Migrate to idiomatic error handling the first half to the app/channel.go (#9413)

app/channel.go

@@ -38,11 +38,11 @@ func (a *App) JoinDefaultChannels(teamId string, user *model.User, shouldBeAdmin
 
 	var requestor *model.User
 	if userRequestorId != "" {
-		if u := <-a.Srv.Store.User().Get(userRequestorId); u.Err != nil {
+		u := <-a.Srv.Store.User().Get(userRequestorId)
+		if u.Err != nil {
 			return u.Err
-		} else {
-			requestor = u.Data.(*model.User)
 		}
+		requestor = u.Data.(*model.User)
 	}
 
 	defaultChannelList := []string{"town-square"}
@@ -130,13 +130,14 @@ func (a *App) CreateChannelWithUser(channel *model.Channel, userId string) (*mod
 	}
 
 	// Get total number of channels on current team
-	if count, err := a.GetNumberOfChannelsOnTeam(channel.TeamId); err != nil {
+	count, err := a.GetNumberOfChannelsOnTeam(channel.TeamId)
+	if err != nil {
 		return nil, err
-	} else {
+	}
+
 	if int64(count+1) > *a.Config().TeamSettings.MaxChannelsPerTeam {
 		return nil, model.NewAppError("CreateChannelWithUser", "api.channel.create_channel.max_channel_limit.app_error", map[string]interface{}{"MaxChannelsPerTeam": *a.Config().TeamSettings.MaxChannelsPerTeam}, "", http.StatusBadRequest)
 	}
-	}
 
 	channel.CreatorId = userId
 
@@ -176,9 +177,11 @@ func (a *App) RenameChannel(channel *model.Channel, newChannelName string, newDi
 }
 
 func (a *App) CreateChannel(channel *model.Channel, addMember bool) (*model.Channel, *model.AppError) {
-	if result := <-a.Srv.Store.Channel().Save(channel, *a.Config().TeamSettings.MaxChannelsPerTeam); result.Err != nil {
+	result := <-a.Srv.Store.Channel().Save(channel, *a.Config().TeamSettings.MaxChannelsPerTeam)
+	if result.Err != nil {
 		return nil, result.Err
-	} else {
+	}
+
 	sc := result.Data.(*model.Channel)
 
 	if addMember {
@@ -211,17 +214,17 @@ func (a *App) CreateChannel(channel *model.Channel, addMember bool) (*model.Chan
 	}
 
 	return sc, nil
-	}
 }
 
 func (a *App) CreateDirectChannel(userId string, otherUserId string) (*model.Channel, *model.AppError) {
-	if channel, err := a.createDirectChannel(userId, otherUserId); err != nil {
+	channel, err := a.createDirectChannel(userId, otherUserId)
+	if err != nil {
 		if err.Id == store.CHANNEL_EXISTS_ERROR {
 			return channel, nil
-		} else {
+		}
 		return nil, err
 	}
-	} else {
+
 	a.WaitForChannelMembership(channel.Id, userId)
 
 	a.InvalidateCacheForUser(userId)
@@ -242,7 +245,6 @@ func (a *App) CreateDirectChannel(userId string, otherUserId string) (*model.Cha
 	a.Publish(message)
 
 	return channel, nil
-	}
 }
 
 func (a *App) createDirectChannel(userId string, otherUserId string) (*model.Channel, *model.AppError) {
@@ -257,13 +259,14 @@ func (a *App) createDirectChannel(userId string, otherUserId string) (*model.Cha
 		return nil, model.NewAppError("CreateDirectChannel", "api.channel.create_direct_channel.invalid_user.app_error", nil, otherUserId, http.StatusBadRequest)
 	}
 
-	if result := <-a.Srv.Store.Channel().CreateDirectChannel(userId, otherUserId); result.Err != nil {
+	result := <-a.Srv.Store.Channel().CreateDirectChannel(userId, otherUserId)
+	if result.Err != nil {
 		if result.Err.Id == store.CHANNEL_EXISTS_ERROR {
 			return result.Data.(*model.Channel), result.Err
-		} else {
+		}
 		return nil, result.Err
 	}
-	} else {
+
 	channel := result.Data.(*model.Channel)
 
 	if result := <-a.Srv.Store.ChannelMemberHistory().LogJoinEvent(userId, channel.Id, model.GetMillis()); result.Err != nil {
@@ -274,11 +277,13 @@ func (a *App) createDirectChannel(userId string, otherUserId string) (*model.Cha
 	}
 
 	return channel, nil
-	}
 }
 
 func (a *App) WaitForChannelMembership(channelId string, userId string) {
-	if len(a.Config().SqlSettings.DataSourceReplicas) > 0 {
+	if len(a.Config().SqlSettings.DataSourceReplicas) == 0 {
+		return
+	}
+
 	now := model.GetMillis()
 
 	for model.GetMillis()-now < 12000 {
@@ -299,17 +304,17 @@ func (a *App) WaitForChannelMembership(channelId string, userId string) {
 	}
 
 	mlog.Error(fmt.Sprintf("WaitForChannelMembership giving up channelId=%v userId=%v", channelId, userId), mlog.String("user_id", userId))
-	}
 }
 
 func (a *App) CreateGroupChannel(userIds []string, creatorId string) (*model.Channel, *model.AppError) {
-	if channel, err := a.createGroupChannel(userIds, creatorId); err != nil {
+	channel, err := a.createGroupChannel(userIds, creatorId)
+	if err != nil {
 		if err.Id == store.CHANNEL_EXISTS_ERROR {
 			return channel, nil
-		} else {
+		}
 		return nil, err
 	}
-	} else {
+
 	for _, userId := range userIds {
 		if userId == creatorId {
 			a.WaitForChannelMembership(channel.Id, creatorId)
@@ -323,7 +328,6 @@ func (a *App) CreateGroupChannel(userIds []string, creatorId string) (*model.Cha
 	a.Publish(message)
 
 	return channel, nil
-	}
 }
 
 func (a *App) createGroupChannel(userIds []string, creatorId string) (*model.Channel, *model.AppError) {
@@ -331,12 +335,11 @@ func (a *App) createGroupChannel(userIds []string, creatorId string) (*model.Cha
 		return nil, model.NewAppError("CreateGroupChannel", "api.channel.create_group.bad_size.app_error", nil, "", http.StatusBadRequest)
 	}
 
-	var users []*model.User
+	result := <-a.Srv.Store.User().GetProfileByIds(userIds, true)
-	if result := <-a.Srv.Store.User().GetProfileByIds(userIds, true); result.Err != nil {
+	if result.Err != nil {
 		return nil, result.Err
-	} else {
-		users = result.Data.([]*model.User)
 	}
+	users := result.Data.([]*model.User)
 
 	if len(users) != len(userIds) {
 		return nil, model.NewAppError("CreateGroupChannel", "api.channel.create_group.bad_user.app_error", nil, "user_ids="+model.ArrayToJson(userIds), http.StatusBadRequest)
@@ -348,13 +351,13 @@ func (a *App) createGroupChannel(userIds []string, creatorId string) (*model.Cha
 		Type:        model.CHANNEL_GROUP,
 	}
 
-	if result := <-a.Srv.Store.Channel().Save(group, *a.Config().TeamSettings.MaxChannelsPerTeam); result.Err != nil {
+	result = <-a.Srv.Store.Channel().Save(group, *a.Config().TeamSettings.MaxChannelsPerTeam)
+	if result.Err != nil {
 		if result.Err.Id == store.CHANNEL_EXISTS_ERROR {
 			return result.Data.(*model.Channel), result.Err
-		} else {
+		}
 		return nil, result.Err
 	}
-	} else {
 	channel := result.Data.(*model.Channel)
 
 	for _, user := range users {
@@ -374,7 +377,6 @@ func (a *App) createGroupChannel(userIds []string, creatorId string) (*model.Cha
 	}
 
 	return channel, nil
-	}
 }
 
 func (a *App) GetGroupChannel(userIds []string) (*model.Channel, *model.AppError) {
@@ -382,12 +384,11 @@ func (a *App) GetGroupChannel(userIds []string) (*model.Channel, *model.AppError
 		return nil, model.NewAppError("GetGroupChannel", "api.channel.create_group.bad_size.app_error", nil, "", http.StatusBadRequest)
 	}
 
-	var users []*model.User
+	result := <-a.Srv.Store.User().GetProfileByIds(userIds, true)
-	if result := <-a.Srv.Store.User().GetProfileByIds(userIds, true); result.Err != nil {
+	if result.Err != nil {
 		return nil, result.Err
-	} else {
-		users = result.Data.([]*model.User)
 	}
+	users := result.Data.([]*model.User)
 
 	if len(users) != len(userIds) {
 		return nil, model.NewAppError("GetGroupChannel", "api.channel.create_group.bad_user.app_error", nil, "user_ids="+model.ArrayToJson(userIds), http.StatusBadRequest)
@@ -402,9 +403,11 @@ func (a *App) GetGroupChannel(userIds []string) (*model.Channel, *model.AppError
 }
 
 func (a *App) UpdateChannel(channel *model.Channel) (*model.Channel, *model.AppError) {
-	if result := <-a.Srv.Store.Channel().Update(channel); result.Err != nil {
+	result := <-a.Srv.Store.Channel().Update(channel)
+	if result.Err != nil {
 		return nil, result.Err
-	} else {
+	}
+
 	a.InvalidateCacheForChannel(channel)
 
 	messageWs := model.NewWebSocketEvent(model.WEBSOCKET_EVENT_CHANNEL_UPDATED, "", channel.Id, "", nil)
@@ -412,7 +415,6 @@ func (a *App) UpdateChannel(channel *model.Channel) (*model.Channel, *model.AppE
 	a.Publish(messageWs)
 
 	return channel, nil
-	}
 }
 
 func (a *App) UpdateChannelScheme(channel *model.Channel) (*model.Channel, *model.AppError) {
@@ -433,9 +435,11 @@ func (a *App) UpdateChannelScheme(channel *model.Channel) (*model.Channel, *mode
 }
 
 func (a *App) UpdateChannelPrivacy(oldChannel *model.Channel, user *model.User) (*model.Channel, *model.AppError) {
-	if channel, err := a.UpdateChannel(oldChannel); err != nil {
+	channel, err := a.UpdateChannel(oldChannel)
+	if err != nil {
 		return channel, err
-	} else {
+	}
+
 	if err := a.postChannelPrivacyMessage(user, channel); err != nil {
 		if channel.Type == model.CHANNEL_OPEN {
 			channel.Type = model.CHANNEL_PRIVATE
@@ -454,7 +458,6 @@ func (a *App) UpdateChannelPrivacy(oldChannel *model.Channel, user *model.User)
 	a.Publish(messageWs)
 
 	return channel, nil
-	}
 }
 
 func (a *App) postChannelPrivacyMessage(user *model.User, channel *model.Channel) *model.AppError {
@@ -480,11 +483,11 @@ func (a *App) postChannelPrivacyMessage(user *model.User, channel *model.Channel
 }
 
 func (a *App) RestoreChannel(channel *model.Channel) (*model.Channel, *model.AppError) {
-	if result := <-a.Srv.Store.Channel().Restore(channel.Id, model.GetMillis()); result.Err != nil {
+	result := <-a.Srv.Store.Channel().Restore(channel.Id, model.GetMillis())
+	if result.Err != nil {
 		return nil, result.Err
-	} else {
-		return channel, nil
 	}
+	return channel, nil
 }
 
 func (a *App) PatchChannel(channel *model.Channel, patch *model.ChannelPatch, userId string) (*model.Channel, *model.AppError) {
@@ -528,11 +531,11 @@ func (a *App) GetSchemeRolesForChannel(channelId string) (string, string, *model
 	}
 
 	if channel.SchemeId != nil && len(*channel.SchemeId) != 0 {
-		if scheme, err := a.GetScheme(*channel.SchemeId); err != nil {
+		scheme, err := a.GetScheme(*channel.SchemeId)
+		if err != nil {
 			return "", "", err
-		} else {
-			return scheme.DefaultChannelUserRole, scheme.DefaultChannelAdminRole, nil
 		}
+		return scheme.DefaultChannelUserRole, scheme.DefaultChannelAdminRole, nil
 	}
 
 	var team *model.Team
@@ -542,11 +545,11 @@ func (a *App) GetSchemeRolesForChannel(channelId string) (string, string, *model
 	}
 
 	if team.SchemeId != nil && len(*team.SchemeId) != 0 {
-		if scheme, err := a.GetScheme(*team.SchemeId); err != nil {
+		scheme, err := a.GetScheme(*team.SchemeId)
+		if err != nil {
 			return "", "", err
-		} else {
-			return scheme.DefaultChannelUserRole, scheme.DefaultChannelAdminRole, nil
 		}
+		return scheme.DefaultChannelUserRole, scheme.DefaultChannelAdminRole, nil
 	}
 
 	return model.CHANNEL_USER_ROLE_ID, model.CHANNEL_ADMIN_ROLE_ID, nil
@@ -569,10 +572,13 @@ func (a *App) UpdateChannelMemberRoles(channelId string, userId string, newRoles
 	member.SchemeAdmin = false
 
 	for _, roleName := range strings.Fields(newRoles) {
-		if role, err := a.GetRoleByName(roleName); err != nil {
+		role, err := a.GetRoleByName(roleName)
+		if err != nil {
 			err.StatusCode = http.StatusBadRequest
 			return nil, err
-		} else if !role.SchemeManaged {
+		}
+
+		if !role.SchemeManaged {
 			// The role is not scheme-managed, so it's OK to apply it to the explicit roles field.
 			newExplicitRoles = append(newExplicitRoles, roleName)
 		} else {
@@ -591,11 +597,11 @@ func (a *App) UpdateChannelMemberRoles(channelId string, userId string, newRoles
 
 	member.ExplicitRoles = strings.Join(newExplicitRoles, " ")
 
-	if result := <-a.Srv.Store.Channel().UpdateMember(member); result.Err != nil {
+	result := <-a.Srv.Store.Channel().UpdateMember(member)
+	if result.Err != nil {
 		return nil, result.Err
-	} else {
-		member = result.Data.(*model.ChannelMember)
 	}
+	member = result.Data.(*model.ChannelMember)
 
 	a.InvalidateCacheForUser(userId)
 	return member, nil
@@ -615,11 +621,11 @@ func (a *App) UpdateChannelMemberSchemeRoles(channelId string, userId string, is
 		member.ExplicitRoles = RemoveRoles([]string{model.CHANNEL_USER_ROLE_ID, model.CHANNEL_ADMIN_ROLE_ID}, member.ExplicitRoles)
 	}
 
-	if result := <-a.Srv.Store.Channel().UpdateMember(member); result.Err != nil {
+	result := <-a.Srv.Store.Channel().UpdateMember(member)
+	if result.Err != nil {
 		return nil, result.Err
-	} else {
-		member = result.Data.(*model.ChannelMember)
 	}
+	member = result.Data.(*model.ChannelMember)
 
 	a.InvalidateCacheForUser(userId)
 	return member, nil
@@ -649,9 +655,11 @@ func (a *App) UpdateChannelMemberNotifyProps(data map[string]string, channelId s
 		member.NotifyProps[model.PUSH_NOTIFY_PROP] = push
 	}
 
-	if result := <-a.Srv.Store.Channel().UpdateMember(member); result.Err != nil {
+	result := <-a.Srv.Store.Channel().UpdateMember(member)
+	if result.Err != nil {
 		return nil, result.Err
-	} else {
+	}
+
 	a.InvalidateCacheForUser(userId)
 	a.InvalidateCacheForChannelMembersNotifyProps(channelId)
 	// Notify the clients that the member notify props changed
@@ -659,7 +667,6 @@ func (a *App) UpdateChannelMemberNotifyProps(data map[string]string, channelId s
 	evt.Add("channelMember", member.ToJson())
 	a.Publish(evt)
 	return member, nil
-	}
 }
 
 func (a *App) DeleteChannel(channel *model.Channel, userId string) *model.AppError {
@@ -676,11 +683,16 @@ func (a *App) DeleteChannel(channel *model.Channel, userId string) *model.AppErr
 		user = uresult.Data.(*model.User)
 	}
 
-	if ihcresult := <-ihc; ihcresult.Err != nil {
+	ihcresult := <-ihc
+	if ihcresult.Err != nil {
 		return ihcresult.Err
-	} else if ohcresult := <-ohc; ohcresult.Err != nil {
+	}
+
+	ohcresult := <-ohc
+	if ohcresult.Err != nil {
 		return ohcresult.Err
-	} else {
+	}
+
 	incomingHooks := ihcresult.Data.([]*model.IncomingWebhook)
 	outgoingHooks := ohcresult.Data.([]*model.OutgoingWebhook)
 
@@ -737,7 +749,6 @@ func (a *App) DeleteChannel(channel *model.Channel, userId string) *model.AppErr
 	message.Add("channel_id", channel.Id)
 	message.Add("delete_at", deleteAt)
 	a.Publish(message)
-	}
 
 	return nil
 }
@@ -784,14 +795,14 @@ func (a *App) AddUserToChannel(user *model.User, channel *model.Channel) (*model
 	tmchan := a.Srv.Store.Team().GetMember(channel.TeamId, user.Id)
 	var teamMember *model.TeamMember
 
-	if result := <-tmchan; result.Err != nil {
+	result := <-tmchan
+	if result.Err != nil {
 		return nil, result.Err
-	} else {
+	}
 	teamMember = result.Data.(*model.TeamMember)
 	if teamMember.DeleteAt > 0 {
 		return nil, model.NewAppError("AddUserToChannel", "api.channel.add_user.to.channel.failed.deleted.app_error", nil, "", http.StatusBadRequest)
 	}
-	}
 
 	newMember, err := a.addUserToChannel(user, channel, teamMember)
 	if err != nil {
@@ -861,11 +872,11 @@ func (a *App) AddChannelMember(userId string, channel *model.Channel, userReques
 
 func (a *App) AddDirectChannels(teamId string, user *model.User) *model.AppError {
 	var profiles []*model.User
-	if result := <-a.Srv.Store.User().GetProfiles(teamId, 0, 100); result.Err != nil {
+	result := <-a.Srv.Store.User().GetProfiles(teamId, 0, 100)
+	if result.Err != nil {
 		return model.NewAppError("AddDirectChannels", "api.user.add_direct_channels_and_forget.failed.error", map[string]interface{}{"UserId": user.Id, "TeamId": teamId, "Error": result.Err.Error()}, "", http.StatusInternalServerError)
-	} else {
-		profiles = result.Data.([]*model.User)
 	}
+	profiles = result.Data.([]*model.User)
 
 	var preferences model.Preferences