model.SlackReaction, 0, len(reactions))
+	for _, reaction := range reactions {
+		ret = append(ret, &model.SlackReaction{
+			Name:    reaction.Name,
+			UserIDs: reaction.Users,
+			Count:   reaction.Count,
+		})
+	}
+	return ret, nil
+}

app/pkg/slack/client.go

@@ -28,6 +28,7 @@ type Client interface {
 	PostEphemeral(ctx context.Context, channelID, userID, ts, message string) error
 	GetConversationReplies(ctx context.Context, channelID, ts string) ([]slack.Message, error)
 	GetUsersInfo(ctx context.Context, userID ...string) (*[]slack.User, error)
+	GetReaction(ctx context.Context, channelID, ts string, full bool) ([]slack.ItemReaction, error)
 
 	GetClient() *slack.Client
 	GetAppUserID() string
@@ -118,6 +119,15 @@ func (c *client) GetUsersInfo(ctx context.Context, userID ...string) (*[]slack.U
 	return users, nil
 }
 
+func (c *client) GetReaction(ctx context.Context, channelID, ts string, full bool) ([]slack.ItemReaction, error) {
+	return c.Client.GetReactionsContext(ctx, slack.ItemRef{
+		Channel:   channelID,
+		Timestamp: ts,
+	}, slack.GetReactionsParameters{
+		Full: full,
+	})
+}
+
 func (c *client) GetClient() *slack.Client {
 	return c.Client
 }