lang/java/avro/src/test/java/org/apache/avro/TestSchemaWarnings.java

/*
 * 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
 *
 *     https://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.avro;

import org.junit.AfterClass;
import org.junit.Before;
import org.junit.Test;

import java.io.ByteArrayOutputStream;
import java.io.PrintStream;
import java.nio.charset.StandardCharsets;

import static org.apache.avro.LogicalType.LOGICAL_TYPE_PROP;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.containsString;
import static org.hamcrest.Matchers.is;
import static org.hamcrest.Matchers.nullValue;

public class TestSchemaWarnings {

  private final static PrintStream originalErr = System.err;

  /**
   * The capturable replacement for the system err stream.
   */
  private final ByteArrayOutputStream capturedErr = new ByteArrayOutputStream();

  @Before
  public void setupStdErr() {
    capturedErr.reset();
    System.setErr(new PrintStream(capturedErr));
  }

  @AfterClass
  public static void restoreStdErr() {
    System.setErr(originalErr);
  }

  public String getCapturedStdErr() {
    System.out.flush();
    String stderr = new String(capturedErr.toByteArray(), StandardCharsets.UTF_8);
    capturedErr.reset();
    return stderr;
  }

  @Test
  public void testWarnWhenTheLogicalTypeIsOnTheField() {
    // A record with a single int field.
    Schema s = SchemaBuilder.record("A").fields().requiredInt("a1").endRecord();

    // Force reparsing the schema, and no warning should be logged.
    s = new Schema.Parser().parse(s.toString());
    assertThat(s.getField("a1").schema().getLogicalType(), nullValue());
    assertThat(getCapturedStdErr(), is(""));

    // Add the logical type annotation to the field (as opposed to the field schema)
    // and parse it again. This is a common error, see AVRO-3014, AVRO-2015.
    s.getField("a1").addProp(LOGICAL_TYPE_PROP, LogicalTypes.date().getName());
    assertThat(s.getField("a1").schema().getLogicalType(), nullValue());

    // Force reparsing the schema, and a warning should be logged.
    s = new Schema.Parser().parse(s.toString());
    assertThat(getCapturedStdErr(), containsString("Ignored the A.a1.logicalType property (\"date\"). It should"
        + " probably be nested inside the \"type\" for the field."));
    assertThat(s.getField("a1").schema().getLogicalType(), nullValue());

    // Add the logical type annotation to the field schema. This doesn't change the
    // logical type of an already parsed schema.
    s.getField("a1").schema().addProp(LOGICAL_TYPE_PROP, LogicalTypes.date().getName());
    assertThat(s.getField("a1").schema().getLogicalType(), nullValue());

    // Force reparsing the schema. No warning should be logged, and the logical type
    // should be applied.
    s = new Schema.Parser().parse(s.toString());
    assertThat(getCapturedStdErr(), is(""));
    assertThat(s.getField("a1").schema().getLogicalType(), is(LogicalTypes.date()));

  }

  @Test
  public void testWarnWhenTheLogicalTypeIsIgnored() {
    // A record with a single int field.
    Schema s = SchemaBuilder.record("A").fields().requiredLong("a1").endRecord();

    // Add the logical type annotation to the field (as opposed to the field schema)
    // and parse it again.
    s.getField("a1").schema().addProp(LOGICAL_TYPE_PROP, LogicalTypes.date().getName());
    // Force reparsing the schema. No warning should be logged, and the logical type
    // should be applied.
    s = new Schema.Parser().parse(s.toString());
    assertThat(s.getField("a1").schema().getLogicalType(), nullValue());
    assertThat(getCapturedStdErr(), containsString("Ignoring invalid logical type for name: date"));
  }
}