Files
mostlymatter/services/sharedchannel/sync_send.go
2021-05-11 22:29:30 +03:00

515 строки
15 KiB
Go

// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
// See LICENSE.txt for license information.
package sharedchannel
import (
"context"
"encoding/json"
"fmt"
"sync"
"time"
"github.com/mattermost/mattermost-server/v5/model"
"github.com/mattermost/mattermost-server/v5/services/remotecluster"
"github.com/mattermost/mattermost-server/v5/shared/i18n"
"github.com/mattermost/mattermost-server/v5/shared/mlog"
)
type syncTask struct {
id string
channelId string
remoteId string
AddedAt time.Time
retryCount int
retryPost *model.Post
schedule time.Time
}
func newSyncTask(channelId string, remoteId string, retryPost *model.Post) syncTask {
var postId string
if retryPost != nil {
postId = retryPost.Id
}
return syncTask{
id: channelId + remoteId + postId, // combination of ids to avoid duplicates
channelId: channelId,
remoteId: remoteId, // empty means update all remote clusters
retryPost: retryPost,
schedule: time.Now(),
}
}
// incRetry increments the retry counter and returns true if MaxRetries not exceeded.
func (st *syncTask) incRetry() bool {
st.retryCount++
return st.retryCount <= MaxRetries
}
// NotifyChannelChanged is called to indicate that a shared channel has been modified,
// thus triggering an update to all remote clusters.
func (scs *Service) NotifyChannelChanged(channelId string) {
if rcs := scs.server.GetRemoteClusterService(); rcs == nil {
return
}
task := newSyncTask(channelId, "", nil)
task.schedule = time.Now().Add(NotifyMinimumDelay)
scs.addTask(task)
}
// ForceSyncForRemote causes all channels shared with the remote to be synchronized.
func (scs *Service) ForceSyncForRemote(rc *model.RemoteCluster) {
if rcs := scs.server.GetRemoteClusterService(); rcs == nil {
return
}
// fetch all channels shared with this remote.
opts := model.SharedChannelRemoteFilterOpts{
RemoteId: rc.RemoteId,
}
scrs, err := scs.server.GetStore().SharedChannel().GetRemotes(opts)
if err != nil {
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceError, "Failed to fetch shared channel remotes",
mlog.String("remote", rc.DisplayName),
mlog.String("remoteId", rc.RemoteId),
mlog.Err(err),
)
return
}
for _, scr := range scrs {
task := newSyncTask(scr.ChannelId, rc.RemoteId, nil)
task.schedule = time.Now().Add(NotifyMinimumDelay)
scs.addTask(task)
}
}
// addTask adds or re-adds a task to the queue.
func (scs *Service) addTask(task syncTask) {
task.AddedAt = time.Now()
scs.mux.Lock()
if _, ok := scs.tasks[task.id]; !ok {
scs.tasks[task.id] = task
}
scs.mux.Unlock()
// wake up the sync goroutine
select {
case scs.changeSignal <- struct{}{}:
default:
// that's ok, the sync routine is already busy
}
}
// syncLoop is called via a dedicated goroutine to wait for notifications of channel changes and
// updates each remote based on those changes.
func (scs *Service) syncLoop(done chan struct{}) {
// create a timer to periodically check the task queue, but only if there is
// a delayed task in the queue.
delay := time.NewTimer(NotifyMinimumDelay)
defer stopTimer(delay)
// wait for channel changed signal and update for oldest task.
for {
select {
case <-scs.changeSignal:
if wait := scs.doSync(); wait > 0 {
stopTimer(delay)
delay.Reset(wait)
}
case <-delay.C:
if wait := scs.doSync(); wait > 0 {
delay.Reset(wait)
}
case <-done:
return
}
}
}
func stopTimer(timer *time.Timer) {
timer.Stop()
select {
case <-timer.C:
default:
}
}
// doSync checks the task queue for any tasks to be processed and processes all that are ready.
// If any delayed tasks remain in queue then the duration until the next scheduled task is returned.
func (scs *Service) doSync() time.Duration {
var task syncTask
var ok bool
var shortestWait time.Duration
for {
task, ok, shortestWait = scs.removeOldestTask()
if !ok {
break
}
if err := scs.processTask(task); err != nil {
// put task back into map so it will update again
if task.incRetry() {
scs.addTask(task)
} else {
scs.server.GetLogger().Error("Failed to synchronize shared channel",
mlog.String("channelId", task.channelId),
mlog.String("remoteId", task.remoteId),
mlog.Err(err),
)
}
}
}
return shortestWait
}
// removeOldestTask removes and returns the oldest task in the task map.
// A task coming in via NotifyChannelChanged must stay in queue for at least
// `NotifyMinimumDelay` to ensure we don't go nuts trying to sync during a bulk update.
// If no tasks are available then false is returned.
func (scs *Service) removeOldestTask() (syncTask, bool, time.Duration) {
scs.mux.Lock()
defer scs.mux.Unlock()
var oldestTask syncTask
var oldestKey string
var shortestWait time.Duration
for key, task := range scs.tasks {
// check if task is ready
if wait := time.Until(task.schedule); wait > 0 {
if wait < shortestWait || shortestWait == 0 {
shortestWait = wait
}
continue
}
// task is ready; check if it's the oldest ready task
if task.AddedAt.Before(oldestTask.AddedAt) || oldestTask.AddedAt.IsZero() {
oldestKey = key
oldestTask = task
}
}
if oldestKey != "" {
delete(scs.tasks, oldestKey)
return oldestTask, true, shortestWait
}
return oldestTask, false, shortestWait
}
// processTask updates one or more remote clusters with any new channel content.
func (scs *Service) processTask(task syncTask) error {
var err error
var remotes []*model.RemoteCluster
if task.remoteId == "" {
filter := model.RemoteClusterQueryFilter{
InChannel: task.channelId,
OnlyConfirmed: true,
}
remotes, err = scs.server.GetStore().RemoteCluster().GetAll(filter)
if err != nil {
return err
}
} else {
rc, err := scs.server.GetStore().RemoteCluster().Get(task.remoteId)
if err != nil {
return err
}
if !rc.IsOnline() {
return fmt.Errorf("Failed updating shared channel '%s' for offline remote cluster '%s'", task.channelId, rc.DisplayName)
}
remotes = []*model.RemoteCluster{rc}
}
for _, rc := range remotes {
rtask := task
rtask.remoteId = rc.RemoteId
if err := scs.updateForRemote(rtask, rc); err != nil {
// retry...
if rtask.incRetry() {
scs.addTask(rtask)
} else {
scs.server.GetLogger().Error("Failed to synchronize shared channel for remote cluster",
mlog.String("channelId", rtask.channelId),
mlog.String("remote", rc.DisplayName),
mlog.String("remoteId", rtask.remoteId),
mlog.Err(err),
)
}
}
}
return nil
}
// updateForRemote updates a remote cluster with any new posts/reactions for a specific
// channel. If many changes are found, only the oldest X changes are sent and the channel
// is re-added to the task map. This ensures no channels are starved for updates even if some
// channels are very active.
func (scs *Service) updateForRemote(task syncTask, rc *model.RemoteCluster) error {
rcs := scs.server.GetRemoteClusterService()
if rcs == nil {
return fmt.Errorf("cannot update remote cluster for channel id %s; Remote Cluster Service not enabled", task.channelId)
}
scr, err := scs.server.GetStore().SharedChannel().GetRemoteByIds(task.channelId, rc.RemoteId)
if err != nil {
return err
}
var posts []*model.Post
var repeat bool
nextSince := scr.NextSyncAt
if task.retryPost != nil {
posts = []*model.Post{task.retryPost}
} else {
result, err2 := scs.getPostsSince(task.channelId, rc, scr.NextSyncAt)
if err2 != nil {
return err2
}
posts = result.posts
repeat = result.hasMore
nextSince = result.nextSince
}
if len(posts) == 0 {
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceDebug, "sync task found zero posts; skipping sync",
mlog.String("remote", rc.DisplayName),
mlog.String("channel_id", task.channelId),
mlog.Int64("lastSyncAt", scr.NextSyncAt),
mlog.Int64("nextSince", nextSince),
mlog.Bool("repeat", repeat),
)
return nil
}
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceDebug, "sync task found posts to sync",
mlog.String("remote", rc.DisplayName),
mlog.String("channel_id", task.channelId),
mlog.Int64("lastSyncAt", scr.NextSyncAt),
mlog.Int64("nextSince", nextSince),
mlog.Int("count", len(posts)),
mlog.Bool("repeat", repeat),
)
if !rc.IsOnline() {
scs.notifyRemoteOffline(posts, rc)
return nil
}
syncMessages, err := scs.postsToSyncMessages(posts, task.channelId, rc, scr.NextSyncAt)
if err != nil {
return err
}
if len(syncMessages) == 0 {
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceDebug, "sync task, all messages filtered out; skipping sync",
mlog.String("remote", rc.DisplayName),
mlog.String("channel_id", task.channelId),
mlog.Bool("repeat", repeat),
)
// All posts were filtered out, meaning no need to send them. Fast forward SharedChannelRemote's NextSyncAt.
scs.updateNextSyncForRemote(scr.Id, rc, nextSince)
// if there are more posts eligible to sync then schedule another sync
if repeat {
scs.addTask(newSyncTask(task.channelId, task.remoteId, nil))
}
return nil
}
scs.sendAttachments(syncMessages, rc)
b, err := json.Marshal(syncMessages)
if err != nil {
return err
}
msg := model.NewRemoteClusterMsg(TopicSync, b)
if scs.server.GetLogger().IsLevelEnabled(mlog.LvlSharedChannelServiceMessagesOutbound) {
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceMessagesOutbound, "outbound message",
mlog.String("remote", rc.DisplayName),
mlog.Int64("NextSyncAt", scr.NextSyncAt),
mlog.String("msg", string(b)),
)
}
ctx, cancel := context.WithTimeout(context.Background(), remotecluster.SendTimeout)
defer cancel()
var wg sync.WaitGroup
wg.Add(1)
err = rcs.SendMsg(ctx, msg, rc, func(msg model.RemoteClusterMsg, rc *model.RemoteCluster, resp *remotecluster.Response, err error) {
defer wg.Done()
if err != nil {
return // this means the response could not be parsed; already logged
}
var syncResp SyncResponse
if err2 := json.Unmarshal(resp.Payload, &syncResp); err2 != nil {
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceError, "invalid sync response after update shared channel",
mlog.String("remote", rc.DisplayName),
mlog.Err(err2),
)
}
// Any Post(s) that failed to save on remote side are included in an array of post ids in the Response payload.
// Handle each error by retrying the post a fixed number of times before giving up.
for _, p := range syncResp.PostErrors {
scs.handlePostError(p, task, rc)
}
// update NextSyncAt for all the users that were synchronized
scs.updateSyncUsers(syncResp.UsersSyncd, task.channelId, rc, nextSince)
})
wg.Wait()
if err == nil {
// Optimistically update SharedChannelRemote's NextSyncAt; if any posts failed they will be retried.
scs.updateNextSyncForRemote(scr.Id, rc, nextSince)
}
if repeat {
scs.addTask(newSyncTask(task.channelId, task.remoteId, nil))
}
return err
}
func (scs *Service) sendAttachments(syncMessages []syncMsg, rc *model.RemoteCluster) {
for _, sm := range syncMessages {
for _, fi := range sm.Attachments {
if err := scs.sendAttachmentForRemote(fi, sm.Post, rc); err != nil {
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceError, "error syncing attachment for post",
mlog.String("remote", rc.DisplayName),
mlog.String("post_id", sm.Post.Id),
mlog.String("file_id", fi.Id),
mlog.Err(err),
)
}
}
}
}
func (scs *Service) handlePostError(postId string, task syncTask, rc *model.RemoteCluster) {
if task.retryPost != nil && task.retryPost.Id == postId {
// this was a retry for specific post that failed previously. Try again if within MaxRetries.
if task.incRetry() {
scs.addTask(task)
} else {
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceError, "error syncing post",
mlog.String("remote", rc.DisplayName),
mlog.String("post_id", postId),
)
}
return
}
// this post failed as part of a group of posts. Retry as an individual post.
post, err := scs.server.GetStore().Post().GetSingle(postId, true)
if err != nil {
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceError, "error fetching post for sync retry",
mlog.String("remote", rc.DisplayName),
mlog.String("post_id", postId),
)
return
}
scs.addTask(newSyncTask(task.channelId, task.remoteId, post))
}
// notifyRemoteOffline creates an ephemeral post to the author for any posts created recently to remotes
// that are offline.
func (scs *Service) notifyRemoteOffline(posts []*model.Post, rc *model.RemoteCluster) {
// only send one ephemeral post per author.
notified := make(map[string]bool)
// range the slice in reverse so the newest posts are visited first; this ensures an ephemeral
// get added where it is mostly likely to be seen.
for i := len(posts) - 1; i >= 0; i-- {
post := posts[i]
if didNotify := notified[post.UserId]; didNotify {
continue
}
postCreateAt := model.GetTimeForMillis(post.CreateAt)
if post.DeleteAt == 0 && post.UserId != "" && time.Since(postCreateAt) < NotifyRemoteOfflineThreshold {
T := scs.getUserTranslations(post.UserId)
ephemeral := &model.Post{
ChannelId: post.ChannelId,
Message: T("sharedchannel.cannot_deliver_post", map[string]interface{}{"Remote": rc.DisplayName}),
CreateAt: post.CreateAt + 1,
}
scs.app.SendEphemeralPost(post.UserId, ephemeral)
notified[post.UserId] = true
}
}
}
func (scs *Service) updateNextSyncForRemote(scrId string, rc *model.RemoteCluster, nextSyncAt int64) {
if nextSyncAt == 0 {
return
}
if err := scs.server.GetStore().SharedChannel().UpdateRemoteNextSyncAt(scrId, nextSyncAt); err != nil {
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceError, "error updating NextSyncAt for shared channel remote",
mlog.String("remote", rc.DisplayName),
mlog.Err(err),
)
return
}
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceDebug, "updated NextSyncAt for remote",
mlog.String("remote_id", rc.RemoteId),
mlog.String("remote", rc.DisplayName),
mlog.Int64("next_update_at", nextSyncAt),
)
}
func (scs *Service) updateSyncUsers(userIds []string, channelID string, rc *model.RemoteCluster, lastSyncAt int64) {
for _, uid := range userIds {
scu, err := scs.server.GetStore().SharedChannel().GetUser(uid, channelID, rc.RemoteId)
if err != nil {
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceError, "error getting user for lastSyncAt update",
mlog.String("remote", rc.DisplayName),
mlog.String("user_id", uid),
mlog.Err(err),
)
continue
}
if err := scs.server.GetStore().SharedChannel().UpdateUserLastSyncAt(scu.Id, lastSyncAt); err != nil {
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceError, "error updating lastSyncAt for user",
mlog.String("remote", rc.DisplayName),
mlog.String("user_id", uid),
mlog.String("channel_id", channelID),
mlog.Err(err),
)
} else {
scs.server.GetLogger().Log(mlog.LvlSharedChannelServiceDebug, "updated lastSyncAt for user",
mlog.String("remote", rc.DisplayName),
mlog.String("user_id", scu.UserId),
mlog.String("channel_id", channelID),
mlog.Int64("last_update_at", lastSyncAt),
)
}
}
}
func (scs *Service) getUserTranslations(userId string) i18n.TranslateFunc {
var locale string
user, err := scs.server.GetStore().User().Get(context.Background(), userId)
if err == nil {
locale = user.Locale
}
if locale == "" {
locale = model.DEFAULT_LOCALE
}
return i18n.GetUserTranslations(locale)
}