Configure password-based authentication with Cassandra

This commit updates the Cassandra auto-configuration to configure
password-based authentication on the CqlSession directly.

Closes gh-21487

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/cassandra/CassandraAutoConfiguration.java

@@ -80,12 +80,19 @@ public class CassandraAutoConfiguration {
 	public CqlSessionBuilder cassandraSessionBuilder(CassandraProperties properties,
 			DriverConfigLoader driverConfigLoader, ObjectProvider<CqlSessionBuilderCustomizer> builderCustomizers) {
 		CqlSessionBuilder builder = CqlSession.builder().withConfigLoader(driverConfigLoader);
+		configureAuthentication(properties, builder);
 		configureSsl(properties, builder);
 		builder.withKeyspace(properties.getKeyspaceName());
 		builderCustomizers.orderedStream().forEach((customizer) -> customizer.customize(builder));
 		return builder;
 	}
 
+	private void configureAuthentication(CassandraProperties properties, CqlSessionBuilder builder) {
+		if (properties.getUsername() != null) {
+			builder.withAuthCredentials(properties.getUsername(), properties.getPassword());
+		}
+	}
+
 	private void configureSsl(CassandraProperties properties, CqlSessionBuilder builder) {
 		if (properties.isSsl()) {
 			try {

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/cassandra/CassandraAutoConfigurationWithPasswordAuthenticationIntegrationTests.java

@@ -0,0 +1,91 @@
+/*
+ * Copyright 2012-2020 the original author or authors.
+ *
+ * Licensed 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.springframework.boot.autoconfigure.cassandra;
+
+import java.nio.charset.StandardCharsets;
+import java.time.Duration;
+
+import com.datastax.oss.driver.api.core.ConsistencyLevel;
+import com.datastax.oss.driver.api.core.CqlSession;
+import com.datastax.oss.driver.api.core.cql.SimpleStatement;
+import org.junit.jupiter.api.Test;
+import org.testcontainers.containers.CassandraContainer;
+import org.testcontainers.images.builder.Transferable;
+import org.testcontainers.junit.jupiter.Container;
+import org.testcontainers.junit.jupiter.Testcontainers;
+
+import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.test.context.runner.ApplicationContextRunner;
+import org.springframework.util.StreamUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+/**
+ * Tests for {@link CassandraAutoConfiguration} that only uses password authentication.
+ *
+ * @author Stephane Nicoll
+ */
+@Testcontainers(disabledWithoutDocker = true)
+class CassandraAutoConfigurationWithPasswordAuthenticationIntegrationTests {
+
+	@Container
+	static final CassandraContainer<?> cassandra = new PasswordAuthenticatorCassandraContainer().withStartupAttempts(5)
+			.withStartupTimeout(Duration.ofMinutes(10));
+
+	private final ApplicationContextRunner contextRunner = new ApplicationContextRunner()
+			.withConfiguration(AutoConfigurations.of(CassandraAutoConfiguration.class)).withPropertyValues(
+					"spring.data.cassandra.contact-points:" + cassandra.getHost() + ":"
+							+ cassandra.getFirstMappedPort(),
+					"spring.data.cassandra.local-datacenter=datacenter1", "spring.data.cassandra.read-timeout=20s",
+					"spring.data.cassandra.connect-timeout=10s");
+
+	@Test
+	void authenticationWithValidUsernameAndPassword() {
+		this.contextRunner.withPropertyValues("spring.data.cassandra.username=cassandra",
+				"spring.data.cassandra.password=cassandra").run((context) -> {
+					SimpleStatement select = SimpleStatement.newInstance("SELECT release_version FROM system.local")
+							.setConsistencyLevel(ConsistencyLevel.LOCAL_ONE);
+					assertThat(context.getBean(CqlSession.class).execute(select).one()).isNotNull();
+				});
+	}
+
+	@Test
+	void authenticationWithInvalidCredentials() {
+		this.contextRunner
+				.withPropertyValues("spring.data.cassandra.username=not-a-user",
+						"spring.data.cassandra.password=invalid-password")
+				.run((context) -> assertThatThrownBy(() -> context.getBean(CqlSession.class))
+						.hasMessageContaining("Authentication error"));
+	}
+
+	static final class PasswordAuthenticatorCassandraContainer
+			extends CassandraContainer<PasswordAuthenticatorCassandraContainer> {
+
+		@Override
+		protected void containerIsCreated(String containerId) {
+			String config = this.copyFileFromContainer("/etc/cassandra/cassandra.yaml",
+					(stream) -> StreamUtils.copyToString(stream, StandardCharsets.UTF_8));
+			String updatedConfig = config.replace("authenticator: AllowAllAuthenticator",
+					"authenticator: PasswordAuthenticator");
+			this.copyFileToContainer(Transferable.of(updatedConfig.getBytes(StandardCharsets.UTF_8)),
+					"/etc/cassandra/cassandra.yaml");
+		}
+
+	}
+
+}