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alesapin 2022-06-30 14:27:47 +02:00
parent 1ff4222661
commit c5943d0384
1 changed files with 10 additions and 0 deletions
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10
src/Disks/ObjectStorages/DiskObjectStorageTransaction.cpp
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@ -527,6 +527,16 @@ std::unique_ptr<WriteBufferFromFileBase> DiskObjectStorageTransaction::writeFile
{
create_metadata_callback = [write_op = write_operation.get(), mode, path, blob_name] (size_t count)
{
/// This callback called in WriteBuffer finalize method -- only there we actually know
/// how many bytes were written. We don't control when this finalize method will be called
/// so here we just modify operation itself, but don't execute anything (and don't modify metadata transaction).
/// Otherwise it's possible to get reorder of operations, like:
/// tx->createDirectory(xxx) -- will add metadata operation in execute
/// buf1 = tx->writeFile(xxx/yyy.bin)
/// buf2 = tx->writeFile(xxx/zzz.bin)
/// ...
/// buf1->finalize() // shouldn't do anything with metadata operations, just memoize what to do
/// tx->commit()
write_op->setOnExecute([mode, path, blob_name, count](MetadataTransactionPtr tx)
{
if (mode == WriteMode::Rewrite)