Schema migrations for LevelDB (#728)

* Implement schema versions

* Style fixes

* newlines, copyrights, assumptions

* Fix nullability

* Raw ptr -> shared_ptr

* kVersionTableGlobal -> kVersionGlobalTable

* Drop utils, move into static methods

* Drop extra include

* Add a few more comments

* Move version constant into migrations file

* formatting?

* Fix comment

1 files changed, 12 insertions, 1 deletions

diff --git a/Firestore/Source/Local/FSTLevelDB.mm b/Firestore/Source/Local/FSTLevelDB.mm
index 83b932c..d163ed5 100644
--- a/Firestore/Source/Local/FSTLevelDB.mm
+++ b/Firestore/Source/Local/FSTLevelDB.mm
@@ -20,6 +20,7 @@
 
 #import "FIRFirestoreErrors.h"
 #import "Firestore/Source/Core/FSTDatabaseInfo.h"
+#import "Firestore/Source/Local/FSTLevelDBMigrations.h"
 #import "Firestore/Source/Local/FSTLevelDBMutationQueue.h"
 #import "Firestore/Source/Local/FSTLevelDBQueryCache.h"
 #import "Firestore/Source/Local/FSTLevelDBRemoteDocumentCache.h"
@@ -36,6 +37,7 @@ static NSString *const kReservedPathComponent = @"firestore";
 
 using leveldb::DB;
 using leveldb::Options;
+using leveldb::ReadOptions;
 using leveldb::Status;
 using leveldb::WriteOptions;
 
@@ -50,6 +52,15 @@ using leveldb::WriteOptions;
 
 @implementation FSTLevelDB
 
+/**
+ * For now this is paranoid, but perhaps disable that in production builds.
+ */
++ (const ReadOptions)standardReadOptions {
+  ReadOptions options;
+  options.verify_checksums = true;
+  return options;
+}
+
 - (instancetype)initWithDirectory:(NSString *)directory
                        serializer:(FSTLocalSerializer *)serializer {
   if (self = [super init]) {
@@ -115,8 +126,8 @@ using leveldb::WriteOptions;
   if (!database) {
     return NO;
   }
-
   _ptr.reset(database);
+  [FSTLevelDBMigrations runMigrationsOnDB:_ptr];
   return YES;
 }