[bq] improve tests coverage

spring-batch-bigquery/src/main/java/org/springframework/batch/extensions/bigquery/writer/BigQueryBaseItemWriter.java

@@ -123,8 +123,7 @@ public void write(final Chunk<? extends T> chunk) throws Exception {
                 this.logger.debug(String.format("Mapping %d elements", items.size()));
             }
 
-            final ByteBuffer byteBuffer = mapDataToBigQueryFormat(items);
-            doWriteDataToBigQuery(byteBuffer);
+            doWriteDataToBigQuery(mapDataToBigQueryFormat(items));
         }
     }
 

spring-batch-bigquery/src/main/java/org/springframework/batch/extensions/bigquery/writer/BigQueryCsvItemWriter.java

@@ -63,15 +63,6 @@ protected synchronized void doInitializeProperties(List<? extends T> items) {
         }
     }
 
-    /**
-     * Row mapper which transforms single BigQuery row into a desired type.
-     *
-     * @param rowMapper your row mapper
-     */
-    public void setRowMapper(Converter<T, byte[]> rowMapper) {
-        this.rowMapper = rowMapper;
-    }
-
     @Override
     protected List<byte[]> convertObjectsToByteArrays(List<? extends T> items) {
         return items
@@ -105,6 +96,15 @@ protected void performFormatSpecificChecks() {
 
     }
 
+    /**
+     * Row mapper which transforms single BigQuery row into a desired type.
+     *
+     * @param rowMapper your row mapper
+     */
+    public void setRowMapper(Converter<T, byte[]> rowMapper) {
+        this.rowMapper = rowMapper;
+    }
+
     private byte[] mapItemToCsv(T t) {
         try {
             return rowMapper == null ? objectWriter.writeValueAsBytes(t) : rowMapper.convert(t);

spring-batch-bigquery/src/main/java/org/springframework/batch/extensions/bigquery/writer/BigQueryJsonItemWriter.java

@@ -46,15 +46,6 @@ protected void doInitializeProperties(List<? extends T> items) {
         // Unused
     }
 
-    /**
-     * Converter that transforms a single row into a {@link String}.
-     *
-     * @param marshaller your JSON mapper
-     */
-    public void setMarshaller(JsonObjectMarshaller<T> marshaller) {
-        this.marshaller = marshaller;
-    }
-
     @Override
     protected List<byte[]> convertObjectsToByteArrays(List<? extends T> items) {
         return items
@@ -91,6 +82,15 @@ protected void performFormatSpecificChecks() {
         Assert.isTrue(Objects.equals(format, super.writeChannelConfig.getFormat()), "Only %s format is allowed".formatted(format));
     }
 
+    /**
+     * Converter that transforms a single row into a {@link String}.
+     *
+     * @param marshaller your JSON mapper
+     */
+    public void setMarshaller(JsonObjectMarshaller<T> marshaller) {
+        this.marshaller = marshaller;
+    }
+
     /**
      * BigQuery uses <a href="https://github.com/ndjson/ndjson-spec">ndjson</a>.
      * It is expected that to pass here JSON line generated by

spring-batch-bigquery/src/test/java/org/springframework/batch/extensions/bigquery/unit/writer/BigQueryBaseItemWriterTest.java

@@ -24,6 +24,7 @@
 import org.springframework.batch.extensions.bigquery.common.TestConstants;
 import org.springframework.batch.extensions.bigquery.unit.base.AbstractBigQueryTest;
 import org.springframework.batch.extensions.bigquery.writer.BigQueryBaseItemWriter;
+import org.springframework.batch.extensions.bigquery.writer.BigQueryItemWriterException;
 
 import java.lang.invoke.MethodHandles;
 import java.nio.ByteBuffer;
@@ -144,6 +145,46 @@ void testWrite() throws Exception {
         Mockito.verifyNoMoreInteractions(channel);
     }
 
+    @Test
+    void testWrite_Exception() throws Exception {
+        MethodHandles.Lookup handle = MethodHandles.privateLookupIn(BigQueryBaseItemWriter.class, MethodHandles.lookup());
+        AtomicBoolean consumerCalled = new AtomicBoolean();
+
+        Job job = Mockito.mock(Job.class);
+        Mockito.when(job.getJobId()).thenReturn(JobId.newBuilder().build());
+
+        TableDataWriteChannel channel = Mockito.mock(TableDataWriteChannel.class);
+        Mockito.when(channel.getJob()).thenReturn(job);
+        Mockito.when(channel.write(Mockito.any(ByteBuffer.class))).thenThrow(BigQueryException.class);
+
+        BigQuery bigQuery = prepareMockedBigQuery();
+        Mockito.when(bigQuery.writer(Mockito.any(WriteChannelConfiguration.class))).thenReturn(channel);
+
+        TestWriter writer = new TestWriter();
+        writer.setBigQuery(bigQuery);
+        writer.setJobConsumer(j -> consumerCalled.set(true));
+        writer.setWriteChannelConfig(WriteChannelConfiguration.of(TABLE_ID));
+
+        BigQueryItemWriterException actual = Assertions.assertThrows(BigQueryItemWriterException.class, () -> writer.write(TestConstants.CHUNK));
+        Assertions.assertEquals("Error on write happened", actual.getMessage());
+
+        AtomicLong actualCounter = (AtomicLong) handle
+                .findVarHandle(BigQueryBaseItemWriter.class, "bigQueryWriteCounter", AtomicLong.class)
+                .get(writer);
+
+        boolean writeFailed = (Boolean) handle
+                .findVarHandle(BigQueryBaseItemWriter.class, "writeFailed", boolean.class)
+                .get(writer);
+
+        Assertions.assertEquals(0L, actualCounter.get());
+        Assertions.assertTrue(writeFailed);
+        Assertions.assertFalse(consumerCalled.get());
+
+        Mockito.verify(channel).write(Mockito.any(ByteBuffer.class));
+        Mockito.verify(channel).close();
+        Mockito.verifyNoMoreInteractions(channel);
+    }
+
     @Test
     void testBaseAfterPropertiesSet_Exception() {
         TestWriter writer = new TestWriter();

spring-batch-bigquery/src/test/java/org/springframework/batch/extensions/bigquery/unit/writer/BigQueryCsvItemWriterTest.java

@@ -16,8 +16,10 @@
 
 package org.springframework.batch.extensions.bigquery.unit.writer;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectWriter;
 import com.fasterxml.jackson.dataformat.csv.CsvFactory;
+import com.fasterxml.jackson.dataformat.csv.CsvMapper;
 import com.google.cloud.bigquery.BigQuery;
 import com.google.cloud.bigquery.Field;
 import com.google.cloud.bigquery.FormatOptions;
@@ -83,14 +85,38 @@ void testSetRowMapper() throws IllegalAccessException, NoSuchFieldException {
     @Test
     void testConvertObjectsToByteArrays() {
         TestWriter writer = new TestWriter();
+        List<PersonDto> items = TestConstants.CHUNK.getItems();
 
         // Empty
         Assertions.assertTrue(writer.testConvert(List.of()).isEmpty());
 
-        // Not empty
+        // Not empty (row mapper)
         writer.setRowMapper(source -> source.toString().getBytes());
-        List<byte[]> actual = writer.testConvert(TestConstants.CHUNK.getItems());
-        List<byte[]> expected = TestConstants.CHUNK.getItems().stream().map(PersonDto::toString).map(String::getBytes).toList();
+        List<byte[]> actual = writer.testConvert(items);
+        List<byte[]> expected = items.stream().map(PersonDto::toString).map(String::getBytes).toList();
+        Assertions.assertEquals(expected.size(), actual.size());
+
+        for (int i = 0; i < actual.size(); i++) {
+            Assertions.assertArrayEquals(expected.get(i), actual.get(i));
+        }
+
+        // Not empty (object writer)
+        ObjectWriter csvWriter = new CsvMapper().writerWithTypedSchemaFor(PersonDto.class);
+        writer.setRowMapper(null);
+        writer.testInitializeProperties(items);
+        actual = writer.testConvert(items);
+
+        expected = items
+                .stream()
+                .map(pd -> {
+                    try {
+                        return csvWriter.writeValueAsBytes(pd);
+                    } catch (JsonProcessingException e) {
+                        throw new RuntimeException(e);
+                    }
+                })
+                .toList();
+
         Assertions.assertEquals(expected.size(), actual.size());
 
         for (int i = 0; i < actual.size(); i++) {