From: delthas <delthas@dille.cc>
To: ~emersion/soju-dev@lists.sr.ht
Cc: delthas <delthas@dille.cc>
Subject: [PATCH] Truncate message times to the second when using the FS message store
Date: Tue, 18 Oct 2022 14:57:33 +0200
Message-Id: <20221018125733.28721-1-delthas@dille.cc>

The FS message store truncates message times to the second.

This means that a message sent out as 2020-01-01T00:00:00.123Z could be
sent later as part of a CHATHISTORY batch as 2020-01-01T00:00:00.000Z,
which could cause issues in clients.

One such issue is a client sending a MARKREAD for
2020-01-01T00:00:00.000Z, with another client considering the
2020-01-01T00:00:00.123Z message it has as unread.

This fixes the issue by truncating all message times to the second when
using the FS message store.
---
 downstream.go  |  6 +++---
 msgstore/fs.go |  5 +++++
 upstream.go    |  8 ++++++--
 user.go        | 11 +++++++++++
 4 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/downstream.go b/downstream.go
index 6302a5c..45c8576 100644
--- a/downstream.go
+++ b/downstream.go
@@ -2280,7 +2280,7 @@ func (dc *downstreamConn) handleMessageRegistered(ctx context.Context, msg *irc.
 				dc.logger.Printf("broadcasting bouncer-wide %v: %v", msg.Command, text)
 
 				broadcastTags := tags.Copy()
-				broadcastTags["time"] = irc.TagValue(xirc.FormatServerTime(time.Now()))
+				broadcastTags["time"] = irc.TagValue(dc.user.FormatServerTime(time.Now()))
 				broadcastMsg := &irc.Message{
 					Tags:    broadcastTags,
 					Prefix:  servicePrefix,
@@ -2306,7 +2306,7 @@ func (dc *downstreamConn) handleMessageRegistered(ctx context.Context, msg *irc.
 			if casemapASCII(name) == serviceNickCM {
 				if dc.caps.IsEnabled("echo-message") {
 					echoTags := tags.Copy()
-					echoTags["time"] = irc.TagValue(xirc.FormatServerTime(time.Now()))
+					echoTags["time"] = irc.TagValue(dc.user.FormatServerTime(time.Now()))
 					dc.SendMessage(&irc.Message{
 						Tags:    echoTags,
 						Prefix:  dc.prefix(),
@@ -2350,7 +2350,7 @@ func (dc *downstreamConn) handleMessageRegistered(ctx context.Context, msg *irc.
 				}
 
 				echoTags := tags.Copy()
-				echoTags["time"] = irc.TagValue(xirc.FormatServerTime(time.Now()))
+				echoTags["time"] = irc.TagValue(dc.user.FormatServerTime(time.Now()))
 				if uc.account != "" {
 					echoTags["account"] = irc.TagValue(uc.account)
 				}
diff --git a/msgstore/fs.go b/msgstore/fs.go
index 53f9977..65db04e 100644
--- a/msgstore/fs.go
+++ b/msgstore/fs.go
@@ -96,6 +96,11 @@ var (
 	_ RenameNetworkStore = (*fsMessageStore)(nil)
 )
 
+func IsFSStore(store Store) bool {
+	_, ok := store.(*fsMessageStore)
+	return ok
+}
+
 func NewFSStore(root string, user *database.User) *fsMessageStore {
 	return &fsMessageStore{
 		root:  filepath.Join(root, escapeFilename(user.Username)),
diff --git a/upstream.go b/upstream.go
index e1030a2..4aa3ff9 100644
--- a/upstream.go
+++ b/upstream.go
@@ -485,8 +485,12 @@ func (uc *upstreamConn) handleMessage(ctx context.Context, msg *irc.Message) err
 		msg.Prefix = uc.serverPrefix
 	}
 
-	if _, ok := msg.Tags["time"]; !ok && !isNumeric(msg.Command) {
-		msg.Tags["time"] = irc.TagValue(xirc.FormatServerTime(time.Now()))
+	if !isNumeric(msg.Command) {
+		t, err := time.Parse(xirc.ServerTimeLayout, string(msg.Tags["time"]))
+		if err != nil {
+			t = time.Now()
+		}
+		msg.Tags["time"] = irc.TagValue(uc.user.FormatServerTime(t))
 	}
 
 	switch msg.Command {
diff --git a/user.go b/user.go
index 7468483..43ea79a 100644
--- a/user.go
+++ b/user.go
@@ -13,6 +13,8 @@ import (
 	"strings"
 	"time"
 
+	"git.sr.ht/~emersion/soju/xirc"
+
 	"github.com/SherClockHolmes/webpush-go"
 	"gopkg.in/irc.v3"
 
@@ -1114,6 +1116,15 @@ func (u *user) hasPersistentMsgStore() bool {
 	return !msgstore.IsMemoryStore(u.msgStore)
 }
 
+func (u *user) FormatServerTime(t time.Time) string {
+	if u.msgStore != nil && msgstore.IsFSStore(u.msgStore) {
+		// The FS message store truncates message timestamps to the second,
+		// so truncate them here to get consistent timestamps.
+		t = t.Truncate(time.Second)
+	}
+	return xirc.FormatServerTime(t)
+}
+
 // localAddrForHost returns the local address to use when connecting to host.
 // A nil address is returned when the OS should automatically pick one.
 func (u *user) localTCPAddrForHost(ctx context.Context, host string) (*net.TCPAddr, error) {

base-commit: 90be9a8ab95a06d7e622852bf312116c7e199d48
-- 
2.17.1