[MM-22051] Remove To/From JSON (#18070)

* Posts * Add missing translation * Fix internal store marshaling * [MM-22051] Remove To/From JSON (Channels) (#18116) * Channels * Channel members * ChannelSearch * Channel categories, list, sidebar, stats, view * Fix conversions * [MM-22051] Remove To/From JSON (Users) (#18121) * User related structs * Fix return * Team related structures (#18127) * [MM-22051] Remove To/From JSON (Status, Bot, Reaction, Thread, FileInfo) (#18130) * Status * Bot * Reaction * Thread * FileInfo * Some fixes * Translations update from Weblate (#18143) * Translated using Weblate (German) Currently translated at 100.0% (2309 of 2309 strings) Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/de/ * Translated using Weblate (Turkish) Currently translated at 100.0% (2309 of 2309 strings) Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/tr/ * Translated using Weblate (Hungarian) Currently translated at 100.0% (2309 of 2309 strings) Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/hu/ * Update translation files Updated by "Cleanup translation files" hook in Weblate. Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/ Update translation files Updated by "Cleanup translation files" hook in Weblate. Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/ Update translation files Updated by "Cleanup translation files" hook in Weblate. Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/ Update translation files Updated by "Cleanup translation files" hook in Weblate. Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/ * Translated using Weblate (German) Currently translated at 100.0% (2301 of 2301 strings) Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/de/ * Translated using Weblate (Turkish) Currently translated at 100.0% (2301 of 2301 strings) Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/tr/ * Translated using Weblate (Hungarian) Currently translated at 100.0% (2301 of 2301 strings) Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/hu/ * Translated using Weblate (English (Australia)) Currently translated at 100.0% (2301 of 2301 strings) Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/en_AU/ * Translated using Weblate (Bulgarian) Currently translated at 100.0% (2301 of 2301 strings) Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/bg/ * Translated using Weblate (Japanese) Currently translated at 100.0% (2301 of 2301 strings) Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/ja/ * Translated using Weblate (Chinese (Simplified)) Currently translated at 100.0% (2301 of 2301 strings) Translation: mattermost-languages-shipped/mattermost-server Translate-URL: https://translate.mattermost.com/projects/mattermost/mattermost-server_master/zh_Hans/ Co-authored-by: JtheBAB <srast@bioc.uzh.ch> Co-authored-by: Kaya Zeren <kayazeren@gmail.com> Co-authored-by: Tóth Csaba // Online ERP Hungary Kft <csaba.toth@online-erp.hu> Co-authored-by: Matthew Williams <Matthew.Williams@outlook.com.au> Co-authored-by: Nikolai Zahariev <nikolaiz@yahoo.com> Co-authored-by: kaakaa <stooner.hoe@gmail.com> Co-authored-by: aeomin <lin@aeomin.net> Co-authored-by: Weblate (bot) <hosted@weblate.org> Co-authored-by: JtheBAB <srast@bioc.uzh.ch> Co-authored-by: Kaya Zeren <kayazeren@gmail.com> Co-authored-by: Tóth Csaba // Online ERP Hungary Kft <csaba.toth@online-erp.hu> Co-authored-by: Matthew Williams <Matthew.Williams@outlook.com.au> Co-authored-by: Nikolai Zahariev <nikolaiz@yahoo.com> Co-authored-by: kaakaa <stooner.hoe@gmail.com> Co-authored-by: aeomin <lin@aeomin.net> * [MM-22051] Remove To/From JSON methods from model (#18138) * Scheme * Role * Session * Config * Status * Fix logic * Emoji * GuestsInvite * Group * Command * ClusterInfo * License * Job * System * Plugin * Command2 * IncomingWebhook * OutgoingWebhook * Fix tests * Update traslation * Some fixes * Add missing return * Simplify * Make Config.ToJSONFiltered() return []byte * Make Busy.ToJSON() return []byte * Include error in log * Split logic * [MM-22051] Remove To/From JSON (final) (#18150) * SwitchRequest * PluginEventData * Permalink * PushNotification * SuggestCommand * PluginsResponse * WebSocketMessage * RemoteCluster * SharedChannel * PluginStatuses * InitialLoad * ClusterDiscovery * ClusterStats * MfaSecret * GroupSyncable * SAML * WebSocketRequest * TypingRequest * SecurityBulletin * OAuthApp * IntegrationAction * DataRetention * Preference * FileInfoList * Compliance * Preferences * FileInfoSearchResults * TermsOfService * InstallMarketplacePluginRequest * GitLabUser * UploadSessions * Remove unused helpers * Fix tests * [MM-23280] Fix linting for ToJSON/FromJSON (#18153) * SwitchRequest * PluginEventData * Permalink * PushNotification * SuggestCommand * PluginsResponse * WebSocketMessage * RemoteCluster * SharedChannel * PluginStatuses * InitialLoad * ClusterDiscovery * ClusterStats * MfaSecret * GroupSyncable * SAML * WebSocketRequest * TypingRequest * SecurityBulletin * OAuthApp * IntegrationAction * DataRetention * Preference * FileInfoList * Compliance * Preferences * FileInfoSearchResults * TermsOfService * InstallMarketplacePluginRequest * GitLabUser * UploadSessions * Remove unused helpers * Fix tests * Fix linting for ToJSON/FromJSON * Fix conversions Co-authored-by: Weblate (bot) <hosted@weblate.org> Co-authored-by: JtheBAB <srast@bioc.uzh.ch> Co-authored-by: Kaya Zeren <kayazeren@gmail.com> Co-authored-by: Tóth Csaba // Online ERP Hungary Kft <csaba.toth@online-erp.hu> Co-authored-by: Matthew Williams <Matthew.Williams@outlook.com.au> Co-authored-by: Nikolai Zahariev <nikolaiz@yahoo.com> Co-authored-by: kaakaa <stooner.hoe@gmail.com> Co-authored-by: aeomin <lin@aeomin.net> Co-authored-by: Mattermod <mattermod@users.noreply.github.com>
2021-09-01 14:43:12 +02:00
--- a/app/busy.go
+++ b/app/busy.go
@@ -5,6 +5,7 @@ package app

 import (
 	"encoding/json"
+	"fmt"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -136,7 +137,7 @@ func (b *Busy) ClusterEventChanged(sbs *model.ServerBusyState) {
 	}
 }

-func (b *Busy) ToJson() string {
+func (b *Busy) ToJSON() ([]byte, error) {
 	b.mux.RLock()
 	defer b.mux.RUnlock()

@@ -145,5 +146,10 @@ func (b *Busy) ToJson() string {
 		Expires:   b.expires.Unix(),
 		ExpiresTS: b.expires.UTC().Format(TimestampFormat),
 	}
-	return sbs.ToJson()
+	sbsJSON, jsonErr := json.Marshal(sbs)
+	if jsonErr != nil {
+		return []byte{}, fmt.Errorf("failed to encode server busy state to JSON: %w", jsonErr)
+	}
+
+	return sbsJSON, nil
 }
--- a/app/busy_test.go
+++ b/app/busy_test.go
@@ -4,7 +4,7 @@
 package app

 import (
-	"bytes"
+	"encoding/json"
 	"testing"
 	"time"

@@ -100,11 +100,15 @@ func TestBusyRace(t *testing.T) {
 func compareBusyState(t *testing.T, busy1 *Busy, busy2 *Busy) bool {
 	t.Helper()
 	if busy1.IsBusy() != busy2.IsBusy() {
-		t.Logf("busy1:%s;  busy2:%s\n", busy1.ToJson(), busy2.ToJson())
+		busy1JSON, _ := busy1.ToJSON()
+		busy2JSON, _ := busy2.ToJSON()
+		t.Logf("busy1:%s;  busy2:%s\n", busy1JSON, busy2JSON)
 		return false
 	}
 	if busy1.Expires().Unix() != busy2.Expires().Unix() {
-		t.Logf("busy1:%s;  busy2:%s\n", busy1.ToJson(), busy2.ToJson())
+		busy1JSON, _ := busy1.ToJSON()
+		busy2JSON, _ := busy2.ToJSON()
+		t.Logf("busy1:%s;  busy2:%s\n", busy1JSON, busy2JSON)
 		return false
 	}
 	return true
@@ -116,8 +120,9 @@ type ClusterMock struct {
 }

 func (c *ClusterMock) SendClusterMessage(msg *model.ClusterMessage) {
-	sbs := model.ServerBusyStateFromJson(bytes.NewReader(msg.Data))
-	c.Busy.ClusterEventChanged(sbs)
+	var sbs model.ServerBusyState
+	json.Unmarshal(msg.Data, &sbs)
+	c.Busy.ClusterEventChanged(&sbs)
 }

 func (c *ClusterMock) SendClusterMessageToNode(nodeID string, msg *model.ClusterMessage) error {
--- a/app/channel.go
+++ b/app/channel.go
@@ -5,6 +5,7 @@ package app

 import (
 	"context"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"net/http"
@@ -510,7 +511,7 @@ func (a *App) CreateGroupChannel(userIDs []string, creatorId string) (*model.Cha
 	}

 	message := model.NewWebSocketEvent(model.WebsocketEventGroupAdded, "", channel.Id, "", nil)
-	message.Add("teammate_ids", model.ArrayToJson(userIDs))
+	message.Add("teammate_ids", model.ArrayToJSON(userIDs))
 	a.Publish(message)

 	return channel, nil
@@ -527,7 +528,7 @@ func (a *App) createGroupChannel(userIDs []string) (*model.Channel, *model.AppEr
 	}

 	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)
+		return nil, model.NewAppError("CreateGroupChannel", "api.channel.create_group.bad_user.app_error", nil, "user_ids="+model.ArrayToJSON(userIDs), http.StatusBadRequest)
 	}

 	group := &model.Channel{
@@ -606,7 +607,7 @@ func (a *App) GetGroupChannel(userIDs []string) (*model.Channel, *model.AppError
 	}

 	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)
+		return nil, model.NewAppError("GetGroupChannel", "api.channel.create_group.bad_user.app_error", nil, "user_ids="+model.ArrayToJSON(userIDs), http.StatusBadRequest)
 	}

 	channel, appErr := a.GetChannelByName(model.GetGroupNameFromUserIds(userIDs), "", true)
@@ -636,7 +637,11 @@ func (a *App) UpdateChannel(channel *model.Channel) (*model.Channel, *model.AppE
 	a.invalidateCacheForChannel(channel)

 	messageWs := model.NewWebSocketEvent(model.WebsocketEventChannelUpdated, "", channel.Id, "", nil)
-	messageWs.Add("channel", channel.ToJson())
+	channelJSON, jsonErr := json.Marshal(channel)
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode channel to JSON", mlog.Err(jsonErr))
+	}
+	messageWs.Add("channel", string(channelJSON))
 	a.Publish(messageWs)

 	return channel, nil
@@ -1248,7 +1253,11 @@ func (a *App) UpdateChannelMemberNotifyProps(data map[string]string, channelID s

 	// Notify the clients that the member notify props changed
 	evt := model.NewWebSocketEvent(model.WebsocketEventChannelMemberUpdated, "", "", member.UserId, nil)
-	evt.Add("channelMember", member.ToJson())
+	memberJSON, jsonErr := json.Marshal(member)
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode channel member to JSON", mlog.Err(jsonErr))
+	}
+	evt.Add("channelMember", string(memberJSON))
 	a.Publish(evt)

 	return member, nil
@@ -1273,7 +1282,11 @@ func (a *App) updateChannelMember(member *model.ChannelMember) (*model.ChannelMe

 	// Notify the clients that the member notify props changed
 	evt := model.NewWebSocketEvent(model.WebsocketEventChannelMemberUpdated, "", "", member.UserId, nil)
-	evt.Add("channelMember", member.ToJson())
+	memberJSON, jsonErr := json.Marshal(member)
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode channel member to JSON", mlog.Err(jsonErr))
+	}
+	evt.Add("channelMember", string(memberJSON))
 	a.Publish(evt)

 	return member, nil
@@ -2545,10 +2558,12 @@ func (a *App) MarkChannelAsUnreadFromPost(postID string, userID string, collapse
 				}
 				a.sanitizeProfiles(thread.Participants, false)
 				thread.Post.SanitizeProps()
-
-				payload := thread.ToJson()
+				payload, jsonErr := json.Marshal(thread)
+				if jsonErr != nil {
+					mlog.Warn("Failed to encode thread to JSON")
+				}
 				message := model.NewWebSocketEvent(model.WebsocketEventThreadUpdated, channel.TeamId, "", userID, nil)
-				message.Add("thread", payload)
+				message.Add("thread", string(payload))
 				a.Publish(message)
 			}
 		} else if !threadMembership.Following && followThread {
@@ -2661,10 +2676,13 @@ func (a *App) markChannelAsUnreadFromPostCRTUnsupported(postID string, userID st
 	a.sanitizeProfiles(thread.Participants, false)
 	thread.Post.SanitizeProps()

-	payload := thread.ToJson()
 	if a.isCRTEnabledForUser(userID) {
+		payload, jsonErr := json.Marshal(thread)
+		if jsonErr != nil {
+			mlog.Warn("Failed to encode thread to JSON")
+		}
 		message := model.NewWebSocketEvent(model.WebsocketEventThreadUpdated, channel.TeamId, "", userID, nil)
-		message.Add("thread", payload)
+		message.Add("thread", string(payload))
 		a.Publish(message)
 	}
 	channelUnread, nErr := a.Srv().Store.Channel().UpdateLastViewedAtPost(post, userID, unreadMentions, 0, false, false)
@@ -3190,7 +3208,13 @@ func (a *App) setChannelsMuted(channelIDs []string, userID string, muted bool) (
 		a.invalidateCacheForChannelMembersNotifyProps(member.ChannelId)

 		evt := model.NewWebSocketEvent(model.WebsocketEventChannelMemberUpdated, "", "", member.UserId, nil)
-		evt.Add("channelMember", member.ToJson())
+
+		memberJSON, jsonErr := json.Marshal(member)
+		if jsonErr != nil {
+			mlog.Warn("Failed to encode channel member to JSON", mlog.Err(jsonErr))
+		}
+
+		evt.Add("channelMember", string(memberJSON))
 		a.Publish(evt)
 	}

@@ -3292,7 +3316,11 @@ func (a *App) ClearChannelMembersCache(channelID string) {
 	clearSessionCache := func(channelMember model.ChannelMember) error {
 		a.ClearSessionCacheForUser(channelMember.UserId)
 		message := model.NewWebSocketEvent(model.WebsocketEventChannelMemberUpdated, "", "", channelMember.UserId, nil)
-		message.Add("channelMember", channelMember.ToJson())
+		memberJSON, jsonErr := json.Marshal(channelMember)
+		if jsonErr != nil {
+			mlog.Warn("Failed to encode channel member to JSON", mlog.Err(jsonErr))
+		}
+		message.Add("channelMember", string(memberJSON))
 		a.Publish(message)
 		return nil
 	}
--- a/app/cluster_handlers.go
+++ b/app/cluster_handlers.go
@@ -5,6 +5,7 @@ package app

 import (
 	"bytes"
+	"encoding/json"

 	"github.com/mattermost/mattermost-server/v6/model"
 	"github.com/mattermost/mattermost-server/v6/plugin"
@@ -12,11 +13,19 @@ import (
 )

 func (s *Server) clusterInstallPluginHandler(msg *model.ClusterMessage) {
-	s.installPluginFromData(model.PluginEventDataFromJson(bytes.NewReader(msg.Data)))
+	var data model.PluginEventData
+	if jsonErr := json.Unmarshal(msg.Data, &data); jsonErr != nil {
+		mlog.Warn("Failed to decode from JSON", mlog.Err(jsonErr))
+	}
+	s.installPluginFromData(data)
 }

 func (s *Server) clusterRemovePluginHandler(msg *model.ClusterMessage) {
-	s.removePluginFromData(model.PluginEventDataFromJson(bytes.NewReader(msg.Data)))
+	var data model.PluginEventData
+	if jsonErr := json.Unmarshal(msg.Data, &data); jsonErr != nil {
+		mlog.Warn("Failed to decode from JSON", mlog.Err(jsonErr))
+	}
+	s.removePluginFromData(data)
 }

 func (s *Server) clusterPluginEventHandler(msg *model.ClusterMessage) {
@@ -69,15 +78,19 @@ func (s *Server) registerClusterHandlers() {
 }

 func (s *Server) clusterPublishHandler(msg *model.ClusterMessage) {
-	event := model.WebSocketEventFromJson(bytes.NewReader(msg.Data))
-	if event == nil {
+	event, err := model.WebSocketEventFromJSON(bytes.NewReader(msg.Data))
+	if err != nil {
+		mlog.Warn("Failed to decode event from JSON", mlog.Err(err))
 		return
 	}
 	s.PublishSkipClusterSend(event)
 }

 func (s *Server) clusterUpdateStatusHandler(msg *model.ClusterMessage) {
-	status := model.StatusFromJson(bytes.NewReader(msg.Data))
+	var status model.Status
+	if jsonErr := json.Unmarshal(msg.Data, &status); jsonErr != nil {
+		mlog.Warn("Failed to decode status from JSON")
+	}
 	s.statusCache.Set(status.UserId, status)
 }

@@ -120,7 +133,11 @@ func (s *Server) clusterClearSessionCacheForAllUsersHandler(msg *model.ClusterMe
 }

 func (s *Server) clusterBusyStateChgHandler(msg *model.ClusterMessage) {
-	s.serverBusyStateChanged(model.ServerBusyStateFromJson(bytes.NewReader(msg.Data)))
+	var sbs model.ServerBusyState
+	if jsonErr := json.Unmarshal(msg.Data, &sbs); jsonErr != nil {
+		mlog.Warn("Failed to decode server busy state from JSON", mlog.Err(jsonErr))
+	}
+	s.serverBusyStateChanged(&sbs)
 }

 func (s *Server) invalidateCacheForChannelMembersNotifyPropsSkipClusterSend(channelID string) {
--- a/app/command_autocomplete.go
+++ b/app/command_autocomplete.go
@@ -4,6 +4,7 @@
 package app

 import (
+	"encoding/json"
 	"errors"
 	"fmt"
 	"net/url"
@@ -277,7 +278,10 @@ func (a *App) getDynamicListArgument(c *request.Context, commandArgs *model.Comm
 		return false, parsed, toBeParsed, []model.AutocompleteSuggestion{}
 	}

-	listItems := model.AutocompleteStaticListItemsFromJSON(resp.Body)
+	var listItems []model.AutocompleteListItem
+	if jsonErr := json.NewDecoder(resp.Body).Decode(&listItems); jsonErr != nil {
+		mlog.Warn("Failed to decode from JSON", mlog.Err(jsonErr))
+	}

 	return parseListItems(listItems, parsed, toBeParsed)
 }
--- a/app/email/email.go
+++ b/app/email/email.go
@@ -460,14 +460,14 @@ func (es *Service) SendInviteEmails(team *model.Team, senderName string, senderU

 			token := model.NewToken(
 				TokenTypeTeamInvitation,
-				model.MapToJson(map[string]string{"teamId": team.Id, "email": invite}),
+				model.MapToJSON(map[string]string{"teamId": team.Id, "email": invite}),
 			)

 			tokenProps := make(map[string]string)
 			tokenProps["email"] = invite
 			tokenProps["display_name"] = team.DisplayName
 			tokenProps["name"] = team.Name
-			tokenData := model.MapToJson(tokenProps)
+			tokenData := model.MapToJSON(tokenProps)

 			if err := es.store.Token().Save(token); err != nil {
 				mlog.Error("Failed to send invite email successfully ", mlog.Err(err))
@@ -531,7 +531,7 @@ func (es *Service) SendGuestInviteEmails(team *model.Team, channels []*model.Cha

 			token := model.NewToken(
 				TokenTypeGuestInvitation,
-				model.MapToJson(map[string]string{
+				model.MapToJSON(map[string]string{
 					"teamId":   team.Id,
 					"channels": strings.Join(channelIDs, " "),
 					"email":    invite,
@@ -543,7 +543,7 @@ func (es *Service) SendGuestInviteEmails(team *model.Team, channels []*model.Cha
 			tokenProps["email"] = invite
 			tokenProps["display_name"] = team.DisplayName
 			tokenProps["name"] = team.Name
-			tokenData := model.MapToJson(tokenProps)
+			tokenData := model.MapToJSON(tokenProps)

 			if err := es.store.Token().Save(token); err != nil {
 				mlog.Error("Failed to send invite email successfully ", mlog.Err(err))
--- a/app/emoji.go
+++ b/app/emoji.go
@@ -6,6 +6,7 @@ package app
 import (
 	"bytes"
 	"context"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"image"
@@ -78,7 +79,11 @@ func (a *App) CreateEmoji(sessionUserId string, emoji *model.Emoji, multiPartIma
 	}

 	message := model.NewWebSocketEvent(model.WebsocketEventEmojiAdded, "", "", "", nil)
-	message.Add("emoji", emoji.ToJson())
+	emojiJSON, jsonErr := json.Marshal(emoji)
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode emoji to JSON", mlog.Err(jsonErr))
+	}
+	message.Add("emoji", string(emojiJSON))
 	a.Publish(message)
 	return emoji, nil
 }
--- a/app/group.go
+++ b/app/group.go
@@ -4,10 +4,12 @@
 package app

 import (
+	"encoding/json"
 	"errors"
 	"net/http"

 	"github.com/mattermost/mattermost-server/v6/model"
+	"github.com/mattermost/mattermost-server/v6/shared/mlog"
 	"github.com/mattermost/mattermost-server/v6/store"
 )

@@ -97,7 +99,11 @@ func (a *App) UpdateGroup(group *model.Group) (*model.Group, *model.AppError) {

 	if err == nil {
 		messageWs := model.NewWebSocketEvent(model.WebsocketEventReceivedGroup, "", "", "", nil)
-		messageWs.Add("group", updatedGroup.ToJson())
+		groupJSON, jsonErr := json.Marshal(updatedGroup)
+		if jsonErr != nil {
+			mlog.Warn("Failed to encode group to JSON", mlog.Err(jsonErr))
+		}
+		messageWs.Add("group", string(groupJSON))
 		a.Publish(messageWs)
 	}

@@ -122,7 +128,11 @@ func (a *App) DeleteGroup(groupID string) (*model.Group, *model.AppError) {

 	if err == nil {
 		messageWs := model.NewWebSocketEvent(model.WebsocketEventReceivedGroup, "", "", "", nil)
-		messageWs.Add("group", deletedGroup.ToJson())
+		groupJSON, jsonErr := json.Marshal(deletedGroup)
+		if jsonErr != nil {
+			mlog.Warn("Failed to encode group to JSON", mlog.Err(jsonErr))
+		}
+		messageWs.Add("group", string(groupJSON))
 		a.Publish(messageWs)
 	}

--- a/app/import_validators.go
+++ b/app/import_validators.go
@@ -457,7 +457,7 @@ func validatePostImportData(data *PostImportData, maxPostSize int) *model.AppErr
 		}
 	}

-	if data.Props != nil && utf8.RuneCountInString(model.StringInterfaceToJson(*data.Props)) > model.PostPropsMaxRunes {
+	if data.Props != nil && utf8.RuneCountInString(model.StringInterfaceToJSON(*data.Props)) > model.PostPropsMaxRunes {
 		return model.NewAppError("BulkImport", "app.import.validate_post_import_data.props_too_large.error", nil, "", http.StatusBadRequest)
 	}

--- a/app/integration_action.go
+++ b/app/integration_action.go
@@ -242,7 +242,11 @@ func (a *App) DoPostActionWithCookie(c *request.Context, postID, actionId, userI
 		}
 		return "", nil
 	}
-	resp, appErr = a.DoActionRequest(c, upstreamURL, upstreamRequest.ToJson())
+	requestJSON, jsonErr := json.Marshal(upstreamRequest)
+	if jsonErr != nil {
+		return "", model.NewAppError("DoPostActionWithCookie", "api.marshal_error", nil, jsonErr.Error(), http.StatusInternalServerError)
+	}
+	resp, appErr = a.DoActionRequest(c, upstreamURL, requestJSON)
 	if appErr != nil {
 		return "", appErr
 	}
@@ -530,7 +534,7 @@ type MailToLinkContent struct {
 	MailBody      string `json:"mail_body"`
 }

-func (mlc *MailToLinkContent) ToJson() string {
+func (mlc *MailToLinkContent) ToJSON() string {
 	b, _ := json.Marshal(mlc)
 	return string(b)
 }
@@ -569,7 +573,7 @@ func (a *App) buildWarnMetricMailtoLink(warnMetricId string, user *model.User) s
 		MailBody:      mailBody,
 	}

-	return mailToLinkContent.ToJson()
+	return mailToLinkContent.ToJSON()
 }

 func (a *App) DoLocalRequest(c *request.Context, rawURL string, body []byte) (*http.Response, *model.AppError) {
--- a/app/integration_action_test.go
+++ b/app/integration_action_test.go
@@ -29,8 +29,9 @@ func TestPostActionInvalidURL(t *testing.T) {
 	})

 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		request := model.PostActionIntegrationRequestFromJson(r.Body)
-		assert.NotNil(t, request)
+		var request model.PostActionIntegrationRequest
+		jsonErr := json.NewDecoder(r.Body).Decode(&request)
+		assert.NoError(t, jsonErr)
 	}))
 	defer ts.Close()

@@ -155,8 +156,9 @@ func TestPostAction(t *testing.T) {
 			})

 			ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-				request := model.PostActionIntegrationRequestFromJson(r.Body)
-				assert.NotNil(t, request)
+				var request model.PostActionIntegrationRequest
+				jsonErr := json.NewDecoder(r.Body).Decode(&request)
+				assert.NoError(t, jsonErr)

 				assert.Equal(t, request.UserId, th.BasicUser.Id)
 				assert.Equal(t, request.UserName, th.BasicUser.Username)
@@ -410,8 +412,9 @@ func TestPostActionProps(t *testing.T) {
 	})

 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		request := model.PostActionIntegrationRequestFromJson(r.Body)
-		assert.NotNil(t, request)
+		var request model.PostActionIntegrationRequest
+		jsonErr := json.NewDecoder(r.Body).Decode(&request)
+		assert.NoError(t, jsonErr)

 		fmt.Fprintf(w, `{
 			"update": {
@@ -536,6 +539,8 @@ func TestSubmitInteractiveDialog(t *testing.T) {

 		import (
 			"net/http"
+			"encoding/json"
+
 			"github.com/mattermost/mattermost-server/v6/plugin"
 			"github.com/mattermost/mattermost-server/v6/model"
 		)
@@ -553,7 +558,8 @@ func TestSubmitInteractiveDialog(t *testing.T) {
 				Errors: map[string]string{"name1": errReply},
 			}
 			w.WriteHeader(http.StatusOK)
-			_, _ = w.Write(response.ToJson())
+			responseJSON, _ := json.Marshal(response)
+			_, _ = w.Write(responseJSON)
 		}

 		func main() {
@@ -606,8 +612,9 @@ func TestPostActionRelativeURL(t *testing.T) {
 	defer th.TearDown()

 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		request := model.PostActionIntegrationRequestFromJson(r.Body)
-		assert.NotNil(t, request)
+		var request model.PostActionIntegrationRequest
+		jsonErr := json.NewDecoder(r.Body).Decode(&request)
+		assert.NoError(t, jsonErr)
 		fmt.Fprintf(w, `{"post": {"message": "updated"}, "ephemeral_text": "foo"}`)
 	}))
 	defer ts.Close()
@@ -824,6 +831,8 @@ func TestPostActionRelativePluginURL(t *testing.T) {

 		import (
 			"net/http"
+			"encoding/json" 
+
 			"github.com/mattermost/mattermost-server/v6/plugin"
 			"github.com/mattermost/mattermost-server/v6/model"
 		)
@@ -835,7 +844,8 @@ func TestPostActionRelativePluginURL(t *testing.T) {
 		func (p *MyPlugin) 	ServeHTTP(c *plugin.Context, w http.ResponseWriter, r *http.Request) {
 			response := &model.PostActionIntegrationResponse{}
 			w.WriteHeader(http.StatusOK)
-			_, _ = w.Write(response.ToJson())
+			responseJSON, _ := json.Marshal(response)
+			_, _ = w.Write(responseJSON)
 		}

 		func main() {
--- a/app/license.go
+++ b/app/license.go
@@ -5,9 +5,9 @@ package app

 import (
 	"bytes"
+	"encoding/json"
 	"net/http"
 	"os"
-	"strings"
 	"time"

 	"github.com/dgrijalva/jwt-go"
@@ -100,7 +100,11 @@ func (s *Server) SaveLicense(licenseBytes []byte) (*model.License, *model.AppErr
 	if !success {
 		return nil, model.NewAppError("addLicense", model.InvalidLicenseError, nil, "", http.StatusBadRequest)
 	}
-	license := model.LicenseFromJson(strings.NewReader(licenseStr))
+
+	var license model.License
+	if jsonErr := json.Unmarshal([]byte(licenseStr), &license); jsonErr != nil {
+		return nil, model.NewAppError("addLicense", "api.unmarshal_error", nil, jsonErr.Error(), http.StatusInternalServerError)
+	}

 	uniqueUserCount, err := s.Store.User().Count(model.UserCountOptions{})
 	if err != nil {
@@ -111,11 +115,11 @@ func (s *Server) SaveLicense(licenseBytes []byte) (*model.License, *model.AppErr
 		return nil, model.NewAppError("addLicense", "api.license.add_license.unique_users.app_error", map[string]interface{}{"Users": *license.Features.Users, "Count": uniqueUserCount}, "", http.StatusBadRequest)
 	}

-	if license != nil && license.IsExpired() {
+	if license.IsExpired() {
 		return nil, model.NewAppError("addLicense", model.ExpiredLicenseError, nil, "", http.StatusBadRequest)
 	}

-	if ok := s.SetLicense(license); !ok {
+	if ok := s.SetLicense(&license); !ok {
 		return nil, model.NewAppError("addLicense", model.ExpiredLicenseError, nil, "", http.StatusBadRequest)
 	}

@@ -165,7 +169,7 @@ func (s *Server) SaveLicense(licenseBytes []byte) (*model.License, *model.AppErr
 		}
 	}

-	return license, nil
+	return &license, nil
 }

 func (s *Server) SetLicense(license *model.License) bool {
@@ -196,8 +200,12 @@ func (s *Server) SetLicense(license *model.License) bool {

 func (s *Server) ValidateAndSetLicenseBytes(b []byte) bool {
 	if success, licenseStr := utils.LicenseValidator.ValidateLicense(b); success {
-		license := model.LicenseFromJson(strings.NewReader(licenseStr))
-		s.SetLicense(license)
+		var license model.License
+		if jsonErr := json.Unmarshal([]byte(licenseStr), &license); jsonErr != nil {
+			mlog.Warn("Failed to decode license from JSON", mlog.Err(jsonErr))
+			return false
+		}
+		s.SetLicense(&license)
 		return true
 	}

@@ -254,12 +262,17 @@ func (s *Server) GetSanitizedClientLicense() map[string]string {

 // RequestTrialLicense request a trial license from the mattermost official license server
 func (s *Server) RequestTrialLicense(trialRequest *model.TrialLicenseRequest) *model.AppError {
-	resp, err := http.Post(RequestTrialURL, "application/json", bytes.NewBuffer([]byte(trialRequest.ToJson())))
+	trialRequestJSON, jsonErr := json.Marshal(trialRequest)
+	if jsonErr != nil {
+		return model.NewAppError("RequestTrialLicense", "api.unmarshal_error", nil, jsonErr.Error(), http.StatusInternalServerError)
+	}
+
+	resp, err := http.Post(RequestTrialURL, "application/json", bytes.NewBuffer(trialRequestJSON))
 	if err != nil {
 		return model.NewAppError("RequestTrialLicense", "api.license.request_trial_license.app_error", nil, err.Error(), http.StatusBadRequest)
 	}
 	defer resp.Body.Close()
-	licenseResponse := model.MapFromJson(resp.Body)
+	licenseResponse := model.MapFromJSON(resp.Body)

 	if _, ok := licenseResponse["license"]; !ok {
 		return model.NewAppError("RequestTrialLicense", "api.license.request_trial_license.app_error", nil, licenseResponse["message"], http.StatusBadRequest)
--- a/app/notification.go
+++ b/app/notification.go
@@ -5,6 +5,7 @@ package app

 import (
 	"context"
+	"encoding/json"
 	"net/http"
 	"sort"
 	"strings"
@@ -524,7 +525,11 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 	message := model.NewWebSocketEvent(model.WebsocketEventPosted, "", post.ChannelId, "", nil)

 	// Note that PreparePostForClient should've already been called by this point
-	message.Add("post", post.ToJson())
+	postJSON, jsonErr := post.ToJSON()
+	if jsonErr != nil {
+		return nil, errors.Wrapf(jsonErr, "failed to encode post to JSON")
+	}
+	message.Add("post", postJSON)

 	message.Add("channel_type", channel.Type)
 	message.Add("channel_display_name", notification.GetChannelName(model.ShowUsername, ""))
@@ -552,11 +557,11 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 	}

 	if len(mentionedUsersList) != 0 {
-		message.Add("mentions", model.ArrayToJson(mentionedUsersList))
+		message.Add("mentions", model.ArrayToJSON(mentionedUsersList))
 	}

 	if len(notificationsForCRT.Desktop) != 0 {
-		message.Add("followers", model.ArrayToJson(notificationsForCRT.Desktop))
+		message.Add("followers", model.ArrayToJSON(notificationsForCRT.Desktop))
 	}

 	published, err := a.publishWebsocketEventForPermalinkPost(post, message)
@@ -607,7 +612,12 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 						}
 					}

-					message.Add("thread", userThread.ToJson())
+					payload, jsonErr := json.Marshal(userThread)
+					if jsonErr != nil {
+						mlog.Warn("Failed to encode thread to JSON")
+					}
+					message.Add("thread", string(payload))
+
 					a.Publish(message)
 				}
 			}
--- a/app/notification_push.go
+++ b/app/notification_push.go
@@ -4,6 +4,8 @@
 package app

 import (
+	"bytes"
+	"encoding/json"
 	"io"
 	"io/ioutil"
 	"net/http"
@@ -367,8 +369,13 @@ func (a *App) sendToPushProxy(msg *model.PushNotification, session *model.Sessio
 		mlog.String("status", model.PushSendPrepare),
 	)

+	msgJSON, jsonErr := json.Marshal(msg)
+	if jsonErr != nil {
+		return errors.Wrap(jsonErr, "failed to encode to JSON")
+	}
+
 	url := strings.TrimRight(*a.Config().EmailSettings.PushNotificationServer, "/") + model.APIURLSuffixV1 + "/send_push"
-	request, err := http.NewRequest("POST", url, strings.NewReader(msg.ToJson()))
+	request, err := http.NewRequest("POST", url, bytes.NewReader(msgJSON))
 	if err != nil {
 		return err
 	}
@@ -379,7 +386,10 @@ func (a *App) sendToPushProxy(msg *model.PushNotification, session *model.Sessio
 	}
 	defer resp.Body.Close()

-	pushResponse := model.PushResponseFromJson(resp.Body)
+	var pushResponse model.PushResponse
+	if jsonErr := json.NewDecoder(resp.Body).Decode(&pushResponse); jsonErr != nil {
+		return errors.Wrap(jsonErr, "failed to decode from JSON")
+	}

 	switch pushResponse[model.PushStatus] {
 	case model.PushStatusRemove:
@@ -405,10 +415,15 @@ func (a *App) SendAckToPushProxy(ack *model.PushNotificationAck) error {
 		mlog.String("status", model.PushReceived),
 	)

+	ackJSON, jsonErr := json.Marshal(ack)
+	if jsonErr != nil {
+		return errors.Wrap(jsonErr, "failed to encode to JSON")
+	}
+
 	request, err := http.NewRequest(
 		"POST",
 		strings.TrimRight(*a.Config().EmailSettings.PushNotificationServer, "/")+model.APIURLSuffixV1+"/ack",
-		strings.NewReader(ack.ToJson()),
+		bytes.NewReader(ackJSON),
 	)

 	if err != nil {
--- a/app/notification_push_test.go
+++ b/app/notification_push_test.go
@@ -4,6 +4,7 @@
 package app

 import (
+	"encoding/json"
 	"fmt"
 	"net/http"
 	"net/http/httptest"
@@ -1024,18 +1025,19 @@ func (h *testPushNotificationHandler) handleReq(w http.ResponseWriter, r *http.R
 		// Don't do any checking if it's a benchmark
 		if _, ok := h.t.(*testing.B); ok {
 			resp := model.NewOkPushResponse()
-			fmt.Fprintln(w, (&resp).ToJson())
+			jsonData, _ := json.Marshal(&resp)
+			fmt.Fprintln(w, jsonData)
 			return
 		}

-		var notification *model.PushNotification
-		var notificationAck *model.PushNotificationAck
+		var notification model.PushNotification
+		var notificationAck model.PushNotificationAck
 		var err error
 		if r.URL.Path == "/api/v1/send_push" {
-			notification, err = model.PushNotificationFromJson(r.Body)
-			if err != nil {
+			if err = json.NewDecoder(r.Body).Decode(&notification); err != nil {
 				resp := model.NewErrorPushResponse("fail")
-				fmt.Fprintln(w, (&resp).ToJson())
+				jsonData, _ := json.Marshal(&resp)
+				fmt.Fprintln(w, jsonData)
 				return
 			}
 			// We verify that messages are being sent in order per-device.
@@ -1047,10 +1049,10 @@ func (h *testPushNotificationHandler) handleReq(w http.ResponseWriter, r *http.R
 				defer h.serialUserMap.Delete(notification.DeviceId)
 			}
 		} else {
-			notificationAck, err = model.PushNotificationAckFromJson(r.Body)
-			if err != nil {
+			if err = json.NewDecoder(r.Body).Decode(&notificationAck); err != nil {
 				resp := model.NewErrorPushResponse("fail")
-				fmt.Fprintln(w, (&resp).ToJson())
+				jsonData, _ := json.Marshal(&resp)
+				fmt.Fprintln(w, jsonData)
 				return
 			}
 		}
@@ -1061,9 +1063,9 @@ func (h *testPushNotificationHandler) handleReq(w http.ResponseWriter, r *http.R
 		// Little bit of duplicate condition check so that we can check the in-order property
 		// first.
 		if r.URL.Path == "/api/v1/send_push" {
-			h._notifications = append(h._notifications, notification)
+			h._notifications = append(h._notifications, &notification)
 		} else {
-			h._notificationAcks = append(h._notificationAcks, notificationAck)
+			h._notificationAcks = append(h._notificationAcks, &notificationAck)
 		}

 		var resp model.PushResponse
@@ -1077,7 +1079,8 @@ func (h *testPushNotificationHandler) handleReq(w http.ResponseWriter, r *http.R
 				resp = model.NewRemovePushResponse()
 			}
 		}
-		fmt.Fprintln(w, (&resp).ToJson())
+		jsonData, _ := json.Marshal(&resp)
+		fmt.Fprintln(w, jsonData)
 	}
 }

--- a/app/oauth.go
+++ b/app/oauth.go
@@ -582,7 +582,7 @@ func (a *App) LoginByOAuth(c *request.Context, service string, userData io.Reade
 			map[string]interface{}{"Service": service}, "", http.StatusBadRequest)
 	}

-	authUser, err1 := provider.GetUserFromJson(bytes.NewReader(buf.Bytes()), tokenUser)
+	authUser, err1 := provider.GetUserFromJSON(bytes.NewReader(buf.Bytes()), tokenUser)
 	if err1 != nil {
 		return nil, model.NewAppError("LoginByOAuth", "api.user.login_by_oauth.parse.app_error",
 			map[string]interface{}{"Service": service}, err1.Error(), http.StatusBadRequest)
@@ -633,7 +633,7 @@ func (a *App) CompleteSwitchWithOAuth(service string, userData io.Reader, email
 		return nil, model.NewAppError("CompleteSwitchWithOAuth", "api.user.complete_switch_with_oauth.blank_email.app_error", nil, "", http.StatusBadRequest)
 	}

-	ssoUser, err1 := provider.GetUserFromJson(userData, tokenUser)
+	ssoUser, err1 := provider.GetUserFromJSON(userData, tokenUser)
 	if err1 != nil {
 		return nil, model.NewAppError("CompleteSwitchWithOAuth", "api.user.complete_switch_with_oauth.parse.app_error",
 			map[string]interface{}{"Service": service}, err1.Error(), http.StatusBadRequest)
@@ -744,7 +744,7 @@ func (a *App) GetAuthorizationCode(w http.ResponseWriter, r *http.Request, servi
 	}

 	props["token"] = stateToken.Token
-	state := b64.StdEncoding.EncodeToString([]byte(model.MapToJson(props)))
+	state := b64.StdEncoding.EncodeToString([]byte(model.MapToJSON(props)))

 	siteURL := a.GetSiteURL()
 	if strings.TrimSpace(siteURL) == "" {
@@ -783,7 +783,7 @@ func (a *App) AuthorizeOAuthUser(w http.ResponseWriter, r *http.Request, service
 	}

 	stateStr := string(b)
-	stateProps := model.MapFromJson(strings.NewReader(stateStr))
+	stateProps := model.MapFromJSON(strings.NewReader(stateStr))

 	expectedToken, appErr := a.GetOAuthStateToken(stateProps["token"])
 	if appErr != nil {
--- a/app/oauth_test.go
+++ b/app/oauth_test.go
@@ -152,7 +152,7 @@ func TestAuthorizeOAuthUser(t *testing.T) {
 	}

 	makeState := func(token *model.Token) string {
-		return base64.StdEncoding.EncodeToString([]byte(model.MapToJson(map[string]string{
+		return base64.StdEncoding.EncodeToString([]byte(model.MapToJSON(map[string]string{
 			"token": token.Token,
 		})))
 	}
@@ -199,7 +199,7 @@ func TestAuthorizeOAuthUser(t *testing.T) {
 		th := setup(t, true, true, true, "")
 		defer th.TearDown()

-		state := base64.StdEncoding.EncodeToString([]byte(model.MapToJson(map[string]string{
+		state := base64.StdEncoding.EncodeToString([]byte(model.MapToJSON(map[string]string{
 			"token": model.NewId(),
 		})))

@@ -235,7 +235,7 @@ func TestAuthorizeOAuthUser(t *testing.T) {
 		token, err := th.App.CreateOAuthStateToken(generateOAuthStateTokenExtra(email, action, cookie))
 		require.Nil(t, err)

-		state := base64.StdEncoding.EncodeToString([]byte(model.MapToJson(map[string]string{
+		state := base64.StdEncoding.EncodeToString([]byte(model.MapToJSON(map[string]string{
 			"action": action,
 			"email":  email,
 			"token":  token.Token,
@@ -489,7 +489,7 @@ func TestAuthorizeOAuthUser(t *testing.T) {
 					"team_id": model.NewId(),
 					"token":   makeToken(th, cookie).Token,
 				}
-				state := base64.StdEncoding.EncodeToString([]byte(model.MapToJson(stateProps)))
+				state := base64.StdEncoding.EncodeToString([]byte(model.MapToJSON(stateProps)))

 				recorder := httptest.ResponseRecorder{}
 				body, receivedTeamId, receivedStateProps, _, err := th.App.AuthorizeOAuthUser(&recorder, request, model.ServiceGitlab, "", state, "")
--- a/app/plugin_api_tests/manual.test_http_upgrade_websocket_plugin/main.go
+++ b/app/plugin_api_tests/manual.test_http_upgrade_websocket_plugin/main.go
@@ -4,7 +4,7 @@
 package main

 import (
-	"bytes"
+	"encoding/json"
 	"net/http"

 	"github.com/gorilla/websocket"
@@ -32,9 +32,17 @@ func (p *Plugin) ServeHTTP(_ *plugin.Context, w http.ResponseWriter, r *http.Req
 		if err != nil {
 			break
 		}
-		req := model.WebSocketRequestFromJson(bytes.NewReader(msg))
+		var req model.WebSocketRequest
+		err = json.Unmarshal(msg, &req)
+		if err != nil {
+			break
+		}
 		resp := model.NewWebSocketResponse("OK", req.Seq, map[string]interface{}{"action": req.Action, "value": req.Data["value"]})
-		if err = ws.WriteMessage(mt, resp.ToJson()); err != nil {
+		respJSON, err := resp.ToJSON()
+		if err != nil {
+			break
+		}
+		if err = ws.WriteMessage(mt, respJSON); err != nil {
 			break
 		}
 	}
--- a/app/plugin_install_test.go
+++ b/app/plugin_install_test.go
@@ -7,6 +7,7 @@ import (
 	"archive/tar"
 	"bytes"
 	"compress/gzip"
+	"encoding/json"
 	"io"
 	"os"
 	"path/filepath"
@@ -99,8 +100,10 @@ func TestInstallPluginLocally(t *testing.T) {
 			Id:      id,
 			Version: version,
 		}
+		manifestJSON, jsonErr := json.Marshal(manifest)
+		require.NoError(t, jsonErr)
 		reader := makeInMemoryGzipTarFile(t, []testFile{
-			{"plugin.json", manifest.ToJson()},
+			{"plugin.json", string(manifestJSON)},
 		})

 		actualManifest, appError := th.App.installPluginLocally(reader, nil, installationStrategy)
--- a/app/plugin_requests.go
+++ b/app/plugin_requests.go
@@ -27,7 +27,7 @@ func (s *Server) ServePluginRequest(w http.ResponseWriter, r *http.Request) {
 		s.Log.Error(err.Error())
 		w.WriteHeader(err.StatusCode)
 		w.Header().Set("Content-Type", "application/json")
-		w.Write([]byte(err.ToJson()))
+		w.Write([]byte(err.ToJSON()))
 		return
 	}

@@ -52,7 +52,7 @@ func (a *App) ServeInterPluginRequest(w http.ResponseWriter, r *http.Request, so
 		a.Log().Error(err.Error())
 		w.WriteHeader(err.StatusCode)
 		w.Header().Set("Content-Type", "application/json")
-		w.Write([]byte(err.ToJson()))
+		w.Write([]byte(err.ToJSON()))
 		return
 	}

--- a/app/post.go
+++ b/app/post.go
@@ -522,7 +522,12 @@ func (a *App) SendEphemeralPost(userID string, post *model.Post) *model.Post {
 	message := model.NewWebSocketEvent(model.WebsocketEventEphemeralMessage, "", post.ChannelId, userID, nil)
 	post = a.PreparePostForClient(post, true, false)
 	post = model.AddPostActionCookies(post, a.PostActionCookieSecret())
-	message.Add("post", post.ToJson())
+
+	postJSON, jsonErr := post.ToJSON()
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode post to JSON", mlog.Err(jsonErr))
+	}
+	message.Add("post", postJSON)
 	a.Publish(message)

 	return post
@@ -540,7 +545,11 @@ func (a *App) UpdateEphemeralPost(userID string, post *model.Post) *model.Post {
 	message := model.NewWebSocketEvent(model.WebsocketEventPostEdited, "", post.ChannelId, userID, nil)
 	post = a.PreparePostForClient(post, true, false)
 	post = model.AddPostActionCookies(post, a.PostActionCookieSecret())
-	message.Add("post", post.ToJson())
+	postJSON, jsonErr := post.ToJSON()
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode post to JSON", mlog.Err(jsonErr))
+	}
+	message.Add("post", postJSON)
 	a.Publish(message)

 	return post
@@ -556,7 +565,11 @@ func (a *App) DeleteEphemeralPost(userID, postID string) {
 	}

 	message := model.NewWebSocketEvent(model.WebsocketEventPostDeleted, "", "", userID, nil)
-	message.Add("post", post.ToJson())
+	postJSON, jsonErr := post.ToJSON()
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode post to JSON", mlog.Err(jsonErr))
+	}
+	message.Add("post", postJSON)
 	a.Publish(message)
 }

@@ -684,7 +697,11 @@ func (a *App) UpdatePost(c *request.Context, post *model.Post, safeUpdate bool)
 	}

 	message := model.NewWebSocketEvent(model.WebsocketEventPostEdited, "", rpost.ChannelId, "", nil)
-	message.Add("post", rpost.ToJson())
+	postJSON, jsonErr := rpost.ToJSON()
+	if jsonErr != nil {
+		return nil, model.NewAppError("UpdatePost", "app.post.marshal.app_error", nil, jsonErr.Error(), http.StatusInternalServerError)
+	}
+	message.Add("post", postJSON)

 	published, err := a.publishWebsocketEventForPermalinkPost(rpost, message)
 	if err != nil {
@@ -744,7 +761,12 @@ func (a *App) publishWebsocketEventForPermalinkPost(post *model.Post, message *m
 		broadcastCopy := messageCopy.GetBroadcast()
 		broadcastCopy.UserId = cm.UserId
 		messageCopy.SetBroadcast(broadcastCopy)
-		messageCopy.Add("post", postForUser.ToJson())
+
+		postJSON, jsonErr := postForUser.ToJSON()
+		if jsonErr != nil {
+			mlog.Warn("Failed to encode post to JSON", mlog.Err(jsonErr))
+		}
+		messageCopy.Add("post", postJSON)
 		a.Publish(messageCopy)
 	}

--- a/app/preference.go
+++ b/app/preference.go
@@ -4,10 +4,12 @@
 package app

 import (
+	"encoding/json"
 	"errors"
 	"net/http"

 	"github.com/mattermost/mattermost-server/v6/model"
+	"github.com/mattermost/mattermost-server/v6/shared/mlog"
 )

 func (a *App) GetPreferencesForUser(userID string) (model.Preferences, *model.AppError) {
@@ -65,7 +67,11 @@ func (a *App) UpdatePreferences(userID string, preferences model.Preferences) *m
 	a.Publish(message)

 	message = model.NewWebSocketEvent(model.WebsocketEventPreferencesChanged, "", "", userID, nil)
-	message.Add("preferences", preferences.ToJson())
+	prefsJSON, jsonErr := json.Marshal(preferences)
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode to JSON", mlog.Err(jsonErr))
+	}
+	message.Add("preferences", string(prefsJSON))
 	a.Publish(message)

 	return nil
@@ -95,7 +101,11 @@ func (a *App) DeletePreferences(userID string, preferences model.Preferences) *m
 	a.Publish(message)

 	message = model.NewWebSocketEvent(model.WebsocketEventPreferencesDeleted, "", "", userID, nil)
-	message.Add("preferences", preferences.ToJson())
+	prefsJSON, jsonErr := json.Marshal(preferences)
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode to JSON", mlog.Err(jsonErr))
+	}
+	message.Add("preferences", string(prefsJSON))
 	a.Publish(message)

 	return nil
--- a/app/reaction.go
+++ b/app/reaction.go
@@ -4,12 +4,14 @@
 package app

 import (
+	"encoding/json"
 	"errors"
 	"net/http"

 	"github.com/mattermost/mattermost-server/v6/app/request"
 	"github.com/mattermost/mattermost-server/v6/model"
 	"github.com/mattermost/mattermost-server/v6/plugin"
+	"github.com/mattermost/mattermost-server/v6/shared/mlog"
 )

 func (a *App) SaveReactionForPost(c *request.Context, reaction *model.Reaction) (*model.Reaction, *model.AppError) {
@@ -159,6 +161,10 @@ func (a *App) DeleteReactionForPost(c *request.Context, reaction *model.Reaction
 func (a *App) sendReactionEvent(event string, reaction *model.Reaction, post *model.Post) {
 	// send out that a reaction has been added/removed
 	message := model.NewWebSocketEvent(event, "", post.ChannelId, "", nil)
-	message.Add("reaction", reaction.ToJson())
+	reactionJSON, jsonErr := json.Marshal(reaction)
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode reaction to JSON")
+	}
+	message.Add("reaction", string(reactionJSON))
 	a.Publish(message)
 }
--- a/app/role.go
+++ b/app/role.go
@@ -5,12 +5,14 @@ package app

 import (
 	"context"
+	"encoding/json"
 	"errors"
 	"net/http"
 	"reflect"
 	"strings"

 	"github.com/mattermost/mattermost-server/v6/model"
+	"github.com/mattermost/mattermost-server/v6/shared/mlog"
 	"github.com/mattermost/mattermost-server/v6/store"
 	"github.com/mattermost/mattermost-server/v6/utils"
 )
@@ -240,7 +242,11 @@ func (a *App) CheckRolesExist(roleNames []string) *model.AppError {

 func (a *App) sendUpdatedRoleEvent(role *model.Role) {
 	message := model.NewWebSocketEvent(model.WebsocketEventRoleUpdated, "", "", "", nil)
-	message.Add("role", role.ToJson())
+	roleJSON, jsonErr := json.Marshal(role)
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode role to JSON", mlog.Err(jsonErr))
+	}
+	message.Add("role", string(roleJSON))

 	a.Srv().Go(func() {
 		a.Publish(message)
--- a/app/security_update_check.go
+++ b/app/security_update_check.go
@@ -4,6 +4,7 @@
 package app

 import (
+	"encoding/json"
 	"io/ioutil"
 	"net/http"
 	"net/url"
@@ -88,7 +89,11 @@ func (s *Server) DoSecurityUpdateCheck() {

 		defer res.Body.Close()

-		bulletins := model.SecurityBulletinsFromJson(res.Body)
+		var bulletins model.SecurityBulletins
+		if jsonErr := json.NewDecoder(res.Body).Decode(&bulletins); jsonErr != nil {
+			mlog.Error("Failed to decode JSON", mlog.Err(jsonErr))
+			return
+		}

 		for _, bulletin := range bulletins {
 			if bulletin.AppliesToVersion == model.CurrentVersion {
--- a/app/slashcommands/command_expand_collapse.go
+++ b/app/slashcommands/command_expand_collapse.go
@@ -4,12 +4,14 @@
 package slashcommands

 import (
+	"encoding/json"
 	"strconv"

 	"github.com/mattermost/mattermost-server/v6/app"
 	"github.com/mattermost/mattermost-server/v6/app/request"
 	"github.com/mattermost/mattermost-server/v6/model"
 	"github.com/mattermost/mattermost-server/v6/shared/i18n"
+	"github.com/mattermost/mattermost-server/v6/shared/mlog"
 )

 type ExpandProvider struct {
@@ -75,7 +77,12 @@ func setCollapsePreference(a *app.App, args *model.CommandArgs, isCollapse bool)
 	}

 	socketMessage := model.NewWebSocketEvent(model.WebsocketEventPreferenceChanged, "", "", args.UserId, nil)
-	socketMessage.Add("preference", pref.ToJson())
+
+	prefJSON, jsonErr := json.Marshal(pref)
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode to JSON", mlog.Err(jsonErr))
+	}
+	socketMessage.Add("preference", string(prefJSON))
 	a.Publish(socketMessage)

 	var rmsg string
--- a/app/slashcommands/command_loadtest.go
+++ b/app/slashcommands/command_loadtest.go
@@ -4,6 +4,7 @@
 package slashcommands

 import (
+	"encoding/json"
 	"io"
 	"io/ioutil"
 	"net/http"
@@ -542,8 +543,8 @@ func (*LoadTestProvider) JsonCommand(a *app.App, c *request.Context, args *model
 		r.Body.Close()
 	}()

-	post := model.PostFromJson(r.Body)
-	if post == nil {
+	var post model.Post
+	if jsonErr := json.NewDecoder(r.Body).Decode(&post); jsonErr != nil {
 		return &model.CommandResponse{Text: "Unable to decode post", ResponseType: model.CommandResponseTypeEphemeral}, errors.Errorf("could not decode post from json")
 	}
 	post.ChannelId = args.ChannelId
@@ -552,7 +553,7 @@ func (*LoadTestProvider) JsonCommand(a *app.App, c *request.Context, args *model
 		post.Message = message
 	}

-	if _, err := a.CreatePostMissingChannel(c, post, false); err != nil {
+	if _, err := a.CreatePostMissingChannel(c, &post, false); err != nil {
 		return &model.CommandResponse{Text: "Unable to create post", ResponseType: model.CommandResponseTypeEphemeral}, err
 	}

--- a/app/slashcommands/command_share_test.go
+++ b/app/slashcommands/command_share_test.go
@@ -50,8 +50,8 @@ func TestShareProviderDoCommand(t *testing.T) {
 		require.Equal(t, "##### "+args.T("api.command_share.channel_shared"), response.Text)

 		channelConvertedMessages := testCluster.SelectMessages(func(msg *model.ClusterMessage) bool {
-			event := model.WebSocketEventFromJson(bytes.NewReader(msg.Data))
-			return event != nil && event.EventType() == model.WebsocketEventChannelConverted
+			event, err := model.WebSocketEventFromJSON(bytes.NewReader(msg.Data))
+			return err == nil && event.EventType() == model.WebsocketEventChannelConverted
 		})
 		assert.Len(t, channelConvertedMessages, 1)
 	})
@@ -85,8 +85,8 @@ func TestShareProviderDoCommand(t *testing.T) {
 		require.Equal(t, "##### "+args.T("api.command_share.shared_channel_unavailable"), response.Text)

 		channelConvertedMessages := testCluster.SelectMessages(func(msg *model.ClusterMessage) bool {
-			event := model.WebSocketEventFromJson(bytes.NewReader(msg.Data))
-			return event != nil && event.EventType() == model.WebsocketEventChannelConverted
+			event, err := model.WebSocketEventFromJSON(bytes.NewReader(msg.Data))
+			return err == nil && event.EventType() == model.WebsocketEventChannelConverted
 		})
 		require.Len(t, channelConvertedMessages, 1)
 	})
--- a/app/status.go
+++ b/app/status.go
@@ -4,9 +4,9 @@
 package app

 import (
+	"encoding/json"
 	"errors"
 	"net/http"
-	"strings"

 	"github.com/mattermost/mattermost-server/v6/model"
 	"github.com/mattermost/mattermost-server/v6/shared/mlog"
@@ -21,10 +21,14 @@ func (a *App) AddStatusCache(status *model.Status) {
 	a.AddStatusCacheSkipClusterSend(status)

 	if a.Cluster() != nil {
+		statusJSON, jsonErr := json.Marshal(status)
+		if jsonErr != nil {
+			mlog.Warn("Failed to encode status to JSON")
+		}
 		msg := &model.ClusterMessage{
 			Event:    model.ClusterEventUpdateStatus,
 			SendType: model.ClusterSendBestEffort,
-			Data:     []byte(status.ToClusterJson()),
+			Data:     statusJSON,
 		}
 		a.Cluster().SendClusterMessage(msg)
 	}
@@ -443,15 +447,22 @@ func (a *App) addRecentCustomStatus(userID string, status *model.CustomStatus) *
 	if err != nil || pref.Value == "" {
 		newRCS = model.RecentCustomStatuses{*status}
 	} else {
-		existingRCS := model.RecentCustomStatusesFromJson(strings.NewReader(pref.Value))
+		var existingRCS model.RecentCustomStatuses
+		if jsonErr := json.Unmarshal([]byte(pref.Value), &existingRCS); jsonErr != nil {
+			return model.NewAppError("addRecentCustomStatus", "api.unmarshal_error", nil, jsonErr.Error(), http.StatusBadRequest)
+		}
 		newRCS = existingRCS.Add(status)
 	}

+	newRCSJSON, jsonErr := json.Marshal(newRCS)
+	if jsonErr != nil {
+		return model.NewAppError("addRecentCustomStatus", "api.marshal_error", nil, jsonErr.Error(), http.StatusBadRequest)
+	}
 	pref = &model.Preference{
 		UserId:   userID,
 		Category: model.PreferenceCategoryCustomStatus,
 		Name:     model.PreferenceNameRecentCustomStatuses,
-		Value:    newRCS.ToJson(),
+		Value:    string(newRCSJSON),
 	}
 	if err := a.UpdatePreferences(userID, model.Preferences{*pref}); err != nil {
 		return err
@@ -470,14 +481,25 @@ func (a *App) RemoveRecentCustomStatus(userID string, status *model.CustomStatus
 		return model.NewAppError("RemoveRecentCustomStatus", "api.custom_status.recent_custom_statuses.delete.app_error", nil, "", http.StatusBadRequest)
 	}

-	existingRCS := model.RecentCustomStatusesFromJson(strings.NewReader(pref.Value))
-	if !existingRCS.Contains(status) {
+	var existingRCS model.RecentCustomStatuses
+	if jsonErr := json.Unmarshal([]byte(pref.Value), &existingRCS); jsonErr != nil {
+		return model.NewAppError("RemoveRecentCustomStatus", "api.unmarshal_error", nil, jsonErr.Error(), http.StatusBadRequest)
+	}
+
+	if ok, err := existingRCS.Contains(status); !ok || err != nil {
 		return model.NewAppError("RemoveRecentCustomStatus", "api.custom_status.recent_custom_statuses.delete.app_error", nil, "", http.StatusBadRequest)
 	}

-	newRCS := existingRCS.Remove(status)
-	pref.Value = newRCS.ToJson()
+	newRCS, removeErr := existingRCS.Remove(status)
+	if removeErr != nil {
+		return model.NewAppError("RemoveRecentCustomStatus", "api.custom_status.recent_custom_statuses.delete.app_error", nil, removeErr.Error(), http.StatusBadRequest)
+	}

+	newRCSJSON, jsonErr := json.Marshal(newRCS)
+	if jsonErr != nil {
+		return model.NewAppError("RemoveRecentCustomStatus", "api.marshal_error", nil, jsonErr.Error(), http.StatusBadRequest)
+	}
+	pref.Value = string(newRCSJSON)
 	if err := a.UpdatePreferences(userID, model.Preferences{*pref}); err != nil {
 		return err
 	}
--- a/app/team.go
+++ b/app/team.go
@@ -6,6 +6,7 @@ package app
 import (
 	"bytes"
 	"context"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"image"
@@ -337,7 +338,11 @@ func (a *App) sendTeamEvent(team *model.Team, event string) {
 		teamID = team.Id
 	}
 	message := model.NewWebSocketEvent(event, teamID, "", "", nil)
-	message.Add("team", sanitizedTeam.ToJson())
+	teamJSON, jsonErr := json.Marshal(team)
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode team to JSON", mlog.Err(jsonErr))
+	}
+	message.Add("team", string(teamJSON))
 	a.Publish(message)
 }

@@ -479,7 +484,11 @@ func (a *App) UpdateTeamMemberSchemeRoles(teamID string, userID string, isScheme

 func (a *App) sendUpdatedMemberRoleEvent(userID string, member *model.TeamMember) {
 	message := model.NewWebSocketEvent(model.WebsocketEventMemberroleUpdated, "", "", userID, nil)
-	message.Add("member", member.ToJson())
+	tmJSON, jsonErr := json.Marshal(member)
+	if jsonErr != nil {
+		mlog.Warn("Failed to encode team member to JSON", mlog.Err(jsonErr))
+	}
+	message.Add("member", string(tmJSON))
 	a.Publish(message)
 }

@@ -563,7 +572,7 @@ func (a *App) AddUserToTeamByToken(c *request.Context, userID string, tokenID st
 		return nil, nil, model.NewAppError("AddUserToTeamByToken", "api.user.create_user.signup_link_expired.app_error", nil, "", http.StatusBadRequest)
 	}

-	tokenData := model.MapFromJson(strings.NewReader(token.Extra))
+	tokenData := model.MapFromJSON(strings.NewReader(token.Extra))

 	tchan := make(chan store.StoreResult, 1)
 	go func() {
@@ -1862,7 +1871,7 @@ func (a *App) GetTeamIdFromQuery(query url.Values) (string, *model.AppError) {
 			return "", model.NewAppError("GetTeamIdFromQuery", "api.oauth.singup_with_oauth.expired_link.app_error", nil, "", http.StatusBadRequest)
 		}

-		tokenData := model.MapFromJson(strings.NewReader(token.Extra))
+		tokenData := model.MapFromJSON(strings.NewReader(token.Extra))

 		return tokenData["teamId"], nil
 	}
@@ -2027,7 +2036,11 @@ func (a *App) ClearTeamMembersCache(teamID string) {
 			a.ClearSessionCacheForUser(teamMember.UserId)

 			message := model.NewWebSocketEvent(model.WebsocketEventMemberroleUpdated, "", "", teamMember.UserId, nil)
-			message.Add("member", teamMember.ToJson())
+			tmJSON, jsonErr := json.Marshal(teamMember)
+			if jsonErr != nil {
+				mlog.Warn("Failed to encode team member to JSON", mlog.Err(jsonErr))
+			}
+			message.Add("member", string(tmJSON))
 			a.Publish(message)
 		}

--- a/app/team_test.go
+++ b/app/team_test.go
@@ -202,7 +202,7 @@ func TestAddUserToTeamByToken(t *testing.T) {
 	t.Run("invalid token type", func(t *testing.T) {
 		token := model.NewToken(
 			TokenTypeVerifyEmail,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id}),
 		)

 		require.NoError(t, th.App.Srv().Store.Token().Save(token))
@@ -215,7 +215,7 @@ func TestAddUserToTeamByToken(t *testing.T) {
 	t.Run("expired token", func(t *testing.T) {
 		token := model.NewToken(
 			TokenTypeTeamInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id}),
 		)

 		token.CreateAt = model.GetMillis() - InvitationExpiryTime - 1
@@ -229,7 +229,7 @@ func TestAddUserToTeamByToken(t *testing.T) {
 	t.Run("invalid team id", func(t *testing.T) {
 		token := model.NewToken(
 			TokenTypeTeamInvitation,
-			model.MapToJson(map[string]string{"teamId": model.NewId()}),
+			model.MapToJSON(map[string]string{"teamId": model.NewId()}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))
 		defer th.App.DeleteToken(token)
@@ -241,7 +241,7 @@ func TestAddUserToTeamByToken(t *testing.T) {
 	t.Run("invalid user id", func(t *testing.T) {
 		token := model.NewToken(
 			TokenTypeTeamInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))
 		defer th.App.DeleteToken(token)
@@ -253,7 +253,7 @@ func TestAddUserToTeamByToken(t *testing.T) {
 	t.Run("valid request", func(t *testing.T) {
 		token := model.NewToken(
 			TokenTypeTeamInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))
 		_, _, err := th.App.AddUserToTeamByToken(th.Context, ruser.Id, token.Token)
@@ -270,7 +270,7 @@ func TestAddUserToTeamByToken(t *testing.T) {
 	t.Run("invalid add a guest using a regular invite", func(t *testing.T) {
 		token := model.NewToken(
 			TokenTypeTeamInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))
 		_, _, err := th.App.AddUserToTeamByToken(th.Context, rguest.Id, token.Token)
@@ -280,7 +280,7 @@ func TestAddUserToTeamByToken(t *testing.T) {
 	t.Run("invalid add a regular user using a guest invite", func(t *testing.T) {
 		token := model.NewToken(
 			TokenTypeGuestInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id, "channels": th.BasicChannel.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id, "channels": th.BasicChannel.Id}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))
 		_, _, err := th.App.AddUserToTeamByToken(th.Context, ruser.Id, token.Token)
@@ -295,7 +295,7 @@ func TestAddUserToTeamByToken(t *testing.T) {
 		th.App.UpdateConfig(func(cfg *model.Config) { *cfg.GuestAccountsSettings.RestrictCreationToDomains = "restricted.com" })
 		token := model.NewToken(
 			TokenTypeGuestInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id, "channels": th.BasicChannel.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id, "channels": th.BasicChannel.Id}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))
 		_, _, err := th.App.AddUserToTeamByToken(th.Context, rguest.Id, token.Token)
@@ -311,7 +311,7 @@ func TestAddUserToTeamByToken(t *testing.T) {
 		th.App.UpdateConfig(func(cfg *model.Config) { *cfg.GuestAccountsSettings.RestrictCreationToDomains = "restricted.com" })
 		token := model.NewToken(
 			TokenTypeGuestInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id, "channels": th.BasicChannel.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id, "channels": th.BasicChannel.Id}),
 		)
 		guestEmail := rguest.Email
 		rguest.Email = "test@restricted.com"
@@ -337,7 +337,7 @@ func TestAddUserToTeamByToken(t *testing.T) {
 		th.App.UpdateConfig(func(cfg *model.Config) { *cfg.TeamSettings.RestrictCreationToDomains = "restricted.com" })
 		token := model.NewToken(
 			TokenTypeGuestInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id, "channels": th.BasicChannel.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id, "channels": th.BasicChannel.Id}),
 		)
 		_, err = th.App.Srv().Store.User().Update(rguest, false)
 		require.NoError(t, err)
@@ -352,7 +352,7 @@ func TestAddUserToTeamByToken(t *testing.T) {
 	t.Run("valid request from guest invite", func(t *testing.T) {
 		token := model.NewToken(
 			TokenTypeGuestInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id, "channels": th.BasicChannel.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id, "channels": th.BasicChannel.Id}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))

@@ -375,7 +375,7 @@ func TestAddUserToTeamByToken(t *testing.T) {

 		token := model.NewToken(
 			TokenTypeTeamInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))

@@ -399,7 +399,7 @@ func TestAddUserToTeamByToken(t *testing.T) {

 		token := model.NewToken(
 			TokenTypeTeamInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))

@@ -414,7 +414,7 @@ func TestAddUserToTeamByToken(t *testing.T) {

 		token := model.NewToken(
 			TokenTypeTeamInvitation,
-			model.MapToJson(map[string]string{"teamId": team.Id}),
+			model.MapToJSON(map[string]string{"teamId": team.Id}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))

--- a/app/user.go
+++ b/app/user.go
@@ -54,7 +54,7 @@ func (a *App) CreateUserWithToken(c *request.Context, user *model.User, token *m
 		return nil, model.NewAppError("CreateUserWithToken", "api.user.create_user.signup_link_expired.app_error", nil, "", http.StatusBadRequest)
 	}

-	tokenData := model.MapFromJson(strings.NewReader(token.Extra))
+	tokenData := model.MapFromJSON(strings.NewReader(token.Extra))

 	team, nErr := a.Srv().Store.Team().Get(tokenData["teamId"])
 	if nErr != nil {
@@ -294,7 +294,7 @@ func (a *App) CreateOAuthUser(c *request.Context, service string, userData io.Re
 	if e != nil {
 		return nil, e
 	}
-	user, err1 := provider.GetUserFromJson(userData, tokenUser)
+	user, err1 := provider.GetUserFromJSON(userData, tokenUser)
 	if err1 != nil {
 		return nil, model.NewAppError("CreateOAuthUser", "api.user.create_oauth_user.create.app_error", map[string]interface{}{"Service": service}, err1.Error(), http.StatusInternalServerError)
 	}
@@ -1816,7 +1816,7 @@ func (a *App) AutocompleteUsersInTeam(teamID string, term string, options *model
 }

 func (a *App) UpdateOAuthUserAttrs(userData io.Reader, user *model.User, provider einterfaces.OAuthProvider, service string, tokenUser *model.User) *model.AppError {
-	oauthUser, err1 := provider.GetUserFromJson(userData, tokenUser)
+	oauthUser, err1 := provider.GetUserFromJSON(userData, tokenUser)
 	if err1 != nil {
 		return model.NewAppError("UpdateOAuthUserAttrs", "api.user.update_oauth_user_attrs.get_user.app_error", map[string]interface{}{"Service": service}, err1.Error(), http.StatusBadRequest)
 	}
@@ -2060,7 +2060,11 @@ func (a *App) PromoteGuestToUser(c *request.Context, user *model.User, requestor
 			a.invalidateCacheForChannelMembers(member.ChannelId)

 			evt := model.NewWebSocketEvent(model.WebsocketEventChannelMemberUpdated, "", "", user.Id, nil)
-			evt.Add("channelMember", member.ToJson())
+			memberJSON, jsonErr := json.Marshal(member)
+			if jsonErr != nil {
+				mlog.Warn("Failed to encode channel member to JSON", mlog.Err(jsonErr))
+			}
+			evt.Add("channelMember", string(memberJSON))
 			a.Publish(evt)
 		}
 	}
@@ -2101,7 +2105,11 @@ func (a *App) DemoteUserToGuest(user *model.User) *model.AppError {
 			a.invalidateCacheForChannelMembers(member.ChannelId)

 			evt := model.NewWebSocketEvent(model.WebsocketEventChannelMemberUpdated, "", "", user.Id, nil)
-			evt.Add("channelMember", member.ToJson())
+			memberJSON, jsonErr := json.Marshal(member)
+			if jsonErr != nil {
+				mlog.Warn("Failed to encode channel member to JSON", mlog.Err(jsonErr))
+			}
+			evt.Add("channelMember", string(memberJSON))
 			a.Publish(evt)
 		}
 	}
--- a/app/user_test.go
+++ b/app/user_test.go
@@ -38,9 +38,10 @@ func TestCreateOAuthUser(t *testing.T) {

 	t.Run("create user successfully", func(t *testing.T) {
 		glUser := oauthgitlab.GitLabUser{Id: 42, Username: "o" + model.NewId(), Email: model.NewId() + "@simulator.amazonses.com", Name: "Joram Wilander"}
-		json := glUser.ToJson()
+		js, jsonErr := json.Marshal(glUser)
+		require.NoError(t, jsonErr)

-		user, err := th.App.CreateOAuthUser(th.Context, model.UserAuthServiceGitlab, strings.NewReader(json), th.BasicTeam.Id, nil)
+		user, err := th.App.CreateOAuthUser(th.Context, model.UserAuthServiceGitlab, bytes.NewReader(js), th.BasicTeam.Id, nil)
 		require.Nil(t, err)

 		require.Equal(t, glUser.Username, user.Username, "usernames didn't match")
@@ -59,7 +60,7 @@ func TestCreateOAuthUser(t *testing.T) {
 		mockUser := &model.User{Id: "abcdef", AuthData: model.NewString("e7110007-64be-43d8-9840-4a7e9c26b710"), Email: dbUser.Email}
 		providerMock := &mocks.OAuthProvider{}
 		providerMock.On("IsSameUser", mock.Anything, mock.Anything).Return(true)
-		providerMock.On("GetUserFromJson", mock.Anything, mock.Anything).Return(mockUser, nil)
+		providerMock.On("GetUserFromJSON", mock.Anything, mock.Anything).Return(mockUser, nil)
 		einterfaces.RegisterOAuthProvider(model.ServiceOffice365, providerMock)

 		// Update user to be OAuth, formatting to match Office365 OAuth data
@@ -734,7 +735,7 @@ func TestCreateUserWithToken(t *testing.T) {
 	t.Run("invalid token type", func(t *testing.T) {
 		token := model.NewToken(
 			TokenTypeVerifyEmail,
-			model.MapToJson(map[string]string{"teamID": th.BasicTeam.Id, "email": user.Email}),
+			model.MapToJSON(map[string]string{"teamID": th.BasicTeam.Id, "email": user.Email}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))
 		defer th.App.DeleteToken(token)
@@ -745,7 +746,7 @@ func TestCreateUserWithToken(t *testing.T) {
 	t.Run("expired token", func(t *testing.T) {
 		token := model.NewToken(
 			TokenTypeTeamInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id, "email": user.Email}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id, "email": user.Email}),
 		)
 		token.CreateAt = model.GetMillis() - InvitationExpiryTime - 1
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))
@@ -757,7 +758,7 @@ func TestCreateUserWithToken(t *testing.T) {
 	t.Run("invalid team id", func(t *testing.T) {
 		token := model.NewToken(
 			TokenTypeTeamInvitation,
-			model.MapToJson(map[string]string{"teamId": model.NewId(), "email": user.Email}),
+			model.MapToJSON(map[string]string{"teamId": model.NewId(), "email": user.Email}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))
 		defer th.App.DeleteToken(token)
@@ -769,7 +770,7 @@ func TestCreateUserWithToken(t *testing.T) {
 		invitationEmail := model.NewId() + "other-email@test.com"
 		token := model.NewToken(
 			TokenTypeTeamInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id, "email": invitationEmail}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id, "email": invitationEmail}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))
 		newUser, err := th.App.CreateUserWithToken(th.Context, &user, token)
@@ -789,7 +790,7 @@ func TestCreateUserWithToken(t *testing.T) {
 		invitationEmail := model.NewId() + "other-email@test.com"
 		token := model.NewToken(
 			TokenTypeGuestInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id, "email": invitationEmail, "channels": th.BasicChannel.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id, "email": invitationEmail, "channels": th.BasicChannel.Id}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))
 		guest := model.User{Email: strings.ToLower(model.NewId()) + "success+test@example.com", Nickname: "Darth Vader", Username: "vader" + model.NewId(), Password: "passwd1", AuthService: ""}
@@ -819,11 +820,11 @@ func TestCreateUserWithToken(t *testing.T) {
 		grantedInvitationEmail := model.NewId() + "other-email@restricted.com"
 		forbiddenDomainToken := model.NewToken(
 			TokenTypeGuestInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id, "email": forbiddenInvitationEmail, "channels": th.BasicChannel.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id, "email": forbiddenInvitationEmail, "channels": th.BasicChannel.Id}),
 		)
 		grantedDomainToken := model.NewToken(
 			TokenTypeGuestInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id, "email": grantedInvitationEmail, "channels": th.BasicChannel.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id, "email": grantedInvitationEmail, "channels": th.BasicChannel.Id}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(forbiddenDomainToken))
 		require.NoError(t, th.App.Srv().Store.Token().Save(grantedDomainToken))
@@ -866,7 +867,7 @@ func TestCreateUserWithToken(t *testing.T) {
 		invitationEmail := model.NewId() + "other-email@test.com"
 		token := model.NewToken(
 			TokenTypeGuestInvitation,
-			model.MapToJson(map[string]string{"teamId": th.BasicTeam.Id, "email": invitationEmail, "channels": th.BasicChannel.Id}),
+			model.MapToJSON(map[string]string{"teamId": th.BasicTeam.Id, "email": invitationEmail, "channels": th.BasicChannel.Id}),
 		)
 		require.NoError(t, th.App.Srv().Store.Token().Save(token))
 		guest := model.User{
--- a/app/web_conn_test.go
+++ b/app/web_conn_test.go
@@ -254,10 +254,13 @@ func TestWebConnDrainDeadQueue(t *testing.T) {
 			i := seqNum
 			for err == nil {
 				_, buf, err = conn.ReadMessage()
-				ev := model.WebSocketEventFromJson(bytes.NewReader(buf))
-				require.LessOrEqual(t, int(i), limit)
-				assert.Equal(t, i, ev.GetSequence())
-				i++
+				if err != nil && len(buf) > 0 {
+					ev, jsonErr := model.WebSocketEventFromJSON(bytes.NewReader(buf))
+					require.NoError(t, jsonErr)
+					require.LessOrEqual(t, int(i), limit)
+					assert.Equal(t, i, ev.GetSequence())
+					i++
+				}
 			}
 			if _, ok := err.(*websocket.CloseError); !ok {
 				require.NoError(t, err)
--- a/app/web_hub.go
+++ b/app/web_hub.go
@@ -168,10 +168,14 @@ func (s *Server) Publish(message *model.WebSocketEvent) {
 	s.PublishSkipClusterSend(message)

 	if s.Cluster != nil {
+		data, err := message.ToJSON()
+		if err != nil {
+			mlog.Warn("Failed to encode message to JSON", mlog.Err(err))
+		}
 		cm := &model.ClusterMessage{
 			Event:    model.ClusterEventPublish,
 			SendType: model.ClusterSendBestEffort,
-			Data:     message.ToJson(),
+			Data:     data,
 		}

 		if message.EventType() == model.WebsocketEventPosted ||
--- a/app/webhook.go
+++ b/app/webhook.go
@@ -4,7 +4,9 @@
 package app

 import (
+	"bytes"
 	"context"
+	"encoding/json"
 	"errors"
 	"io"
 	"net/http"
@@ -96,7 +98,11 @@ func (a *App) TriggerWebhook(c *request.Context, payload *model.OutgoingWebhookP
 	var body io.Reader
 	var contentType string
 	if hook.ContentType == "application/json" {
-		body = strings.NewReader(payload.ToJSON())
+		js, jsonErr := json.Marshal(payload)
+		if jsonErr != nil {
+			mlog.Warn("Failed to encode to JSON", mlog.Err(jsonErr))
+		}
+		body = bytes.NewReader(js)
 		contentType = "application/json"
 	} else {
 		body = strings.NewReader(payload.ToFormValues())
@@ -164,7 +170,15 @@ func (a *App) doOutgoingWebhookRequest(url string, body io.Reader, contentType s

 	defer resp.Body.Close()

-	return model.OutgoingWebhookResponseFromJson(io.LimitReader(resp.Body, MaxIntegrationResponseSize))
+	var hookResp model.OutgoingWebhookResponse
+	if jsonErr := json.NewDecoder(io.LimitReader(resp.Body, MaxIntegrationResponseSize)).Decode(&hookResp); jsonErr != nil {
+		if jsonErr == io.EOF {
+			return nil, nil
+		}
+		return nil, model.NewAppError("doOutgoingWebhookRequest", "api.unmarshal_error", nil, jsonErr.Error(), http.StatusInternalServerError)
+	}
+
+	return &hookResp, nil
 }

 func SplitWebhookPost(post *model.Post, maxPostSize int) ([]*model.Post, *model.AppError) {
@@ -180,7 +194,7 @@ func SplitWebhookPost(post *model.Post, maxPostSize int) ([]*model.Post, *model.
 		}
 	}

-	if utf8.RuneCountInString(model.StringInterfaceToJson(base.GetProps())) > model.PostPropsMaxUserRunes {
+	if utf8.RuneCountInString(model.StringInterfaceToJSON(base.GetProps())) > model.PostPropsMaxUserRunes {
 		return nil, model.NewAppError("SplitWebhookPost", "web.incoming_webhook.split_props_length.app_error", map[string]interface{}{"Max": model.PostPropsMaxUserRunes}, "", http.StatusBadRequest)
 	}

@@ -213,7 +227,7 @@ func SplitWebhookPost(post *model.Post, maxPostSize int) ([]*model.Post, *model.
 			}
 			origAttachments, _ := newProps["attachments"].([]*model.SlackAttachment)
 			newProps["attachments"] = append(origAttachments, &newAttachment)
-			newPropsString := model.StringInterfaceToJson(newProps)
+			newPropsString := model.StringInterfaceToJSON(newProps)
 			runeCount := utf8.RuneCountInString(newPropsString)

 			if runeCount <= model.PostPropsMaxUserRunes {
--- a/app/webhook_test.go
+++ b/app/webhook_test.go
@@ -673,7 +673,9 @@ func TestTriggerOutGoingWebhookWithUsernameAndIconURL(t *testing.T) {

 			ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 				if testCase.WebhookResponse != nil {
-					w.Write([]byte(testCase.WebhookResponse.ToJson()))
+					js, jsonErr := json.Marshal(testCase.WebhookResponse)
+					require.NoError(t, jsonErr)
+					w.Write(js)
 				} else {
 					w.Write([]byte(`{"text": "sample response text from test server"}`))
 				}
@@ -755,7 +757,7 @@ func TestDoOutgoingWebhookRequest(t *testing.T) {

 		_, err := th.App.doOutgoingWebhookRequest(server.URL, strings.NewReader(""), "application/json")
 		require.Error(t, err)
-		require.IsType(t, &json.SyntaxError{}, err)
+		require.Equal(t, "api.unmarshal_error", err.(*model.AppError).Id)
 	})

 	t.Run("with a large, valid response", func(t *testing.T) {
@@ -766,7 +768,7 @@ func TestDoOutgoingWebhookRequest(t *testing.T) {

 		_, err := th.App.doOutgoingWebhookRequest(server.URL, strings.NewReader(""), "application/json")
 		require.Error(t, err)
-		require.Equal(t, io.ErrUnexpectedEOF, err)
+		require.Equal(t, "api.unmarshal_error", err.(*model.AppError).Id)
 	})

 	t.Run("with a large, invalid response", func(t *testing.T) {
@@ -777,7 +779,7 @@ func TestDoOutgoingWebhookRequest(t *testing.T) {

 		_, err := th.App.doOutgoingWebhookRequest(server.URL, strings.NewReader(""), "application/json")
 		require.Error(t, err)
-		require.IsType(t, &json.SyntaxError{}, err)
+		require.Equal(t, "api.unmarshal_error", err.(*model.AppError).Id)
 	})

 	t.Run("with a slow response", func(t *testing.T) {