[Sync] Add transaction_version to sync DB schema and PersistedKernelInfo. Read/save transactions_version when loading/saving kernel info.

BUG=154858

Review URL: https://chromiumcodereview.appspot.com/11088015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@161229 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 74 insertions, 9 deletions

diff --git a/sync/syncable/directory.cc b/sync/syncable/directory.cc
index 4ac17a5..a0a4e24 100644
--- a/sync/syncable/directory.cc
+++ b/sync/syncable/directory.cc
@@ -83,6 +83,7 @@ Directory::PersistedKernelInfo::PersistedKernelInfo()
     : next_id(0) {
   for (int i = FIRST_REAL_MODEL_TYPE; i < MODEL_TYPE_COUNT; ++i) {
     reset_download_progress(ModelTypeFromInt(i));
+    transaction_version[i] = 0;
   }
 }
 
@@ -597,6 +598,7 @@ bool Directory::PurgeEntriesWithTypeIn(ModelTypeSet types) {
            it.Good(); it.Inc()) {
         set_initial_sync_ended_for_type_unsafe(it.Get(), false);
         kernel_->persisted_info.reset_download_progress(it.Get());
+        kernel_->persisted_info.transaction_version[it.Get()] = 0;
       }
     }
   }
diff --git a/sync/syncable/directory.h b/sync/syncable/directory.h
index 49d598c..c123e36 100644
--- a/sync/syncable/directory.h
+++ b/sync/syncable/directory.h
@@ -161,6 +161,13 @@ class Directory {
 
     // Last sync timestamp fetched from the server.
     sync_pb::DataTypeProgressMarker download_progress[MODEL_TYPE_COUNT];
+    // Sync-side transaction version per data type. Monotonically incremented
+    // when updating native model. A copy is also saved in native model.
+    // Later out-of-sync models can be detected and fixed by comparing
+    // transaction versions of sync model and native model.
+    // TODO(hatiaol): implement detection and fixing of out-of-sync models.
+    //                Bug 154858.
+    int64 transaction_version[MODEL_TYPE_COUNT];
     // true iff we ever reached the end of the changelog.
     ModelTypeSet initial_sync_ended;
     // The store birthday we were given by the server. Contents are opaque to
diff --git a/sync/syncable/directory_backing_store.cc b/sync/syncable/directory_backing_store.cc
index fde0279..4f9febf 100644
--- a/sync/syncable/directory_backing_store.cc
+++ b/sync/syncable/directory_backing_store.cc
@@ -40,7 +40,7 @@ static const string::size_type kUpdateStatementBufferSize = 2048;
 
 // Increment this version whenever updating DB tables.
 extern const int32 kCurrentDBVersion;  // Global visibility for our unittest.
-const int32 kCurrentDBVersion = 81;
+const int32 kCurrentDBVersion = 82;
 
 // Iterate over the fields of |entry| and bind each to |statement| for
 // updating.  Returns the number of args bound.
@@ -236,8 +236,9 @@ bool DirectoryBackingStore::SaveChanges(
     sql::Statement s2(db_->GetCachedStatement(
             SQL_FROM_HERE,
             "INSERT OR REPLACE "
-            "INTO models (model_id, progress_marker, initial_sync_ended) "
-            "VALUES (?, ?, ?)"));
+            "INTO models (model_id, progress_marker, initial_sync_ended, "
+            "             transaction_version) "
+            "VALUES (?, ?, ?, ?)"));
 
     for (int i = FIRST_REAL_MODEL_TYPE; i < MODEL_TYPE_COUNT; ++i) {
       // We persist not ModelType but rather a protobuf-derived ID.
@@ -247,6 +248,7 @@ bool DirectoryBackingStore::SaveChanges(
       s2.BindBlob(0, model_id.data(), model_id.length());
       s2.BindBlob(1, progress_marker.data(), progress_marker.length());
       s2.BindBool(2, info.initial_sync_ended.Has(ModelTypeFromInt(i)));
+      s2.BindInt64(3, info.transaction_version[i]);
       if (!s2.Run())
         return false;
       DCHECK_EQ(db_->GetLastChangeCount(), 1);
@@ -350,6 +352,12 @@ bool DirectoryBackingStore::InitializeTables() {
       version_on_disk = 81;
   }
 
+  // Version 82 migration added transaction_version column per data type.
+  if (version_on_disk == 81) {
+    if (MigrateVersion81To82())
+      version_on_disk = 82;
+  }
+
   // If one of the migrations requested it, drop columns that aren't current.
   // It's only safe to do this after migrating all the way to the current
   // version.
@@ -488,8 +496,8 @@ bool DirectoryBackingStore::LoadInfo(Directory::KernelLoadInfo* info) {
   {
     sql::Statement s(
         db_->GetUniqueStatement(
-            "SELECT model_id, progress_marker, initial_sync_ended "
-            "FROM models"));
+            "SELECT model_id, progress_marker, initial_sync_ended, "
+            "transaction_version FROM models"));
 
     while (s.Step()) {
       ModelType type = ModelIdToModelTypeEnum(s.ColumnBlob(0),
@@ -499,6 +507,7 @@ bool DirectoryBackingStore::LoadInfo(Directory::KernelLoadInfo* info) {
             s.ColumnBlob(1), s.ColumnByteLength(1));
         if (s.ColumnBool(2))
           info->kernel_info.initial_sync_ended.Put(type);
+        info->kernel_info.transaction_version[type] = s.ColumnInt64(3);
       }
     }
     if (!s.Succeeded())
@@ -1043,6 +1052,26 @@ bool DirectoryBackingStore::MigrateVersion80To81() {
   return true;
 }
 
+bool DirectoryBackingStore::MigrateVersion81To82() {
+  // Version 82 added transaction_version to kernel info. But if user is
+  // migrating from 74 or before, 74->75 migration would recreate models table
+  // that already has transaction_version column.
+  if (db_->DoesColumnExist("models", "transaction_version")) {
+    SetVersion(82);
+    return true;
+  }
+
+  if (!db_->Execute(
+      "ALTER TABLE models ADD COLUMN transaction_version BIGINT default 0"))
+    return false;
+  sql::Statement update(db_->GetUniqueStatement(
+      "UPDATE models SET transaction_version = 0"));
+  if (!update.Run())
+    return false;
+  SetVersion(82);
+  return true;
+}
+
 bool DirectoryBackingStore::CreateTables() {
   DVLOG(1) << "First run, creating tables";
   // Create two little tables share_version and share_info
@@ -1141,7 +1170,7 @@ bool DirectoryBackingStore::CreateV71ModelsTable() {
 }
 
 bool DirectoryBackingStore::CreateModelsTable() {
-  // This is the current schema for the Models table, from version 75
+  // This is the current schema for the Models table, from version 81
   // onward.  If you change the schema, you'll probably want to double-check
   // the use of this function in the v74-v75 migration.
   return db_->Execute(
@@ -1151,7 +1180,8 @@ bool DirectoryBackingStore::CreateModelsTable() {
       // Gets set if the syncer ever gets updates from the
       // server and the server returns 0.  Lets us detect the
       // end of the initial sync.
-      "initial_sync_ended BOOLEAN default 0)");
+      "initial_sync_ended BOOLEAN default 0, "
+      "transaction_version BIGINT default 0)");
 }
 
 bool DirectoryBackingStore::CreateShareInfoTable(bool is_temporary) {
diff --git a/sync/syncable/directory_backing_store.h b/sync/syncable/directory_backing_store.h
index 21bc8c2..ae2b189 100644
--- a/sync/syncable/directory_backing_store.h
+++ b/sync/syncable/directory_backing_store.h
@@ -156,6 +156,7 @@ class DirectoryBackingStore : public base::NonThreadSafe {
   bool MigrateVersion78To79();
   bool MigrateVersion79To80();
   bool MigrateVersion80To81();
+  bool MigrateVersion81To82();
 
   scoped_ptr<sql::Connection> db_;
   sql::Statement save_entry_statement_;
diff --git a/sync/syncable/directory_backing_store_unittest.cc b/sync/syncable/directory_backing_store_unittest.cc
index 457a702..3cd53c1 100644
--- a/sync/syncable/directory_backing_store_unittest.cc
+++ b/sync/syncable/directory_backing_store_unittest.cc
@@ -116,10 +116,12 @@ class DirectoryBackingStoreTest : public MigrationTest {};
 
 // Generated via:
 //
-// ruby -ane '$F[1].sub!("LEGACY_", ""); $F[2] = Integer($F[2].sub!("LL", "")) / 10000 - 11644473600000; print "#{$F[0]} #{$F[1]} #{$F[2]}LL\n"'
+// ruby -ane '$F[1].sub!("LEGACY_", ""); $F[2] = Integer($F[2].sub!("LL", "")) /
+//    10000 - 11644473600000; print "#{$F[0]} #{$F[1]} #{$F[2]}LL"'
 //
 // Magic numbers taken from
-// http://stackoverflow.com/questions/5398557/java-library-for-dealing-with-win32-filetime .
+// http://stackoverflow.com/questions/5398557/
+//    java-library-for-dealing-with-win32-filetime .
 
 // Now we store them in Java format (ms since the Unix epoch).
 #define META_PROTO_TIMES_1 1263522064032LL
@@ -2370,6 +2372,22 @@ TEST_F(DirectoryBackingStoreTest, DetectInvalidOrdinal) {
             dbs->Load(&entry_bucket, &kernel_load_info));
 }
 
+TEST_F(DirectoryBackingStoreTest, MigrateVersion81To82) {
+  sql::Connection connection;
+  ASSERT_TRUE(connection.OpenInMemory());
+  SetUpVersion81Database(&connection);
+  ASSERT_FALSE(connection.DoesColumnExist("models", "transaction_version"));
+
+  scoped_ptr<TestDirectoryBackingStore> dbs(
+      new TestDirectoryBackingStore(GetUsername(), &connection));
+  ASSERT_FALSE(dbs->needs_column_refresh_);
+  ASSERT_TRUE(dbs->MigrateVersion81To82());
+  ASSERT_EQ(82, dbs->GetVersion());
+  ASSERT_FALSE(dbs->needs_column_refresh_);
+
+  ASSERT_TRUE(connection.DoesColumnExist("models", "transaction_version"));
+}
+
 TEST_P(MigrationTest, ToCurrentVersion) {
   sql::Connection connection;
   ASSERT_TRUE(connection.OpenInMemory());
@@ -2416,6 +2434,9 @@ TEST_P(MigrationTest, ToCurrentVersion) {
     case 80:
       SetUpVersion80Database(&connection);
       break;
+    case 81:
+      SetUpVersion81Database(&connection);
+      break;
     default:
       // If you see this error, it may mean that you've increased the
       // database version number but you haven't finished adding unit tests
@@ -2495,6 +2516,9 @@ TEST_P(MigrationTest, ToCurrentVersion) {
   // Column added in version 78.
   ASSERT_TRUE(connection.DoesColumnExist("metas", "base_server_specifics"));
 
+  // Column added in version 82.
+  ASSERT_TRUE(connection.DoesColumnExist("models", "transaction_version"));
+
   // Check download_progress state (v75 migration)
   ASSERT_EQ(694,
       dir_info.kernel_info.download_progress[BOOKMARKS]
diff --git a/sync/test/test_directory_backing_store.h b/sync/test/test_directory_backing_store.h
index b0e230a..bb90c65 100644
--- a/sync/test/test_directory_backing_store.h
+++ b/sync/test/test_directory_backing_store.h
@@ -43,6 +43,7 @@ class TestDirectoryBackingStore : public DirectoryBackingStore {
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion78To79);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion79To80);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion80To81);
+  FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, MigrateVersion81To82);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, DetectInvalidOrdinal);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, ModelTypeIds);
   FRIEND_TEST_ALL_PREFIXES(DirectoryBackingStoreTest, Corruption);