MM-48246 - AB test open RHS with linked board (#22201)

* MM-48246 - AB test open RHS with linked board

* fix linter

* fix go vet complain

* implement pr feedback

* fix mispelling

* remove unnecesary comment

* add pr feedback

* fix translation texts

* fallback for the first system stored value

* implement PR feedback

* prevent calling property from potential null object

* use the default hash id for welcome to boards template

app/team.go

@@ -6,6 +6,7 @@ package app
 import (
 	"bytes"
 	"context"
+	"crypto/md5"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -17,6 +18,7 @@ import (
 	"sort"
 	"strings"
 
+	fb_model "github.com/mattermost/focalboard/server/model"
 	"github.com/mattermost/mattermost-server/v6/app/email"
 	"github.com/mattermost/mattermost-server/v6/app/imaging"
 	"github.com/mattermost/mattermost-server/v6/app/request"
@@ -160,6 +162,128 @@ func (a *App) SoftDeleteAllTeamsExcept(teamID string) *model.AppError {
 	return nil
 }
 
+// MM-48246 A/B test show linked boards
+const preferenceName = "linked_board_created"
+
+func (a *App) shouldCreateOnboardingLinkedBoard(c request.CTX, teamId string) bool {
+	ffEnabled := a.Config().FeatureFlags.OnboardingAutoShowLinkedBoard
+	if !ffEnabled {
+		return false
+	}
+
+	hasBoard, err := a.HasBoardProduct()
+	if err != nil {
+		a.Log().Error("error checking the existence of boards product: ", mlog.Err(err))
+		return false
+	}
+
+	if !hasBoard {
+		a.Log().Warn("board product not found")
+		return false
+	}
+
+	data, sysValErr := a.Srv().Store().System().GetByName(model.PreferenceOnboarding + "_" + preferenceName)
+	if sysValErr != nil {
+		var nfErr *store.ErrNotFound
+		if errors.As(sysValErr, &nfErr) { // if no board has been registered, it can create one for this team
+			return true
+		}
+		a.Log().Error("cannot get the system values", mlog.Err(sysValErr))
+		return false
+	}
+
+	// get the team list and check if the team value has been already stored, if so, no need to create a board in town square in that team
+	teamsList := strings.Split(data.Value, ",")
+	for _, team := range teamsList {
+		if team == teamId {
+			return false
+		}
+	}
+
+	return true
+}
+
+func (a *App) createOnboardingLinkedBoard(c request.CTX, teamId string) (*fb_model.Board, *model.AppError) {
+	const defaultTemplatesTeam = "0"
+
+	// see https://github.com/mattermost/focalboard/blob/main/server/services/store/sqlstore/board.go#L302
+	// and https://github.com/mattermost/mattermost-server/pull/22201#discussion_r1099536430
+	const defaultTemplateTitle = "Welcome to Boards!"
+	welcomeToBoardsTemplateId := fmt.Sprintf("%x", md5.Sum([]byte(defaultTemplateTitle)))
+	userId := c.Session().UserId
+
+	boardServiceItf, ok := a.Srv().services[product.BoardsKey]
+	if !ok {
+		return nil, model.NewAppError("CreateBoard", "app.team.create_onboarding_linked_board.product_key_not_found", nil, "", http.StatusBadRequest)
+	}
+
+	boardService, typeOk := boardServiceItf.(product.BoardsService)
+	if !typeOk {
+		// boardServiceItf is NOT of type product.BoardsService
+		return nil, model.NewAppError("CreateBoard", "app.team.create_onboarding_linked_board.itf_not_of_type", nil, "", http.StatusBadRequest)
+	}
+
+	templates, err := boardService.GetTemplates(defaultTemplatesTeam, userId)
+	if err != nil {
+		return nil, model.NewAppError("CreateBoard", "app.team.create_onboarding_linked_board.error_getting_templates", nil, "", http.StatusBadRequest).Wrap(err)
+	}
+
+	channel, appErr := a.GetChannelByName(c, model.DefaultChannelName, teamId, false)
+	if appErr != nil {
+		return nil, appErr
+	}
+
+	var template *fb_model.Board = nil
+	for _, t := range templates {
+		v := t.Properties["trackingTemplateId"]
+		if v == welcomeToBoardsTemplateId {
+			template = t
+			break
+		}
+	}
+	if template == nil && len(templates) > 0 {
+		template = templates[0]
+	}
+
+	// Duplicate board From template
+	boardsAndBlocks, _, err := boardService.DuplicateBoard(template.ID, userId, teamId, false)
+	if err != nil {
+		return nil, model.NewAppError("CreateBoard", "app.team.create_onboarding_linked_board.error_duplicating_board", nil, "", http.StatusBadRequest).Wrap(err)
+	}
+	if len(boardsAndBlocks.Boards) != 1 {
+		return nil, model.NewAppError("CreateBoard", "app.team.create_onboarding_linked_board.error_no_board", nil, "", http.StatusBadRequest).Wrap(err)
+	}
+
+	// link the board with the channel
+	patchedBoard, err := boardService.PatchBoard(&fb_model.BoardPatch{
+		ChannelID: &channel.Id,
+	}, boardsAndBlocks.Boards[0].ID, userId)
+	if err != nil && patchedBoard == nil {
+		return nil, model.NewAppError("CreateBoard", "app.team.create_onboarding_linked_board.error_patching_board", nil, "", http.StatusBadRequest).Wrap(err)
+	}
+
+	// Save in the system preferences that the board was already created once per team
+	data, sysValErr := a.Srv().Store().System().GetByName(model.PreferenceOnboarding + "_" + preferenceName)
+	if sysValErr != nil {
+		c.Logger().Error("cannot get the system preferences", mlog.Err(sysValErr))
+	}
+
+	teamsList := teamId
+	// if data is not nil, data.Value contains the list of teams where the A/B test has alredy created a channel for town square
+	if data != nil {
+		teamsList = data.Value + "," + teamId
+	}
+
+	if err := a.Srv().Store().System().SaveOrUpdate(&model.System{
+		Name:  model.PreferenceOnboarding + "_" + preferenceName,
+		Value: teamsList,
+	}); err != nil {
+		c.Logger().Warn("encountered error saving user preferences", mlog.Err(err))
+	}
+
+	return patchedBoard, nil
+}
+
 func (a *App) CreateTeam(c request.CTX, team *model.Team) (*model.Team, *model.AppError) {
 	rteam, err := a.ch.srv.teamService.CreateTeam(team)
 	if err != nil {
@@ -191,6 +315,20 @@ func (a *App) CreateTeam(c request.CTX, team *model.Team) (*model.Team, *model.A
 		}
 	}
 
+	// MM-48246 A/B test show linked boards. Create a welcome to boards linked board per user
+	if a.shouldCreateOnboardingLinkedBoard(c, team.Id) {
+		board, aErr := a.createOnboardingLinkedBoard(c, team.Id)
+		if aErr != nil || board == nil {
+			a.Log().Warn("Error creating the linked board, only team created", mlog.Err(err))
+			return rteam, nil
+		}
+
+		if board.ID != "" {
+			logInfo := fmt.Sprintf("Board created with id %s and associated to channel %s in team %s", board.ID, board.ChannelID, team.Id)
+			a.Log().Info(logInfo, mlog.Err(err))
+		}
+	}
+
 	return rteam, nil
 }