fix: reject unrouted messages without seq

server/db/mysql/group_message_shards.go

@@ -138,6 +138,17 @@ func groupMessageTablesForSeq(q sqlx.QueryerContext, ctx context.Context, tenant
 			return nil, err
 		}
 	}
+	tables := groupMessageShardTablesForSeq(tenantID, routes, seq)
+	if len(tables) == 0 && cached {
+		if routes, err = groupMessageAllShardRoutes(q, ctx, tenantID); err != nil {
+			return nil, err
+		}
+		tables = groupMessageShardTablesForSeq(tenantID, routes, seq)
+	}
+	return tables, nil
+}
+
+func groupMessageShardTablesForSeq(tenantID t.TenantID, routes []store.GroupMessageShardRoute, seq int64) []string {
 	tables := make([]string, 0, 2)
 	for _, route := range routes {
 		if route.MinSeq <= seq && route.MaxSeq >= seq {
@@ -146,7 +157,7 @@ func groupMessageTablesForSeq(q sqlx.QueryerContext, ctx context.Context, tenant
 			}
 		}
 	}
-	return tables, nil
+	return tables
 }
 
 func groupMessageAllShardRoutes(q sqlx.QueryerContext, ctx context.Context, tenantID t.TenantID) ([]store.GroupMessageShardRoute, error) {

server/db/mysql/group_schema_test.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/tinode/chat/server/store"
 	types "github.com/tinode/chat/server/store/types"
 )
 
@@ -75,6 +76,21 @@ func TestGroupMessageShardTableRejectsUnsafeMonth(t *testing.T) {
 	}
 }
 
+func TestGroupMessageShardTablesForSeqFiltersRoutes(t *testing.T) {
+	routes := []store.GroupMessageShardRoute{
+		{Month: "202608", MinSeq: 1, MaxSeq: 20},
+		{Month: "202609", MinSeq: 21, MaxSeq: 100},
+		{Month: "202613", MinSeq: 1, MaxSeq: 1000},
+	}
+	tables := groupMessageShardTablesForSeq(7, routes, 23)
+	if len(tables) != 1 || tables[0] != "im_007_group_messages_202609" {
+		t.Fatalf("unexpected shard tables for seq: %#v", tables)
+	}
+	if tables = groupMessageShardTablesForSeq(7, routes, 101); len(tables) != 0 {
+		t.Fatalf("unexpected shard tables for uncovered seq: %#v", tables)
+	}
+}
+
 func TestTenantPartitionTableNames(t *testing.T) {
 	tests := []struct {
 		tenantID types.TenantID