fix: dry run NPE when there is no query parameters (#2899)

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Author: obada-ab

google-cloud-bigquery/src/main/java/com/google/cloud/bigquery/ConnectionImpl.java

@@ -55,6 +55,7 @@
 import java.io.IOException;
 import java.util.AbstractList;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.LinkedList;
 import java.util.List;
@@ -173,7 +174,9 @@ public BigQueryDryRunResult dryRun(String sql) throws BigQuerySQLException {
  List<QueryParameter> queryParametersPb =
  dryRunJob.getStatistics().getQuery().getUndeclaredQueryParameters();
  List<Parameter> queryParameters =
- Lists.transform(queryParametersPb, QUERY_PARAMETER_FROM_PB_FUNCTION);
+ queryParametersPb == null
+ ? Collections.emptyList()
+ : Lists.transform(queryParametersPb, QUERY_PARAMETER_FROM_PB_FUNCTION);
  QueryStatistics queryStatistics = JobStatistics.fromPb(dryRunJob);
  SessionInfo sessionInfo =
  queryStatistics.getSessionInfo() == null ? null : queryStatistics.getSessionInfo();

google-cloud-bigquery/src/test/java/com/google/cloud/bigquery/ConnectionImplTest.java

@@ -237,6 +237,34 @@ public void testQueryDryRun() throws BigQuerySQLException {
  .createJobForQuery(any(com.google.api.services.bigquery.model.Job.class));
  }
 
+ @Test
+ public void testQueryDryRunNoQueryParameters() throws BigQuerySQLException {
+ com.google.api.services.bigquery.model.JobStatistics2 queryMock =
+ new com.google.api.services.bigquery.model.JobStatistics2()
+ .setSchema(FAST_QUERY_TABLESCHEMA);
+ com.google.api.services.bigquery.model.JobStatistics jobStatsMock =
+ new com.google.api.services.bigquery.model.JobStatistics()
+ .setCreationTime(1234L)
+ .setStartTime(5678L)
+ .setQuery(queryMock);
+ com.google.api.services.bigquery.model.JobConfigurationQuery jobConfigurationQuery =
+ new com.google.api.services.bigquery.model.JobConfigurationQuery();
+ com.google.api.services.bigquery.model.JobConfiguration jobConfig =
+ new com.google.api.services.bigquery.model.JobConfiguration()
+ .setQuery(jobConfigurationQuery);
+ com.google.api.services.bigquery.model.Job mockDryRunJob =
+ new com.google.api.services.bigquery.model.Job()
+ .setStatistics(jobStatsMock)
+ .setConfiguration(jobConfig);
+ when(bigqueryRpcMock.createJobForQuery(any(com.google.api.services.bigquery.model.Job.class)))
+ .thenReturn(mockDryRunJob);
+ BigQueryDryRunResult dryRunResult = connection.dryRun(DRY_RUN_SQL);
+ assertEquals(0, dryRunResult.getQueryParameters().size());
+ assertEquals(QUERY_SCHEMA, dryRunResult.getSchema());
+ verify(bigqueryRpcMock, times(1))
+ .createJobForQuery(any(com.google.api.services.bigquery.model.Job.class));
+ }
+
  @Test
  public void testParseDataTask() throws InterruptedException {
  BlockingQueue<Tuple<Iterable<FieldValueList>, Boolean>> pageCache =

google-cloud-bigquery/src/test/java/com/google/cloud/bigquery/it/ITBigQueryTest.java

@@ -2989,6 +2989,34 @@ public void testConnectionImplDryRun() throws SQLException {
  assertEquals(StatementType.SELECT, queryStatistics.getStatementType());
  }
 
+ @Test
+ public void testConnectionImplDryRunNoQueryParameters() throws SQLException {
+ String query =
+ String.format(
+ "select StringField, BigNumericField, BooleanField, BytesField, IntegerField, "
+ + "TimestampField, FloatField, NumericField, TimeField, DateField, DateTimeField, "
+ + "GeographyField, RecordField.BytesField, RecordField.BooleanField, "
+ + "IntegerArrayField from %s order by TimestampField",
+ TABLE_ID_FASTQUERY_BQ_RESULTSET.getTable());
+ ConnectionSettings connectionSettings =
+ ConnectionSettings.newBuilder()
+ .setDefaultDataset(DatasetId.of(DATASET))
+ .setCreateSession(true)
+ .build();
+ Connection connection = bigquery.createConnection(connectionSettings);
+ BigQueryDryRunResult bigQueryDryRunResultSet = connection.dryRun(query);
+ assertNotNull(bigQueryDryRunResultSet.getSchema());
+ assertEquals(
+ BQ_RESULTSET_EXPECTED_SCHEMA, bigQueryDryRunResultSet.getSchema()); // match the schema
+ List<Parameter> queryParameters = bigQueryDryRunResultSet.getQueryParameters();
+ assertEquals(0, queryParameters.size());
+ QueryStatistics queryStatistics = bigQueryDryRunResultSet.getStatistics().getQueryStatistics();
+ assertNotNull(queryStatistics);
+ SessionInfo sessionInfo = bigQueryDryRunResultSet.getStatistics().getSessionInfo();
+ assertNotNull(sessionInfo.getSessionId());
+ assertEquals(StatementType.SELECT, queryStatistics.getStatementType());
+ }
+
  @Test
  // This test case test the order of the records, making sure that the result is not jumbled up due
  // to the multithreaded BigQueryResult implementation