[APIv4] add getChannelMembersTimezone (#9286)

* add getChannelMembersTimezone

* update per feedback review

* add delimeter to error

11 files changed, 203 insertions, 7 deletions

diff --git a/api4/channel.go b/api4/channel.go
index 02a7c34b5..e3a5bf703 100644
--- a/api4/channel.go
+++ b/api4/channel.go
@@ -33,7 +33,7 @@ func (api *API) InitChannel() {
 	api.BaseRoutes.Channel.Handle("", api.ApiSessionRequired(deleteChannel)).Methods("DELETE")
 	api.BaseRoutes.Channel.Handle("/stats", api.ApiSessionRequired(getChannelStats)).Methods("GET")
 	api.BaseRoutes.Channel.Handle("/pinned", api.ApiSessionRequired(getPinnedPosts)).Methods("GET")
-
+	api.BaseRoutes.Channel.Handle("/timezones", api.ApiSessionRequired(getChannelMembersTimezones)).Methods("GET")
 	api.BaseRoutes.ChannelForUser.Handle("/unread", api.ApiSessionRequired(getChannelUnread)).Methods("GET")
 
 	api.BaseRoutes.ChannelByName.Handle("", api.ApiSessionRequired(getChannelByName)).Methods("GET")
@@ -821,6 +821,26 @@ func getChannelMembers(c *Context, w http.ResponseWriter, r *http.Request) {
 	w.Write([]byte(members.ToJson()))
 }
 
+func getChannelMembersTimezones(c *Context, w http.ResponseWriter, r *http.Request) {
+	c.RequireChannelId()
+	if c.Err != nil {
+		return
+	}
+
+	if !c.App.SessionHasPermissionToChannel(c.Session, c.Params.ChannelId, model.PERMISSION_READ_CHANNEL) {
+		c.SetPermissionError(model.PERMISSION_READ_CHANNEL)
+		return
+	}
+
+	membersTimezones, err := c.App.GetChannelMembersTimezones(c.Params.ChannelId)
+	if err != nil {
+		c.Err = err
+		return
+	}
+
+	w.Write([]byte(model.ArrayToJson(membersTimezones)))
+}
+
 func getChannelMembersByIds(c *Context, w http.ResponseWriter, r *http.Request) {
 	c.RequireChannelId()
 	if c.Err != nil {
diff --git a/api4/channel_test.go b/api4/channel_test.go
index 918b37c0f..d588c0c25 100644
--- a/api4/channel_test.go
+++ b/api4/channel_test.go
@@ -2335,3 +2335,52 @@ func TestUpdateChannelScheme(t *testing.T) {
 	_, resp = th.SystemAdminClient.UpdateChannelScheme(channel.Id, channelScheme.Id)
 	CheckUnauthorizedStatus(t, resp)
 }
+
+func TestGetChannelMembersTimezones(t *testing.T) {
+	th := Setup().InitBasic().InitSystemAdmin()
+	defer th.TearDown()
+	Client := th.Client
+
+	user := th.BasicUser
+	user.Timezone["useAutomaticTimezone"] = "false"
+	user.Timezone["manualTimezone"] = "XOXO/BLABLA"
+	_, resp := Client.UpdateUser(user)
+	CheckNoError(t, resp)
+
+	user2 := th.BasicUser2
+	user2.Timezone["automaticTimezone"] = "NoWhere/Island"
+	_, resp = th.SystemAdminClient.UpdateUser(user2)
+	CheckNoError(t, resp)
+
+	timezone, resp := Client.GetChannelMembersTimezones(th.BasicChannel.Id)
+	CheckNoError(t, resp)
+	if len(timezone) != 2 {
+		t.Fatal("should return 2 timezones")
+	}
+
+	//both users have same timezone
+	user2.Timezone["automaticTimezone"] = "XOXO/BLABLA"
+	_, resp = th.SystemAdminClient.UpdateUser(user2)
+	CheckNoError(t, resp)
+
+	timezone, resp = Client.GetChannelMembersTimezones(th.BasicChannel.Id)
+	CheckNoError(t, resp)
+	if len(timezone) != 1 {
+		t.Fatal("should return 1 timezone")
+	}
+
+	//no timezone set should return empty
+	user2.Timezone["automaticTimezone"] = ""
+	_, resp = th.SystemAdminClient.UpdateUser(user2)
+	CheckNoError(t, resp)
+
+	user.Timezone["manualTimezone"] = ""
+	_, resp = Client.UpdateUser(user)
+
+	timezone, resp = Client.GetChannelMembersTimezones(th.BasicChannel.Id)
+	CheckNoError(t, resp)
+	if len(timezone) > 0 {
+		t.Fatal("should return 0 timezone")
+	}
+
+}
diff --git a/app/channel.go b/app/channel.go
index 93037cf05..dee856b94 100644
--- a/app/channel.go
+++ b/app/channel.go
@@ -1153,6 +1153,24 @@ func (a *App) GetChannelMembersPage(channelId string, page, perPage int) (*model
 	return result.Data.(*model.ChannelMembers), nil
 }
 
+func (a *App) GetChannelMembersTimezones(channelId string) ([]string, *model.AppError) {
+	result := <-a.Srv.Store.Channel().GetChannelMembersTimezones(channelId)
+	if result.Err != nil {
+		return nil, result.Err
+	}
+	membersTimezones := result.Data.([]map[string]string)
+
+	var timezones []string
+	for _, membersTimezone := range membersTimezones {
+		if membersTimezone["automaticTimezone"] == "" && membersTimezone["manualTimezone"] == "" {
+			continue
+		}
+		timezones = append(timezones, model.GetPreferredTimezone(membersTimezone))
+	}
+
+	return model.RemoveDuplicateStrings(timezones), nil
+}
+
 func (a *App) GetChannelMembersByIds(channelId string, userIds []string) (*model.ChannelMembers, *model.AppError) {
 	result := <-a.Srv.Store.Channel().GetMembersByIds(channelId, userIds)
 	if result.Err != nil {
diff --git a/app/channel_test.go b/app/channel_test.go
index 4b09bbb78..b6f460741 100644
--- a/app/channel_test.go
+++ b/app/channel_test.go
@@ -4,6 +4,7 @@
 package app
 
 import (
+	"strings"
 	"testing"
 
 	"github.com/mattermost/mattermost-server/model"
@@ -709,3 +710,40 @@ func TestRenameChannel(t *testing.T) {
 		})
 	}
 }
+
+func TestGetChannelMembersTimezones(t *testing.T) {
+	th := Setup().InitBasic().InitSystemAdmin()
+	defer th.TearDown()
+
+	userRequestorId := ""
+	postRootId := ""
+	if _, err := th.App.AddChannelMember(th.BasicUser2.Id, th.BasicChannel, userRequestorId, postRootId, false); err != nil {
+		t.Fatal("Failed to add user to channel. Error: " + err.Message)
+	}
+
+	user := th.BasicUser
+	user.Timezone["useAutomaticTimezone"] = "false"
+	user.Timezone["manualTimezone"] = "XOXO/BLABLA"
+	th.App.UpdateUser(user, false)
+
+	user2 := th.BasicUser2
+	user2.Timezone["automaticTimezone"] = "NoWhere/Island"
+	th.App.UpdateUser(user2, false)
+
+	user3 := model.User{Email: strings.ToLower(model.NewId()) + "success+test@example.com", Nickname: "Darth Vader", Username: "vader" + model.NewId(), Password: "passwd1", AuthService: ""}
+	ruser, _ := th.App.CreateUser(&user3)
+	th.App.AddUserToChannel(ruser, th.BasicChannel)
+
+	ruser.Timezone["automaticTimezone"] = "NoWhere/Island"
+	th.App.UpdateUser(ruser, false)
+
+	user4 := model.User{Email: strings.ToLower(model.NewId()) + "success+test@example.com", Nickname: "Darth Vader", Username: "vader" + model.NewId(), Password: "passwd1", AuthService: ""}
+	ruser, _ = th.App.CreateUser(&user4)
+	th.App.AddUserToChannel(ruser, th.BasicChannel)
+
+	timezones, err := th.App.GetChannelMembersTimezones(th.BasicChannel.Id)
+	if err != nil {
+		t.Fatal("Failed to get the timezones for a channel. Error: " + err.Error())
+	}
+	assert.Equal(t, 2, len(timezones))
+}
diff --git a/i18n/en.json b/i18n/en.json
index 6bcfc603f..db325eee0 100644
--- a/i18n/en.json
+++ b/i18n/en.json
@@ -4987,6 +4987,10 @@
     "translation": "Unable to get the channel members"
   },
   {
+    "id": "store.sql_channel.get_timezone.app_error",
+    "translation": "We couldn't get the channel members timezones"
+  },
+  {
     "id": "store.sql_channel.get_members_by_ids.app_error",
     "translation": "Unable to get the channel members"
   },
diff --git a/model/client4.go b/model/client4.go
index 903687ece..6a613b6b3 100644
--- a/model/client4.go
+++ b/model/client4.go
@@ -1746,6 +1746,17 @@ func (c *Client4) GetChannelStats(channelId string, etag string) (*ChannelStats,
 	}
 }
 
+// GetChannelMembersTimezones gets a list of timezones for a channel.
+func (c *Client4) GetChannelMembersTimezones(channelId string) ([]string, *Response) {
+	r, err := c.DoApiGet(c.GetChannelRoute(channelId)+"/timezones", "")
+	if err != nil {
+		return nil, BuildErrorResponse(r, err)
+	}
+
+	defer closeBody(r)
+	return ArrayFromJson(r.Body), BuildResponse(r)
+}
+
 // GetPinnedPosts gets a list of pinned posts.
 func (c *Client4) GetPinnedPosts(channelId string, etag string) (*PostList, *Response) {
 	if r, err := c.DoApiGet(c.GetChannelRoute(channelId)+"/pinned", etag); err != nil {
diff --git a/model/user.go b/model/user.go
index 781bcae66..06ad9294f 100644
--- a/model/user.go
+++ b/model/user.go
@@ -499,11 +499,7 @@ func (u *User) IsSAMLUser() bool {
 }
 
 func (u *User) GetPreferredTimezone() string {
-	if u.Timezone["useAutomaticTimezone"] == "true" {
-		return u.Timezone["automaticTimezone"]
-	}
-
-	return u.Timezone["manualTimezone"]
+	return GetPreferredTimezone(u.Timezone)
 }
 
 // UserFromJson will decode the input and return a User
diff --git a/model/utils.go b/model/utils.go
index 172b78242..849e529c1 100644
--- a/model/utils.go
+++ b/model/utils.go
@@ -564,3 +564,26 @@ func IsDomainName(s string) bool {
 
 	return ok
 }
+
+func RemoveDuplicateStrings(in []string) []string {
+	out := []string{}
+	seen := make(map[string]bool, len(in))
+
+	for _, item := range in {
+		if !seen[item] {
+			out = append(out, item)
+
+			seen[item] = true
+		}
+	}
+
+	return out
+}
+
+func GetPreferredTimezone(timezone StringMap) string {
+	if timezone["useAutomaticTimezone"] == "true" {
+		return timezone["automaticTimezone"]
+	}
+
+	return timezone["manualTimezone"]
+}
diff --git a/store/sqlstore/channel_store.go b/store/sqlstore/channel_store.go
index b1886c428..17ef6d4c9 100644
--- a/store/sqlstore/channel_store.go
+++ b/store/sqlstore/channel_store.go
@@ -1197,7 +1197,7 @@ func (s SqlChannelStore) GetMembers(channelId string, offset, limit int) store.S
 		var dbMembers channelMemberWithSchemeRolesList
 		_, err := s.GetReplica().Select(&dbMembers, CHANNEL_MEMBERS_WITH_SCHEME_SELECT_QUERY+"WHERE ChannelId = :ChannelId LIMIT :Limit OFFSET :Offset", map[string]interface{}{"ChannelId": channelId, "Limit": limit, "Offset": offset})
 		if err != nil {
-			result.Err = model.NewAppError("SqlChannelStore.GetMembers", "store.sql_channel.get_members.app_error", nil, "channel_id="+channelId+err.Error(), http.StatusInternalServerError)
+			result.Err = model.NewAppError("SqlChannelStore.GetMembers", "store.sql_channel.get_members.app_error", nil, "channel_id="+channelId+","+err.Error(), http.StatusInternalServerError)
 			return
 		}
 
@@ -1205,6 +1205,27 @@ func (s SqlChannelStore) GetMembers(channelId string, offset, limit int) store.S
 	})
 }
 
+func (s SqlChannelStore) GetChannelMembersTimezones(channelId string) store.StoreChannel {
+	return store.Do(func(result *store.StoreResult) {
+		var dbMembersTimezone []map[string]string
+		_, err := s.GetReplica().Select(&dbMembersTimezone, `
+					SELECT
+						Users.Timezone
+					FROM
+						ChannelMembers
+					LEFT JOIN
+						Users  ON ChannelMembers.UserId = Id
+					WHERE ChannelId = :ChannelId
+		`, map[string]interface{}{
+			"ChannelId": channelId})
+		if err != nil {
+			result.Err = model.NewAppError("SqlChannelStore.GetChannelMembersTimezones", "store.sql_channel.get_members.app_error", nil, "channel_id="+channelId+","+err.Error(), http.StatusInternalServerError)
+			return
+		}
+		result.Data = dbMembersTimezone
+	})
+}
+
 func (s SqlChannelStore) GetMember(channelId string, userId string) store.StoreChannel {
 	return store.Do(func(result *store.StoreResult) {
 		var dbMember channelMemberWithSchemeRoles
diff --git a/store/store.go b/store/store.go
index e21917345..1e153b422 100644
--- a/store/store.go
+++ b/store/store.go
@@ -147,6 +147,7 @@ type ChannelStore interface {
 	UpdateMember(member *model.ChannelMember) StoreChannel
 	GetMembers(channelId string, offset, limit int) StoreChannel
 	GetMember(channelId string, userId string) StoreChannel
+	GetChannelMembersTimezones(channelId string) StoreChannel
 	GetAllChannelMembersForUser(userId string, allowFromCache bool, includeDeleted bool) StoreChannel
 	InvalidateAllChannelMembersForUser(userId string)
 	IsUserInChannelUseCache(userId string, channelId string) bool
diff --git a/store/storetest/mocks/ChannelStore.go b/store/storetest/mocks/ChannelStore.go
index 1c3a2a8f2..9d42d0b65 100644
--- a/store/storetest/mocks/ChannelStore.go
+++ b/store/storetest/mocks/ChannelStore.go
@@ -442,6 +442,21 @@ func (_m *ChannelStore) GetMember(channelId string, userId string) store.StoreCh
 	return r0
 }
 
+func (_m *ChannelStore) GetChannelMembersTimezones(channelId string) store.StoreChannel {
+	ret := _m.Called(channelId)
+
+	var r0 store.StoreChannel
+	if rf, ok := ret.Get(0).(func(string) store.StoreChannel); ok {
+		r0 = rf(channelId)
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).(store.StoreChannel)
+		}
+	}
+
+	return r0
+}
+
 // GetMemberCount provides a mock function with given fields: channelId, allowFromCache
 func (_m *ChannelStore) GetMemberCount(channelId string, allowFromCache bool) store.StoreChannel {
 	ret := _m.Called(channelId, allowFromCache)