fix: reduce persistence lag and retry audit deadlocks

server/store/message_batch_test.go

@@ -0,0 +1,42 @@
+package store
+
+import (
+	"testing"
+
+	"github.com/tinode/chat/server/store/types"
+)
+
+func TestAggregatePreparedMessageBatchUpdatesKeepsLatestSeq(t *testing.T) {
+	user1 := types.Uid(1)
+	user2 := types.Uid(2)
+	items := []PreparedMessageBatchItem{
+		{Message: &types.Message{Topic: "p2p-b", From: user1.String(), SeqId: 3}, ReadBySender: true},
+		{Message: &types.Message{Topic: "p2p-a", From: user1.String(), SeqId: 2}, ReadBySender: true},
+		{Message: &types.Message{Topic: "p2p-a", From: user2.String(), SeqId: 5}, ReadBySender: true},
+		{Message: &types.Message{Topic: "p2p-a", From: user1.String(), SeqId: 6}, ReadBySender: true},
+		{Message: &types.Message{Topic: "p2p-b", From: user1.String(), SeqId: 7}, ReadBySender: false},
+		{},
+	}
+
+	topics, reads := aggregatePreparedMessageBatchUpdates(items)
+	if len(topics) != 2 || topics[0].topic != "p2p-a" || topics[0].message.SeqId != 6 ||
+		topics[1].topic != "p2p-b" || topics[1].message.SeqId != 7 {
+		t.Fatalf("unexpected topic updates: %+v", topics)
+	}
+	if len(reads) != 3 {
+		t.Fatalf("read updates=%d want=3: %+v", len(reads), reads)
+	}
+	got := make(map[string]int64, len(reads))
+	for _, update := range reads {
+		got[update.topic+":"+update.from.String()] = update.message.SeqId
+	}
+	for key, want := range map[string]int64{
+		"p2p-a:" + user1.String(): 6,
+		"p2p-a:" + user2.String(): 5,
+		"p2p-b:" + user1.String(): 3,
+	} {
+		if got[key] != want {
+			t.Fatalf("read update %s=%d want=%d; all=%v", key, got[key], want, got)
+		}
+	}
+}