GH-3792: Bind parquet fields to Avro names before aliases

parquet-avro/src/main/java/org/apache/parquet/avro/AvroIndexedRecordConverter.java

@@ -126,16 +126,18 @@ private static <T> Class<T> getDatumClass(GenericData model, Schema schema) {
 
   private Schema.Field getAvroField(String parquetFieldName) {
     Schema.Field avroField = avroSchema.getField(parquetFieldName);
+    if (avroField != null) {
+      return avroField;
+    }
+
     for (Schema.Field f : avroSchema.getFields()) {
       if (f.aliases().contains(parquetFieldName)) {
         return f;
       }
     }
-    if (avroField == null) {
-      throw new InvalidRecordException(
-          String.format("Parquet/Avro schema mismatch. Avro field '%s' not found.", parquetFieldName));
-    }
-    return avroField;
+
+    throw new InvalidRecordException(
+        String.format("Parquet/Avro schema mismatch. Avro field '%s' not found.", parquetFieldName));
   }
 
   private static Converter newConverter(Schema schema, Type type, GenericData model, ParentValueContainer setter) {

parquet-avro/src/test/java/org/apache/parquet/avro/TestAvroFieldNameAndAlias.java

@@ -0,0 +1,74 @@
+/*
+ * 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.
+ */
+package org.apache.parquet.avro;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import org.apache.avro.Schema;
+import org.apache.avro.generic.GenericData;
+import org.apache.avro.generic.GenericRecord;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.Path;
+import org.apache.parquet.hadoop.ParquetReader;
+import org.junit.jupiter.api.io.TempDir;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+public class TestAvroFieldNameAndAlias {
+
+  @TempDir
+  private java.nio.file.Path tempDir;
+
+  @ParameterizedTest
+  @ValueSource(booleans = {false, true})
+  public void exactFieldNameTakesPrecedenceOverAlias(boolean compat) throws IOException {
+    Schema writerSchema = AvroTestUtil.record("Car", AvroTestUtil.field("make", Schema.create(Schema.Type.STRING)));
+    GenericRecord written = AvroTestUtil.instance(writerSchema, "make", "Volkswagen");
+    File file = AvroTestUtil.write(tempDir, GenericData.get(), writerSchema, written);
+
+    Configuration conf = new Configuration(false);
+    conf.setBoolean(AvroReadSupport.AVRO_COMPATIBILITY, compat);
+
+    // File has only "make". The reader still has a "make" field, plus an earlier
+    // "brand" field that aliases "make". An alias-first lookup writes the parquet
+    // value into brand and leaves make as its default.
+    Schema.Field brand = new Schema.Field("brand", Schema.create(Schema.Type.STRING), null, "unmapped-brand");
+    brand.addAlias("make");
+    Schema.Field make = new Schema.Field("make", Schema.create(Schema.Type.STRING), null, "unmapped-make");
+    Schema readerSchema = AvroTestUtil.record("Car", brand, make);
+    assertThat(readerSchema.getField("make")).isNotNull();
+    assertThat(readerSchema.getField("brand").aliases()).contains("make");
+
+    AvroReadSupport.setAvroReadSchema(conf, readerSchema);
+
+    List<GenericRecord> records = new ArrayList<>();
+    try (ParquetReader<GenericRecord> reader = new AvroParquetReader<>(conf, new Path(file.toString()))) {
+      records.add(reader.read());
+    }
+
+    assertThat(records).hasSize(1);
+    GenericRecord read = records.get(0);
+    assertThat(read.get("make")).asString().isEqualTo("Volkswagen");
+    assertThat(read.get("brand")).asString().isEqualTo("unmapped-brand");
+  }
+}