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ROOT::RNTupleWriter Class Reference

An RNTuple that gets filled with entries (data) and writes them to storage.

An output ntuple can be filled with entries. The caller has to make sure that the data that gets filled into an ntuple is not modified for the time of the Fill() call. The fill call serializes the C++ object into the column format and writes data into the corresponding column page buffers. Writing of the buffers to storage is deferred and can be triggered by FlushCluster() or by destructing the writer. On I/O errors, an exception is thrown.

Definition at line 58 of file RNTupleWriter.hxx.

Public Member Functions

 RNTupleWriter (const RNTupleWriter &)=delete
 
 ~RNTupleWriter ()
 
void CommitCluster (bool commitClusterGroup=false)
 Ensure that the data from the so far seen Fill calls has been written to storage.
 
void CommitDataset ()
 Closes the underlying file (page sink) and expires the model.
 
std::unique_ptr< ROOT::REntryCreateEntry () const
 
std::unique_ptr< ROOT::RNTupleModel::RUpdaterCreateModelUpdater ()
 Get a RNTupleModel::RUpdater that provides limited support for incremental updates to the underlying model, e.g.
 
std::unique_ptr< Experimental::Detail::RRawPtrWriteEntryCreateRawPtrWriteEntry () const
 
void EnableMetrics ()
 
std::size_t Fill ()
 The simplest user interface if the default entry that comes with the ntuple model is used.
 
std::size_t Fill (Experimental::Detail::RRawPtrWriteEntry &entry)
 Fill an RRawPtrWriteEntry into this ntuple.
 
std::size_t Fill (ROOT::REntry &entry)
 Multiple entries can have been instantiated from the ntuple model.
 
void FillNoFlush (Experimental::Detail::RRawPtrWriteEntry &entry, RNTupleFillStatus &status)
 Fill an RRawPtrWriteEntry into this ntuple, but don't commit the cluster.
 
void FillNoFlush (ROOT::REntry &entry, RNTupleFillStatus &status)
 Fill an entry into this ntuple, but don't commit the cluster.
 
void FlushCluster ()
 Flush so far filled entries to storage.
 
void FlushColumns ()
 Flush column data, preparing for CommitCluster or to reduce memory usage.
 
ROOT::NTupleSize_t GetLastCommitted () const
 Return the entry number that was last committed in a cluster.
 
ROOT::NTupleSize_t GetLastCommittedClusterGroup () const
 Return the entry number that was last committed in a cluster group.
 
ROOT::NTupleSize_t GetLastFlushed () const
 Return the entry number that was last flushed in a cluster.
 
const Experimental::Detail::RNTupleMetricsGetMetrics () const
 
const ROOT::RNTupleModelGetModel () const
 
ROOT::NTupleSize_t GetNEntries () const
 Return the number of entries filled so far.
 
RNTupleWriteroperator= (const RNTupleWriter &)=delete
 

Static Public Member Functions

static std::unique_ptr< RNTupleWriterAppend (std::unique_ptr< ROOT::RNTupleModel > model, std::string_view ntupleName, TDirectory &fileOrDirectory, const ROOT::RNTupleWriteOptions &options=ROOT::RNTupleWriteOptions())
 Throws an exception if the model is null.
 
static std::unique_ptr< RNTupleWriterRecreate (std::initializer_list< std::pair< std::string_view, std::string_view > > fields, std::string_view ntupleName, std::string_view storage, const ROOT::RNTupleWriteOptions &options=ROOT::RNTupleWriteOptions())
 
static std::unique_ptr< RNTupleWriterRecreate (std::unique_ptr< ROOT::RNTupleModel > model, std::string_view ntupleName, std::string_view storage, const ROOT::RNTupleWriteOptions &options=ROOT::RNTupleWriteOptions())
 Throws an exception if the model is null.
 

Private Member Functions

 RNTupleWriter (std::unique_ptr< ROOT::RNTupleModel > model, std::unique_ptr< Internal::RPageSink > sink)
 
void CommitClusterGroup ()
 
Internal::RPageSinkGetSink ()
 
ROOT::RNTupleModelGetUpdatableModel ()
 

Static Private Member Functions

static std::unique_ptr< RNTupleWriterCreate (std::unique_ptr< ROOT::RNTupleModel > model, std::unique_ptr< Internal::RPageSink > sink, const ROOT::RNTupleWriteOptions &options)
 Create a writer, potentially wrapping the sink in a RPageSinkBuf.
 

Private Attributes

Experimental::RNTupleFillContext fFillContext
 
ROOT::NTupleSize_t fLastCommittedClusterGroup = 0
 
Experimental::Detail::RNTupleMetrics fMetrics
 
std::unique_ptr< Internal::RPageStorage::RTaskSchedulerfZipTasks
 The page sink's parallel page compression scheduler if IMT is on.
 

Friends

std::unique_ptr< RNTupleWriterInternal::CreateRNTupleWriter (std::unique_ptr< ROOT::RNTupleModel >, std::unique_ptr< Internal::RPageSink >)
 

#include <ROOT/RNTupleWriter.hxx>

Constructor & Destructor Documentation

◆ RNTupleWriter() [1/2]

ROOT::RNTupleWriter::RNTupleWriter ( std::unique_ptr< ROOT::RNTupleModel > model,
std::unique_ptr< Internal::RPageSink > sink )
private

Definition at line 31 of file RNTupleWriter.cxx.

◆ RNTupleWriter() [2/2]

ROOT::RNTupleWriter::RNTupleWriter ( const RNTupleWriter & )
delete

◆ ~RNTupleWriter()

ROOT::RNTupleWriter::~RNTupleWriter ( )

Definition at line 46 of file RNTupleWriter.cxx.

Member Function Documentation

◆ Append()

std::unique_ptr< ROOT::RNTupleWriter > ROOT::RNTupleWriter::Append ( std::unique_ptr< ROOT::RNTupleModel > model,
std::string_view ntupleName,
TDirectory & fileOrDirectory,
const ROOT::RNTupleWriteOptions & options = ROOT::RNTupleWriteOptions() )
static

Throws an exception if the model is null.

Definition at line 98 of file RNTupleWriter.cxx.

◆ CommitCluster()

void ROOT::RNTupleWriter::CommitCluster ( bool commitClusterGroup = false)
inline

Ensure that the data from the so far seen Fill calls has been written to storage.

Definition at line 129 of file RNTupleWriter.hxx.

◆ CommitClusterGroup()

void ROOT::RNTupleWriter::CommitClusterGroup ( )
private

Definition at line 115 of file RNTupleWriter.cxx.

◆ CommitDataset()

void ROOT::RNTupleWriter::CommitDataset ( )

Closes the underlying file (page sink) and expires the model.

Automatically called on destruct. Once the dataset is committed, calls to Fill(), [Commit|Flush]Cluster(), FlushColumns(), CreateEntry(), and model updating fail.

Definition at line 131 of file RNTupleWriter.cxx.

◆ Create()

std::unique_ptr< ROOT::RNTupleWriter > ROOT::RNTupleWriter::Create ( std::unique_ptr< ROOT::RNTupleModel > model,
std::unique_ptr< Internal::RPageSink > sink,
const ROOT::RNTupleWriteOptions & options )
staticprivate

Create a writer, potentially wrapping the sink in a RPageSinkBuf.

Definition at line 55 of file RNTupleWriter.cxx.

◆ CreateEntry()

std::unique_ptr< ROOT::REntry > ROOT::RNTupleWriter::CreateEntry ( ) const
inline

Definition at line 140 of file RNTupleWriter.hxx.

◆ CreateModelUpdater()

std::unique_ptr< ROOT::RNTupleModel::RUpdater > ROOT::RNTupleWriter::CreateModelUpdater ( )
inline

Get a RNTupleModel::RUpdater that provides limited support for incremental updates to the underlying model, e.g.

addition of new fields.

Example: add a new field after the model has been used to construct a RNTupleWriter object

#include <ROOT/RNTuple.hxx>
auto fldFloat = model->MakeField<float>("fldFloat");
auto writer = ROOT::RNTupleWriter::Recreate(std::move(model), "myNTuple", "some/file.root");
auto updater = writer->CreateModelUpdater();
updater->BeginUpdate();
updater->AddField(std::make_unique<RField<float>>("pt"));
updater->CommitUpdate();
// ...
static std::unique_ptr< RNTupleModel > Create()
static std::unique_ptr< RNTupleWriter > Recreate(std::unique_ptr< ROOT::RNTupleModel > model, std::string_view ntupleName, std::string_view storage, const ROOT::RNTupleWriteOptions &options=ROOT::RNTupleWriteOptions())
Throws an exception if the model is null.

Definition at line 177 of file RNTupleWriter.hxx.

◆ CreateRawPtrWriteEntry()

std::unique_ptr< Experimental::Detail::RRawPtrWriteEntry > ROOT::RNTupleWriter::CreateRawPtrWriteEntry ( ) const
inline

Definition at line 141 of file RNTupleWriter.hxx.

◆ EnableMetrics()

void ROOT::RNTupleWriter::EnableMetrics ( )
inline

Definition at line 155 of file RNTupleWriter.hxx.

◆ Fill() [1/3]

std::size_t ROOT::RNTupleWriter::Fill ( )
inline

The simplest user interface if the default entry that comes with the ntuple model is used.

Returns
The number of uncompressed bytes written.

Definition at line 103 of file RNTupleWriter.hxx.

◆ Fill() [2/3]

std::size_t ROOT::RNTupleWriter::Fill ( Experimental::Detail::RRawPtrWriteEntry & entry)
inline

Fill an RRawPtrWriteEntry into this ntuple.

This method will check the entry's model ID to ensure it comes from the writer's own model or throw an exception otherwise.

Returns
The number of uncompressed bytes written.

Definition at line 115 of file RNTupleWriter.hxx.

◆ Fill() [3/3]

std::size_t ROOT::RNTupleWriter::Fill ( ROOT::REntry & entry)
inline

Multiple entries can have been instantiated from the ntuple model.

This method will check the entry's model ID to ensure it comes from the writer's own model or throw an exception otherwise.

Returns
The number of uncompressed bytes written.

Definition at line 107 of file RNTupleWriter.hxx.

◆ FillNoFlush() [1/2]

void ROOT::RNTupleWriter::FillNoFlush ( Experimental::Detail::RRawPtrWriteEntry & entry,
RNTupleFillStatus & status )
inline

Fill an RRawPtrWriteEntry into this ntuple, but don't commit the cluster.

The calling code must pass an RNTupleFillStatus and check RNTupleFillStatus::ShouldFlushCluster.

Definition at line 118 of file RNTupleWriter.hxx.

◆ FillNoFlush() [2/2]

void ROOT::RNTupleWriter::FillNoFlush ( ROOT::REntry & entry,
RNTupleFillStatus & status )
inline

Fill an entry into this ntuple, but don't commit the cluster.

The calling code must pass an RNTupleFillStatus and check RNTupleFillStatus::ShouldFlushCluster.

Definition at line 110 of file RNTupleWriter.hxx.

◆ FlushCluster()

void ROOT::RNTupleWriter::FlushCluster ( )
inline

Flush so far filled entries to storage.

Definition at line 127 of file RNTupleWriter.hxx.

◆ FlushColumns()

void ROOT::RNTupleWriter::FlushColumns ( )
inline

Flush column data, preparing for CommitCluster or to reduce memory usage.

This will trigger compression of pages, but not actually write to storage (unless buffered writing is turned off).

Definition at line 125 of file RNTupleWriter.hxx.

◆ GetLastCommitted()

ROOT::NTupleSize_t ROOT::RNTupleWriter::GetLastCommitted ( ) const
inline

Return the entry number that was last committed in a cluster.

Definition at line 149 of file RNTupleWriter.hxx.

◆ GetLastCommittedClusterGroup()

ROOT::NTupleSize_t ROOT::RNTupleWriter::GetLastCommittedClusterGroup ( ) const
inline

Return the entry number that was last committed in a cluster group.

Definition at line 151 of file RNTupleWriter.hxx.

◆ GetLastFlushed()

ROOT::NTupleSize_t ROOT::RNTupleWriter::GetLastFlushed ( ) const
inline

Return the entry number that was last flushed in a cluster.

Definition at line 147 of file RNTupleWriter.hxx.

◆ GetMetrics()

const Experimental::Detail::RNTupleMetrics & ROOT::RNTupleWriter::GetMetrics ( ) const
inline

Definition at line 156 of file RNTupleWriter.hxx.

◆ GetModel()

const ROOT::RNTupleModel & ROOT::RNTupleWriter::GetModel ( ) const
inline

Definition at line 158 of file RNTupleWriter.hxx.

◆ GetNEntries()

ROOT::NTupleSize_t ROOT::RNTupleWriter::GetNEntries ( ) const
inline

Return the number of entries filled so far.

Definition at line 153 of file RNTupleWriter.hxx.

◆ GetSink()

Internal::RPageSink & ROOT::RNTupleWriter::GetSink ( )
inlineprivate

Definition at line 75 of file RNTupleWriter.hxx.

◆ GetUpdatableModel()

ROOT::RNTupleModel & ROOT::RNTupleWriter::GetUpdatableModel ( )
private

Definition at line 123 of file RNTupleWriter.cxx.

◆ operator=()

RNTupleWriter & ROOT::RNTupleWriter::operator= ( const RNTupleWriter & )
delete

◆ Recreate() [1/2]

std::unique_ptr< ROOT::RNTupleWriter > ROOT::RNTupleWriter::Recreate ( std::initializer_list< std::pair< std::string_view, std::string_view > > fields,
std::string_view ntupleName,
std::string_view storage,
const ROOT::RNTupleWriteOptions & options = ROOT::RNTupleWriteOptions() )
static

Definition at line 82 of file RNTupleWriter.cxx.

◆ Recreate() [2/2]

std::unique_ptr< ROOT::RNTupleWriter > ROOT::RNTupleWriter::Recreate ( std::unique_ptr< ROOT::RNTupleModel > model,
std::string_view ntupleName,
std::string_view storage,
const ROOT::RNTupleWriteOptions & options = ROOT::RNTupleWriteOptions() )
static

Throws an exception if the model is null.

Definition at line 74 of file RNTupleWriter.cxx.

Friends And Related Symbol Documentation

◆ Internal::CreateRNTupleWriter

std::unique_ptr< RNTupleWriter > Internal::CreateRNTupleWriter ( std::unique_ptr< ROOT::RNTupleModel > ,
std::unique_ptr< Internal::RPageSink >  )
friend

Member Data Documentation

◆ fFillContext

Experimental::RNTupleFillContext ROOT::RNTupleWriter::fFillContext
private

Definition at line 67 of file RNTupleWriter.hxx.

◆ fLastCommittedClusterGroup

ROOT::NTupleSize_t ROOT::RNTupleWriter::fLastCommittedClusterGroup = 0
private

Definition at line 70 of file RNTupleWriter.hxx.

◆ fMetrics

Experimental::Detail::RNTupleMetrics ROOT::RNTupleWriter::fMetrics
private

Definition at line 68 of file RNTupleWriter.hxx.

◆ fZipTasks

std::unique_ptr<Internal::RPageStorage::RTaskScheduler> ROOT::RNTupleWriter::fZipTasks
private

The page sink's parallel page compression scheduler if IMT is on.

Needs to be destructed after the page sink (in the fill context) is destructed and so declared before.

Definition at line 66 of file RNTupleWriter.hxx.

Libraries for ROOT::RNTupleWriter:

The documentation for this class was generated from the following files: