wgtmac commented on code in PR #143:
URL: https://github.com/apache/iceberg-cpp/pull/143#discussion_r2192006916


##########
src/iceberg/manifest_reader_internal.cc:
##########
@@ -0,0 +1,244 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include "manifest_reader_internal.h"
+
+#include <array>
+
+#include <nanoarrow/nanoarrow.h>
+
+#include "iceberg/arrow_c_data_guard_internal.h"
+#include "iceberg/manifest_entry.h"
+#include "iceberg/manifest_list.h"
+#include "iceberg/schema.h"
+#include "iceberg/schema_internal.h"
+#include "iceberg/type.h"
+
+namespace iceberg {
+
+#define ARROW_RETURN_IF_NOT_OK(status, error)                      \
+  if (status != NANOARROW_OK) {                                    \
+    return InvalidArrowData("NanoArrow error: {}", error.message); \

Review Comment:
   ```suggestion
       return InvalidArrowData("Nanoarrow error: {}", error.message); \
   ```



##########
src/iceberg/manifest_reader_internal.cc:
##########
@@ -0,0 +1,244 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include "manifest_reader_internal.h"
+
+#include <array>
+
+#include <nanoarrow/nanoarrow.h>
+
+#include "iceberg/arrow_c_data_guard_internal.h"
+#include "iceberg/manifest_entry.h"
+#include "iceberg/manifest_list.h"
+#include "iceberg/schema.h"
+#include "iceberg/schema_internal.h"
+#include "iceberg/type.h"
+
+namespace iceberg {
+
+#define ARROW_RETURN_IF_NOT_OK(status, error)                      \
+  if (status != NANOARROW_OK) {                                    \

Review Comment:
   ```suggestion
     if (status != NANOARROW_OK) [[unlikely]] {                                 
   \
   ```



##########
src/iceberg/manifest_reader_internal.cc:
##########
@@ -0,0 +1,244 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include "manifest_reader_internal.h"
+
+#include <array>
+
+#include <nanoarrow/nanoarrow.h>
+
+#include "iceberg/arrow_c_data_guard_internal.h"
+#include "iceberg/manifest_entry.h"
+#include "iceberg/manifest_list.h"
+#include "iceberg/schema.h"
+#include "iceberg/schema_internal.h"
+#include "iceberg/type.h"
+
+namespace iceberg {
+
+#define ARROW_RETURN_IF_NOT_OK(status, error)                      \
+  if (status != NANOARROW_OK) {                                    \
+    return InvalidArrowData("NanoArrow error: {}", error.message); \
+  }
+
+Result<std::vector<std::unique_ptr<ManifestFile>>> ParseManifestListEntry(
+    ArrowSchema* schema, ArrowArray* array_in, const Schema& iceberg_schema) {
+  if (schema->n_children != array_in->n_children) {
+    return InvalidArgument("Columns size not match between schema:{} and 
array:{}",
+                           schema->n_children, array_in->n_children);
+  }
+  if (iceberg_schema.fields().size() != array_in->n_children) {
+    return InvalidArgument("Columns size not match between schema:{} and 
array:{}",
+                           iceberg_schema.fields().size(), 
array_in->n_children);
+  }
+
+  ArrowError error;
+  ArrowArrayView array_view;
+  auto status = ArrowArrayViewInitFromSchema(&array_view, schema, &error);
+  ARROW_RETURN_IF_NOT_OK(status, error);
+  internal::ArrowArrayViewGuard view_guard(&array_view);
+  status = ArrowArrayViewSetArray(&array_view, array_in, &error);
+  ARROW_RETURN_IF_NOT_OK(status, error);
+  status = ArrowArrayViewValidate(&array_view, 
NANOARROW_VALIDATION_LEVEL_FULL, &error);
+  ARROW_RETURN_IF_NOT_OK(status, error);
+
+  std::vector<std::unique_ptr<ManifestFile>> manifest_files;
+  manifest_files.resize(array_in->length);
+  for (auto& manifest_file : manifest_files) {
+    manifest_file = std::make_unique<ManifestFile>();
+  }
+
+  for (int64_t idx = 0; idx < array_in->n_children; idx++) {
+    const auto& field = iceberg_schema.GetFieldByIndex(idx);
+    if (!field.has_value()) {
+      return InvalidArgument("Field not found in schema: {}", idx);
+    }
+    auto field_name = field.value().get().name();
+    auto view_of_column = array_view.children[idx];
+
+#define PARSE_PRIMITIVE_FIELD(field_name, type)                           \
+  for (size_t row_idx = 0; row_idx < view_of_column->length; row_idx++) { \
+    if (!ArrowArrayViewIsNull(view_of_column, row_idx)) {                 \
+      auto value = ArrowArrayViewGetIntUnsafe(view_of_column, row_idx);   \
+      manifest_files[row_idx]->field_name = static_cast<type>(value);     \
+    }                                                                     \
+  }
+
+    if (field_name == ManifestFile::kManifestPath.name()) {
+      for (size_t row_idx = 0; row_idx < view_of_column->length; row_idx++) {
+        if (!ArrowArrayViewIsNull(view_of_column, row_idx)) {
+          auto value = ArrowArrayViewGetStringUnsafe(view_of_column, row_idx);
+          std::string path_str(value.data, value.size_bytes);
+          manifest_files[row_idx]->manifest_path = path_str;
+        }
+      }
+    } else if (field_name == ManifestFile::kManifestLength.name()) {
+      PARSE_PRIMITIVE_FIELD(manifest_length, int64_t);
+    } else if (field_name == ManifestFile::kPartitionSpecId.name()) {
+      PARSE_PRIMITIVE_FIELD(partition_spec_id, int32_t);
+    } else if (field_name == ManifestFile::kContent.name()) {
+      for (size_t row_idx = 0; row_idx < view_of_column->length; row_idx++) {
+        if (!ArrowArrayViewIsNull(view_of_column, row_idx)) {
+          auto value = ArrowArrayViewGetIntUnsafe(view_of_column, row_idx);
+          manifest_files[row_idx]->content = 
static_cast<ManifestFile::Content>(value);
+        }
+      }
+    } else if (field_name == ManifestFile::kSequenceNumber.name()) {
+      PARSE_PRIMITIVE_FIELD(sequence_number, int64_t);
+    } else if (field_name == ManifestFile::kMinSequenceNumber.name()) {
+      PARSE_PRIMITIVE_FIELD(min_sequence_number, int64_t);
+    } else if (field_name == ManifestFile::kAddedSnapshotId.name()) {
+      PARSE_PRIMITIVE_FIELD(added_snapshot_id, int64_t);
+    } else if (field_name == ManifestFile::kAddedFilesCount.name()) {
+      PARSE_PRIMITIVE_FIELD(added_files_count, int32_t);
+    } else if (field_name == ManifestFile::kExistingFilesCount.name()) {
+      PARSE_PRIMITIVE_FIELD(existing_files_count, int32_t);
+    } else if (field_name == ManifestFile::kDeletedFilesCount.name()) {
+      PARSE_PRIMITIVE_FIELD(deleted_files_count, int32_t);
+    } else if (field_name == ManifestFile::kAddedRowsCount.name()) {
+      PARSE_PRIMITIVE_FIELD(added_rows_count, int64_t);
+    } else if (field_name == ManifestFile::kExistingRowsCount.name()) {
+      PARSE_PRIMITIVE_FIELD(existing_rows_count, int64_t);
+    } else if (field_name == ManifestFile::kDeletedRowsCount.name()) {
+      PARSE_PRIMITIVE_FIELD(deleted_rows_count, int64_t);
+    } else if (field_name == ManifestFile::kPartitions.name()) {
+      // view_of_column is list<struct<PartitionFieldSummary>>
+      auto manifest_count = view_of_column->length;
+      if (view_of_column->storage_type != ArrowType::NANOARROW_TYPE_LIST) {
+        return InvalidArgument("partitions field should be a list.");
+      }
+      auto view_of_list_iterm = view_of_column->children[0];
+      // view_of_list_iterm is struct<PartitionFieldSummary>
+      if (view_of_list_iterm->storage_type != 
ArrowType::NANOARROW_TYPE_STRUCT) {
+        return InvalidArgument("partitions list field should be a list.");
+      }
+      if (view_of_list_iterm->n_children != 4) {
+        return InvalidArgument("PartitionFieldSummary should have 4 fields.");
+      }
+      if (view_of_list_iterm->children[0]->storage_type !=
+          ArrowType::NANOARROW_TYPE_BOOL) {
+        return InvalidArgument("contains_null should have be bool type 
column.");
+      }
+      auto contains_null = view_of_list_iterm->children[0];
+      if (view_of_list_iterm->children[1]->storage_type !=
+          ArrowType::NANOARROW_TYPE_BOOL) {
+        return InvalidArgument("contains_nan should have be bool type 
column.");
+      }
+      auto contains_nan = view_of_list_iterm->children[1];
+      if (view_of_list_iterm->children[2]->storage_type !=
+          ArrowType::NANOARROW_TYPE_BINARY) {
+        return InvalidArgument("lower_bound should have be binary type 
column.");
+      }
+      auto lower_bound_list = view_of_list_iterm->children[2];
+      if (view_of_list_iterm->children[3]->storage_type !=
+          ArrowType::NANOARROW_TYPE_BINARY) {
+        return InvalidArgument("upper_bound should have be binary type 
column.");
+      }
+      auto upper_bound_list = view_of_list_iterm->children[3];
+      for (int64_t manifest_idx = 0; manifest_idx < manifest_count; 
manifest_idx++) {
+        auto offset = ArrowArrayViewListChildOffset(view_of_column, 
manifest_idx);
+        auto next_offset =
+            ArrowArrayViewListChildOffset(view_of_column, manifest_idx + 1);
+        // partitions from offset to next_offset belongs to manifest_idx
+        auto& manifest_file = manifest_files[manifest_idx];
+        for (int64_t partition_idx = offset; partition_idx < next_offset;
+             partition_idx++) {
+          PartitionFieldSummary partition_field_summary;
+          if (!ArrowArrayViewIsNull(contains_null, partition_idx)) {
+            partition_field_summary.contains_null =
+                ArrowArrayViewGetIntUnsafe(contains_null, partition_idx);
+          }
+          if (!ArrowArrayViewIsNull(contains_nan, partition_idx)) {
+            partition_field_summary.contains_nan =
+                ArrowArrayViewGetIntUnsafe(contains_nan, partition_idx);
+          }
+          if (!ArrowArrayViewIsNull(lower_bound_list, partition_idx)) {
+            auto buffer = ArrowArrayViewGetBytesUnsafe(lower_bound_list, 
partition_idx);
+            partition_field_summary.lower_bound = std::vector<uint8_t>(
+                buffer.data.as_char, buffer.data.as_char + buffer.size_bytes);
+          }
+          if (!ArrowArrayViewIsNull(upper_bound_list, partition_idx)) {
+            auto buffer = ArrowArrayViewGetBytesUnsafe(upper_bound_list, 
partition_idx);
+            partition_field_summary.upper_bound = std::vector<uint8_t>(
+                buffer.data.as_char, buffer.data.as_char + buffer.size_bytes);
+          }
+
+          manifest_file->partitions.emplace_back(partition_field_summary);
+        }
+      }
+    } else if (field_name == ManifestFile::kKeyMetadata.name()) {
+      for (size_t row_idx = 0; row_idx < view_of_column->length; row_idx++) {
+        if (!ArrowArrayViewIsNull(view_of_column, row_idx)) {
+          auto buffer = ArrowArrayViewGetBytesUnsafe(view_of_column, row_idx);
+          manifest_files[row_idx]->key_metadata = std::vector<uint8_t>(
+              buffer.data.as_char, buffer.data.as_char + buffer.size_bytes);
+        }
+      }
+    } else if (field_name == ManifestFile::kFirstRowId.name()) {
+      PARSE_PRIMITIVE_FIELD(first_row_id, int64_t);
+    } else {
+      return InvalidArgument("Unsupported type: {}", field_name);
+    }
+  }
+#undef PARSE_PRIMITIVE_FIELD
+  return manifest_files;
+}  // namespace iceberg
+
+Result<std::vector<std::unique_ptr<ManifestEntry>>> 
ManifestReaderImpl::Entries() const {
+  return {};
+}
+
+Result<std::vector<std::unique_ptr<ManifestFile>>> 
ManifestListReaderImpl::Files() const {
+  std::vector<std::unique_ptr<ManifestFile>> manifest_files;
+  auto arrow_schema = reader_->Schema();
+  if (!arrow_schema.has_value()) {
+    return InvalidArgument("Get schema failed in reader:{}",
+                           arrow_schema.error().message);
+  }
+  internal::ArrowSchemaGuard schema_guard(&arrow_schema.value());
+  auto schema = FromArrowSchema(arrow_schema.value(), std::nullopt);

Review Comment:
   We should pass this schema explicitly when creating the reader instead of 
converting it back here.



##########
src/iceberg/manifest_reader_internal.cc:
##########
@@ -0,0 +1,244 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include "manifest_reader_internal.h"
+
+#include <array>
+
+#include <nanoarrow/nanoarrow.h>
+
+#include "iceberg/arrow_c_data_guard_internal.h"
+#include "iceberg/manifest_entry.h"
+#include "iceberg/manifest_list.h"
+#include "iceberg/schema.h"
+#include "iceberg/schema_internal.h"
+#include "iceberg/type.h"
+
+namespace iceberg {
+
+#define ARROW_RETURN_IF_NOT_OK(status, error)                      \
+  if (status != NANOARROW_OK) {                                    \
+    return InvalidArrowData("NanoArrow error: {}", error.message); \
+  }
+
+Result<std::vector<std::unique_ptr<ManifestFile>>> ParseManifestListEntry(
+    ArrowSchema* schema, ArrowArray* array_in, const Schema& iceberg_schema) {
+  if (schema->n_children != array_in->n_children) {
+    return InvalidArgument("Columns size not match between schema:{} and 
array:{}",
+                           schema->n_children, array_in->n_children);
+  }
+  if (iceberg_schema.fields().size() != array_in->n_children) {
+    return InvalidArgument("Columns size not match between schema:{} and 
array:{}",
+                           iceberg_schema.fields().size(), 
array_in->n_children);
+  }
+
+  ArrowError error;
+  ArrowArrayView array_view;
+  auto status = ArrowArrayViewInitFromSchema(&array_view, schema, &error);
+  ARROW_RETURN_IF_NOT_OK(status, error);
+  internal::ArrowArrayViewGuard view_guard(&array_view);
+  status = ArrowArrayViewSetArray(&array_view, array_in, &error);
+  ARROW_RETURN_IF_NOT_OK(status, error);
+  status = ArrowArrayViewValidate(&array_view, 
NANOARROW_VALIDATION_LEVEL_FULL, &error);
+  ARROW_RETURN_IF_NOT_OK(status, error);
+
+  std::vector<std::unique_ptr<ManifestFile>> manifest_files;
+  manifest_files.resize(array_in->length);
+  for (auto& manifest_file : manifest_files) {
+    manifest_file = std::make_unique<ManifestFile>();
+  }
+
+  for (int64_t idx = 0; idx < array_in->n_children; idx++) {
+    const auto& field = iceberg_schema.GetFieldByIndex(idx);
+    if (!field.has_value()) {
+      return InvalidArgument("Field not found in schema: {}", idx);
+    }
+    auto field_name = field.value().get().name();
+    auto view_of_column = array_view.children[idx];
+
+#define PARSE_PRIMITIVE_FIELD(field_name, type)                           \
+  for (size_t row_idx = 0; row_idx < view_of_column->length; row_idx++) { \
+    if (!ArrowArrayViewIsNull(view_of_column, row_idx)) {                 \
+      auto value = ArrowArrayViewGetIntUnsafe(view_of_column, row_idx);   \
+      manifest_files[row_idx]->field_name = static_cast<type>(value);     \
+    }                                                                     \
+  }
+
+    if (field_name == ManifestFile::kManifestPath.name()) {

Review Comment:
   The schemas to read from manifest list and manifest file are provided by the 
library so they are fixed. We can simply define a `map<string, size_t>` to find 
the index of a specific field_name.



##########
src/iceberg/manifest_reader_internal.cc:
##########
@@ -0,0 +1,244 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include "manifest_reader_internal.h"
+
+#include <array>
+
+#include <nanoarrow/nanoarrow.h>
+
+#include "iceberg/arrow_c_data_guard_internal.h"
+#include "iceberg/manifest_entry.h"
+#include "iceberg/manifest_list.h"
+#include "iceberg/schema.h"
+#include "iceberg/schema_internal.h"
+#include "iceberg/type.h"
+
+namespace iceberg {
+
+#define ARROW_RETURN_IF_NOT_OK(status, error)                      \
+  if (status != NANOARROW_OK) {                                    \
+    return InvalidArrowData("NanoArrow error: {}", error.message); \
+  }
+
+Result<std::vector<std::unique_ptr<ManifestFile>>> ParseManifestListEntry(
+    ArrowSchema* schema, ArrowArray* array_in, const Schema& iceberg_schema) {
+  if (schema->n_children != array_in->n_children) {
+    return InvalidArgument("Columns size not match between schema:{} and 
array:{}",
+                           schema->n_children, array_in->n_children);
+  }
+  if (iceberg_schema.fields().size() != array_in->n_children) {
+    return InvalidArgument("Columns size not match between schema:{} and 
array:{}",
+                           iceberg_schema.fields().size(), 
array_in->n_children);
+  }
+
+  ArrowError error;
+  ArrowArrayView array_view;
+  auto status = ArrowArrayViewInitFromSchema(&array_view, schema, &error);
+  ARROW_RETURN_IF_NOT_OK(status, error);
+  internal::ArrowArrayViewGuard view_guard(&array_view);
+  status = ArrowArrayViewSetArray(&array_view, array_in, &error);
+  ARROW_RETURN_IF_NOT_OK(status, error);
+  status = ArrowArrayViewValidate(&array_view, 
NANOARROW_VALIDATION_LEVEL_FULL, &error);
+  ARROW_RETURN_IF_NOT_OK(status, error);
+
+  std::vector<std::unique_ptr<ManifestFile>> manifest_files;
+  manifest_files.resize(array_in->length);
+  for (auto& manifest_file : manifest_files) {
+    manifest_file = std::make_unique<ManifestFile>();
+  }
+
+  for (int64_t idx = 0; idx < array_in->n_children; idx++) {
+    const auto& field = iceberg_schema.GetFieldByIndex(idx);
+    if (!field.has_value()) {
+      return InvalidArgument("Field not found in schema: {}", idx);
+    }
+    auto field_name = field.value().get().name();
+    auto view_of_column = array_view.children[idx];
+
+#define PARSE_PRIMITIVE_FIELD(field_name, type)                           \
+  for (size_t row_idx = 0; row_idx < view_of_column->length; row_idx++) { \
+    if (!ArrowArrayViewIsNull(view_of_column, row_idx)) {                 \
+      auto value = ArrowArrayViewGetIntUnsafe(view_of_column, row_idx);   \
+      manifest_files[row_idx]->field_name = static_cast<type>(value);     \
+    }                                                                     \
+  }
+
+    if (field_name == ManifestFile::kManifestPath.name()) {
+      for (size_t row_idx = 0; row_idx < view_of_column->length; row_idx++) {
+        if (!ArrowArrayViewIsNull(view_of_column, row_idx)) {
+          auto value = ArrowArrayViewGetStringUnsafe(view_of_column, row_idx);
+          std::string path_str(value.data, value.size_bytes);
+          manifest_files[row_idx]->manifest_path = path_str;
+        }
+      }
+    } else if (field_name == ManifestFile::kManifestLength.name()) {
+      PARSE_PRIMITIVE_FIELD(manifest_length, int64_t);
+    } else if (field_name == ManifestFile::kPartitionSpecId.name()) {
+      PARSE_PRIMITIVE_FIELD(partition_spec_id, int32_t);
+    } else if (field_name == ManifestFile::kContent.name()) {
+      for (size_t row_idx = 0; row_idx < view_of_column->length; row_idx++) {
+        if (!ArrowArrayViewIsNull(view_of_column, row_idx)) {
+          auto value = ArrowArrayViewGetIntUnsafe(view_of_column, row_idx);
+          manifest_files[row_idx]->content = 
static_cast<ManifestFile::Content>(value);
+        }
+      }
+    } else if (field_name == ManifestFile::kSequenceNumber.name()) {
+      PARSE_PRIMITIVE_FIELD(sequence_number, int64_t);
+    } else if (field_name == ManifestFile::kMinSequenceNumber.name()) {
+      PARSE_PRIMITIVE_FIELD(min_sequence_number, int64_t);
+    } else if (field_name == ManifestFile::kAddedSnapshotId.name()) {
+      PARSE_PRIMITIVE_FIELD(added_snapshot_id, int64_t);
+    } else if (field_name == ManifestFile::kAddedFilesCount.name()) {
+      PARSE_PRIMITIVE_FIELD(added_files_count, int32_t);
+    } else if (field_name == ManifestFile::kExistingFilesCount.name()) {
+      PARSE_PRIMITIVE_FIELD(existing_files_count, int32_t);
+    } else if (field_name == ManifestFile::kDeletedFilesCount.name()) {
+      PARSE_PRIMITIVE_FIELD(deleted_files_count, int32_t);
+    } else if (field_name == ManifestFile::kAddedRowsCount.name()) {
+      PARSE_PRIMITIVE_FIELD(added_rows_count, int64_t);
+    } else if (field_name == ManifestFile::kExistingRowsCount.name()) {
+      PARSE_PRIMITIVE_FIELD(existing_rows_count, int64_t);
+    } else if (field_name == ManifestFile::kDeletedRowsCount.name()) {
+      PARSE_PRIMITIVE_FIELD(deleted_rows_count, int64_t);
+    } else if (field_name == ManifestFile::kPartitions.name()) {
+      // view_of_column is list<struct<PartitionFieldSummary>>
+      auto manifest_count = view_of_column->length;
+      if (view_of_column->storage_type != ArrowType::NANOARROW_TYPE_LIST) {
+        return InvalidArgument("partitions field should be a list.");
+      }
+      auto view_of_list_iterm = view_of_column->children[0];
+      // view_of_list_iterm is struct<PartitionFieldSummary>
+      if (view_of_list_iterm->storage_type != 
ArrowType::NANOARROW_TYPE_STRUCT) {
+        return InvalidArgument("partitions list field should be a list.");
+      }
+      if (view_of_list_iterm->n_children != 4) {
+        return InvalidArgument("PartitionFieldSummary should have 4 fields.");
+      }
+      if (view_of_list_iterm->children[0]->storage_type !=
+          ArrowType::NANOARROW_TYPE_BOOL) {
+        return InvalidArgument("contains_null should have be bool type 
column.");
+      }
+      auto contains_null = view_of_list_iterm->children[0];
+      if (view_of_list_iterm->children[1]->storage_type !=
+          ArrowType::NANOARROW_TYPE_BOOL) {
+        return InvalidArgument("contains_nan should have be bool type 
column.");
+      }
+      auto contains_nan = view_of_list_iterm->children[1];
+      if (view_of_list_iterm->children[2]->storage_type !=
+          ArrowType::NANOARROW_TYPE_BINARY) {
+        return InvalidArgument("lower_bound should have be binary type 
column.");
+      }
+      auto lower_bound_list = view_of_list_iterm->children[2];
+      if (view_of_list_iterm->children[3]->storage_type !=
+          ArrowType::NANOARROW_TYPE_BINARY) {
+        return InvalidArgument("upper_bound should have be binary type 
column.");
+      }
+      auto upper_bound_list = view_of_list_iterm->children[3];
+      for (int64_t manifest_idx = 0; manifest_idx < manifest_count; 
manifest_idx++) {
+        auto offset = ArrowArrayViewListChildOffset(view_of_column, 
manifest_idx);
+        auto next_offset =
+            ArrowArrayViewListChildOffset(view_of_column, manifest_idx + 1);
+        // partitions from offset to next_offset belongs to manifest_idx
+        auto& manifest_file = manifest_files[manifest_idx];
+        for (int64_t partition_idx = offset; partition_idx < next_offset;
+             partition_idx++) {
+          PartitionFieldSummary partition_field_summary;
+          if (!ArrowArrayViewIsNull(contains_null, partition_idx)) {
+            partition_field_summary.contains_null =
+                ArrowArrayViewGetIntUnsafe(contains_null, partition_idx);
+          }
+          if (!ArrowArrayViewIsNull(contains_nan, partition_idx)) {
+            partition_field_summary.contains_nan =
+                ArrowArrayViewGetIntUnsafe(contains_nan, partition_idx);
+          }
+          if (!ArrowArrayViewIsNull(lower_bound_list, partition_idx)) {
+            auto buffer = ArrowArrayViewGetBytesUnsafe(lower_bound_list, 
partition_idx);
+            partition_field_summary.lower_bound = std::vector<uint8_t>(
+                buffer.data.as_char, buffer.data.as_char + buffer.size_bytes);
+          }
+          if (!ArrowArrayViewIsNull(upper_bound_list, partition_idx)) {
+            auto buffer = ArrowArrayViewGetBytesUnsafe(upper_bound_list, 
partition_idx);
+            partition_field_summary.upper_bound = std::vector<uint8_t>(
+                buffer.data.as_char, buffer.data.as_char + buffer.size_bytes);
+          }
+
+          manifest_file->partitions.emplace_back(partition_field_summary);
+        }
+      }
+    } else if (field_name == ManifestFile::kKeyMetadata.name()) {
+      for (size_t row_idx = 0; row_idx < view_of_column->length; row_idx++) {
+        if (!ArrowArrayViewIsNull(view_of_column, row_idx)) {
+          auto buffer = ArrowArrayViewGetBytesUnsafe(view_of_column, row_idx);
+          manifest_files[row_idx]->key_metadata = std::vector<uint8_t>(
+              buffer.data.as_char, buffer.data.as_char + buffer.size_bytes);
+        }
+      }
+    } else if (field_name == ManifestFile::kFirstRowId.name()) {
+      PARSE_PRIMITIVE_FIELD(first_row_id, int64_t);
+    } else {
+      return InvalidArgument("Unsupported type: {}", field_name);
+    }
+  }
+#undef PARSE_PRIMITIVE_FIELD
+  return manifest_files;
+}  // namespace iceberg
+
+Result<std::vector<std::unique_ptr<ManifestEntry>>> 
ManifestReaderImpl::Entries() const {
+  return {};
+}
+
+Result<std::vector<std::unique_ptr<ManifestFile>>> 
ManifestListReaderImpl::Files() const {
+  std::vector<std::unique_ptr<ManifestFile>> manifest_files;
+  auto arrow_schema = reader_->Schema();
+  if (!arrow_schema.has_value()) {
+    return InvalidArgument("Get schema failed in reader:{}",
+                           arrow_schema.error().message);
+  }

Review Comment:
   ```suggestion
     ICEBERG_ASSIGN_OR_RAISE(auto arrow_schema, reader_->Schema());
   ```
   
   nit: you may simply write the above



-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: [email protected]

For queries about this service, please contact Infrastructure at:
[email protected]


---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to