Update for new APIs + slight bugfix

Author: pitrou

cpp/src/parquet/arrow/generate_fuzz_corpus.cc

@@ -174,32 +174,24 @@ std::vector<WriteConfig> GetEncryptedWriteConfigurations(const ::arrow::Schema&
         continue;
       }
       auto column_key = MakeEncryptionKey();
-      column_map[field->name()] = ColumnEncryptionProperties::Builder(field->name())
-                                      .key(column_key.key)
-                                      ->key_metadata(column_key.key_metadata)
-                                      ->build();
+      column_map[field->name()] = ColumnEncryptionProperties::WithColumnKey(
+          column_key.key, column_key.key_metadata);
     }
+    ARROW_DCHECK_NE(column_map.size(), 0);
     file_encryptions.push_back(
         file_encryption_builder().encrypted_columns(std::move(column_map))->build());
   }
-  // Mostly unencrypted columns
-  // (ideally we would like an encrypted footer and only plaintext columns, but the
-  // current API doesn't allow that)
+  // Unencrypted columns
   {
     ColumnPathToEncryptionPropertiesMap column_map;
     // Only encrypt the first non-nested column, the rest will be written in plaintext
     for (const auto& field : schema.fields()) {
-      if (field->type()->num_fields() == 0) {
-        auto column_key = MakeEncryptionKey();
-        column_map[field->name()] = ColumnEncryptionProperties::Builder(field->name())
-                                        .key(column_key.key)
-                                        ->key_metadata(column_key.key_metadata)
-                                        ->build();
-        break;
+      if (field->type()->num_fields() > 0) {
+        continue;
       }
+      column_map[field->name()] = ColumnEncryptionProperties::Unencrypted();
     }
-    ARROW_DCHECK_EQ(column_map.size(), 1);
-    ARROW_DCHECK_LT(column_map.size(), static_cast<size_t>(schema.num_fields()));
+    ARROW_DCHECK_NE(column_map.size(), 0);
     file_encryptions.push_back(
         file_encryption_builder().encrypted_columns(std::move(column_map))->build());
   }

cpp/src/parquet/encryption/encryption.cc

@@ -277,8 +277,7 @@ FileEncryptionProperties::Builder* FileEncryptionProperties::Builder::footer_key
 std::shared_ptr<ColumnEncryptionProperties>
 FileEncryptionProperties::column_encryption_properties(const std::string& column_path) {
   if (encrypted_columns_.size() == 0) {
-    auto builder = std::make_shared<ColumnEncryptionProperties::Builder>(column_path);
-    return builder->build();
+    return ColumnEncryptionProperties::WithFooterKey();
   }
   if (encrypted_columns_.find(column_path) != encrypted_columns_.end()) {
     return encrypted_columns_[column_path];

cpp/src/parquet/encryption/internal_file_encryptor.cc

@@ -99,7 +99,7 @@ InternalFileEncryptor::InternalFileEncryptor::GetColumnEncryptor(
     }
   }
   auto column_prop = properties_->column_encryption_properties(column_path);
-  if (column_prop == nullptr) {
+  if (column_prop == nullptr || !column_prop->is_encrypted()) {
     return nullptr;
   }
 

cpp/src/parquet/encryption/write_configurations_test.cc

@@ -104,6 +104,7 @@ TEST_F(TestEncryptionConfiguration, EncryptTwoColumnsAndTheFooter) {
       ColumnEncryptionProperties::WithColumnKey(kColumnEncryptionKey1_, "kc1");
   encryption_cols2[path_to_float_field_] =
       ColumnEncryptionProperties::WithColumnKey(kColumnEncryptionKey2_, "kc2");
+  encryption_cols2[kBooleanFieldName] = ColumnEncryptionProperties::Unencrypted();
 
   FileEncryptionProperties::Builder file_encryption_builder_2(kFooterEncryptionKey_);
 
@@ -122,6 +123,7 @@ TEST_F(TestEncryptionConfiguration, EncryptTwoColumnsWithPlaintextFooter) {
       ColumnEncryptionProperties::WithColumnKey(kColumnEncryptionKey1_, "kc1");
   encryption_cols3[path_to_float_field_] =
       ColumnEncryptionProperties::WithColumnKey(kColumnEncryptionKey2_, "kc2");
+  encryption_cols3[kBooleanFieldName] = ColumnEncryptionProperties::Unencrypted();
 
   FileEncryptionProperties::Builder file_encryption_builder_3(kFooterEncryptionKey_);
 
@@ -140,6 +142,7 @@ TEST_F(TestEncryptionConfiguration, EncryptTwoColumnsAndFooterWithAadPrefix) {
       ColumnEncryptionProperties::WithColumnKey(kColumnEncryptionKey1_, "kc1");
   encryption_cols4[path_to_float_field_] =
       ColumnEncryptionProperties::WithColumnKey(kColumnEncryptionKey2_, "kc2");
+  encryption_cols4[kBooleanFieldName] = ColumnEncryptionProperties::Unencrypted();
 
   FileEncryptionProperties::Builder file_encryption_builder_4(kFooterEncryptionKey_);
 
@@ -159,6 +162,7 @@ TEST_F(TestEncryptionConfiguration,
       ColumnEncryptionProperties::WithColumnKey(kColumnEncryptionKey1_, "kc1");
   encryption_cols5[path_to_float_field_] =
       ColumnEncryptionProperties::WithColumnKey(kColumnEncryptionKey2_, "kc2");
+  encryption_cols5[kBooleanFieldName] = ColumnEncryptionProperties::Unencrypted();
 
   FileEncryptionProperties::Builder file_encryption_builder_5(kFooterEncryptionKey_);
 
@@ -179,6 +183,7 @@ TEST_F(TestEncryptionConfiguration, EncryptTwoColumnsAndFooterUseAES_GCM_CTR) {
       ColumnEncryptionProperties::WithColumnKey(kColumnEncryptionKey1_, "kc1");
   encryption_cols6[path_to_float_field_] =
       ColumnEncryptionProperties::WithColumnKey(kColumnEncryptionKey2_, "kc2");
+  encryption_cols6[kBooleanFieldName] = ColumnEncryptionProperties::Unencrypted();
 
   FileEncryptionProperties::Builder file_encryption_builder_6(kFooterEncryptionKey_);