fix comment

Author: xiao.dong

src/iceberg/avro/avro_reader.cc

@@ -31,6 +31,7 @@
 #include <avro/Generic.hh>
 #include <avro/GenericDatum.hh>
 
+#include "iceberg/arrow/arrow_error_transform_internal.h"
 #include "iceberg/arrow/arrow_fs_file_io_internal.h"
 #include "iceberg/avro/avro_data_util_internal.h"
 #include "iceberg/avro/avro_schema_util_internal.h"
@@ -51,13 +52,8 @@ Result<std::unique_ptr<AvroInputStream>> CreateInputStream(const ReaderOptions&
   }
 
   auto io = internal::checked_pointer_cast<arrow::ArrowFileSystemFileIO>(options.io);
-  auto result = io->fs()->OpenInputFile(file_info);
-  if (!result.ok()) {
-    return IOError("Failed to open file {} for {}", options.path,
-                   result.status().message());
-  }
-
-  return std::make_unique<AvroInputStream>(result.MoveValueUnsafe(), buffer_size);
+  ICEBERG_ARROW_ASSIGN_OR_RETURN(auto file, io->fs()->OpenInputFile(file_info));
+  return std::make_unique<AvroInputStream>(file, buffer_size);
 }
 
 }  // namespace

src/iceberg/avro/avro_writer.cc

@@ -27,8 +27,8 @@
 #include <arrow/result.h>
 #include <avro/DataFile.hh>
 #include <avro/GenericDatum.hh>
-#include <avro/NodeImpl.hh>
 
+#include "iceberg/arrow/arrow_error_transform_internal.h"
 #include "iceberg/arrow/arrow_fs_file_io_internal.h"
 #include "iceberg/avro/avro_schema_util_internal.h"
 #include "iceberg/avro/avro_stream_internal.h"
@@ -43,12 +43,8 @@ namespace {
 Result<std::unique_ptr<AvroOutputStream>> CreateOutputStream(const WriterOptions& options,
                                                              int64_t buffer_size) {
   auto io = internal::checked_pointer_cast<arrow::ArrowFileSystemFileIO>(options.io);
-  auto result = io->fs()->OpenOutputStream(options.path);
-  if (!result.ok()) {
-    return IOError("Failed to open file {} for {}", options.path,
-                   result.status().message());
-  }
-  return std::make_unique<AvroOutputStream>(result.MoveValueUnsafe(), buffer_size);
+  ICEBERG_ARROW_ASSIGN_OR_RETURN(auto output, io->fs()->OpenOutputStream(options.path));
+  return std::make_unique<AvroOutputStream>(output, buffer_size);
 }
 
 }  // namespace
@@ -120,19 +116,19 @@ Status AvroWriter::Close() {
   return {};
 }
 
-Metrics AvroWriter::metrics() {
+std::optional<Metrics> AvroWriter::metrics() {
   if (impl_->Closed()) {
     // TODO(xiao.dong) implement metrics
     return {};
   }
-  return {};
+  return std::nullopt;
 }
 
-int64_t AvroWriter::length() {
+std::optional<int64_t> AvroWriter::length() {
   if (impl_->Closed()) {
     return impl_->length();
   }
-  return 0;
+  return std::nullopt;
 }
 
 std::vector<int64_t> AvroWriter::split_offsets() { return {}; }

src/iceberg/avro/avro_writer.h

@@ -37,9 +37,9 @@ class ICEBERG_BUNDLE_EXPORT AvroWriter : public Writer {
 
   Status Write(ArrowArray data) final;
 
-  Metrics metrics() final;
+  std::optional<Metrics> metrics() final;
 
-  int64_t length() final;
+  std::optional<int64_t> length() final;
 
   std::vector<int64_t> split_offsets() final;
 

src/iceberg/file_writer.h

@@ -30,7 +30,6 @@
 #include "iceberg/file_format.h"
 #include "iceberg/metrics.h"
 #include "iceberg/result.h"
-#include "iceberg/schema.h"
 #include "iceberg/type_fwd.h"
 
 namespace iceberg {
@@ -70,11 +69,11 @@ class ICEBERG_EXPORT Writer {
 
   /// \brief Get the file statistics.
   /// Only valid after the file is closed.
-  virtual Metrics metrics() = 0;
+  virtual std::optional<Metrics> metrics() = 0;
 
   /// \brief Get the file length.
   /// Only valid after the file is closed.
-  virtual int64_t length() = 0;
+  virtual std::optional<int64_t> length() = 0;
 
   /// \brief Returns a list of recommended split locations, if applicable, empty
   /// otherwise. When available, this information is used for planning scan tasks whose

src/iceberg/metrics.h

@@ -31,7 +31,7 @@ namespace iceberg {
 
 /// \brief Iceberg file format metrics
 struct ICEBERG_EXPORT Metrics {
-  int64_t row_count_ = 0;
+  int64_t row_count = 0;
   std::unordered_map<int64_t, int64_t> column_sizes;
   std::unordered_map<int64_t, int64_t> value_counts;
   std::unordered_map<int64_t, int64_t> null_value_counts;