fix cluster_sync test

arangod/RocksDBEngine/RocksDBTransactionCollection.cpp

@@ -45,7 +45,8 @@ RocksDBTransactionCollection::RocksDBTransactionCollection(
       _operationSize(0),
       _numInserts(0),
       _numUpdates(0),
-      _numRemoves(0) {}
+      _numRemoves(0),
+      _usageLocked(false) {}
 
 RocksDBTransactionCollection::~RocksDBTransactionCollection() {}
 
@@ -153,9 +154,24 @@ int RocksDBTransactionCollection::use(int nestingLevel) {
   }
 
   if (_collection == nullptr) {
-    TRI_vocbase_col_status_e status;
-    LOG_TRX(_transaction, nestingLevel) << "using collection " << _cid;
-    _collection = _transaction->vocbase()->useCollection(_cid, status);
+    // open the collection
+    if (!_transaction->hasHint(transaction::Hints::Hint::LOCK_NEVER) &&
+        !_transaction->hasHint(transaction::Hints::Hint::NO_USAGE_LOCK)) {
+      // use and usage-lock
+      TRI_vocbase_col_status_e status;
+      LOG_TRX(_transaction, nestingLevel) << "using collection " << _cid;
+      _collection = _transaction->vocbase()->useCollection(_cid, status);
+      if (_collection != nullptr) {
+        _usageLocked = true;
+      }
+    } else {
+      // use without usage-lock (lock already set externally)
+      _collection = _transaction->vocbase()->lookupCollection(_cid);
+
+      if (_collection == nullptr) {
+        return TRI_ERROR_ARANGO_COLLECTION_NOT_FOUND;
+      }
+    }
 
     if (_collection == nullptr) {
       int res = TRI_errno();
@@ -206,7 +222,10 @@ void RocksDBTransactionCollection::release() {
     // unuse collection, remove usage-lock
     LOG_TRX(_transaction, 0) << "unusing collection " << _cid;
 
-    _transaction->vocbase()->releaseCollection(_collection);
+    if (_usageLocked) {
+      _transaction->vocbase()->releaseCollection(_collection);
+      _usageLocked = false;
+    }
     _collection = nullptr;
   }
 }

arangod/RocksDBEngine/RocksDBTransactionCollection.h

@@ -96,6 +96,7 @@ class RocksDBTransactionCollection final : public TransactionCollection {
   uint64_t _numInserts;
   uint64_t _numUpdates;
   uint64_t _numRemoves;
+  bool _usageLocked;
 };
 
 }

arangod/RocksDBEngine/RocksDBTransactionState.cpp

@@ -115,6 +115,11 @@ Result RocksDBTransactionState::beginTransaction(transaction::Hints hints) {
   LOG_TRX(this, _nestingLevel) << "beginning " << AccessMode::typeString(_type)
                                << " transaction";
    
+  if (_nestingLevel == 0) { 
+    // set hints
+    _hints = hints;
+  }
+
   Result result = useCollections(_nestingLevel);
 
   if (result.ok()) {

arangod/Transaction/Hints.h

@@ -77,6 +77,10 @@ class Hints {
     unset(static_cast<ValueType>(value));
   }
   
+  inline ValueType toInt() const {
+    return static_cast<ValueType>(_value);
+  }
+
  private:
   ValueType _value;
 };

arangod/V8Server/v8-collection.cpp

@@ -1387,7 +1387,7 @@ static void JS_PropertiesVocbaseCol(
   SingleCollectionTransaction trx(
       transaction::V8Context::Create(collection->vocbase(), true),
       collection->cid(),
-      isModification ? AccessMode::Type::WRITE : AccessMode::Type::READ);
+      isModification ? AccessMode::Type::EXCLUSIVE : AccessMode::Type::READ);
 
   if (!isModification) {
     trx.addHint(transaction::Hints::Hint::NO_USAGE_LOCK);