Add support for Couchbase's role-based access

See gh-16389

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/couchbase/CouchbaseConfiguration.java

@@ -57,7 +57,14 @@ public class CouchbaseConfiguration {
 	@Bean
 	@Primary
 	public Cluster couchbaseCluster() {
-		return CouchbaseCluster.create(couchbaseEnvironment(), determineBootstrapHosts());
+		CouchbaseCluster couchbaseCluster = CouchbaseCluster
+				.create(couchbaseEnvironment(), determineBootstrapHosts());
+		if (this.properties.getUsername().isEmpty()
+				|| this.properties.getPassword().isEmpty()) {
+			return couchbaseCluster;
+		}
+		return couchbaseCluster.authenticate(this.properties.getUsername(),
+				this.properties.getPassword());
 	}
 
 	/**
@@ -79,9 +86,13 @@ public class CouchbaseConfiguration {
 	@Bean
 	@Primary
 	public Bucket couchbaseClient() {
+		if (this.properties.getUsername().isEmpty()
+				|| this.properties.getPassword().isEmpty()) {
 			return couchbaseCluster().openBucket(this.properties.getBucket().getName(),
 					this.properties.getBucket().getPassword());
 		}
+		return couchbaseCluster().openBucket(this.properties.getBucket().getName());
+	}
 
 	/**
 	 * Initialize an environment builder based on the specified settings.

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/couchbase/CouchbaseProperties.java

@@ -13,7 +13,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.springframework.boot.autoconfigure.couchbase;
 
 import java.time.Duration;
@@ -42,6 +41,16 @@ public class CouchbaseProperties {
 
 	private final Env env = new Env();
 
+	/**
+	 * Password of the cluster on RBA(role base access).
+	 */
+	private String password = "";
+
+	/**
+	 * Username of the cluster on RBA(role base access).
+	 */
+	private String username = "";
+
 	public List<String> getBootstrapHosts() {
 		return this.bootstrapHosts;
 	}
@@ -58,6 +67,22 @@ public class CouchbaseProperties {
 		return this.env;
 	}
 
+	public String getPassword() {
+		return this.password;
+	}
+
+	public void setPassword(String password) {
+		this.password = password;
+	}
+
+	public String getUsername() {
+		return this.username;
+	}
+
+	public void setUsername(String username) {
+		this.username = username;
+	}
+
 	public static class Bucket {
 
 		/**