Polish "Use ssl.enabled flag when RabbitMQ address has no protocol"

There is a direct link between the sslEnabled flag and the default port
that should be used by an address. The checks are currently set in two
places:

* Determine which port should be used
* Determine if SSL should be enabled

This commit polishes the initial proposal so that secureConnection is
only set if a protocol is available.

See gh-19109

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/amqp/RabbitProperties.java

@@ -378,7 +378,7 @@ public class RabbitProperties {
 				return isEnabled();
 			}
 			Address address = RabbitProperties.this.parsedAddresses.get(0);
-			return address.secureConnection;
+			return address.determineSslEnabled(isEnabled());
 		}
 
 		public void setEnabled(boolean enabled) {
@@ -966,27 +966,25 @@ public class RabbitProperties {
 
 		private String virtualHost;
 
-		private boolean secureConnection;
+		private Boolean secureConnection;
 
 		private Address(String input, boolean sslEnabled) {
 			input = input.trim();
-			input = trimPrefix(input, sslEnabled);
+			input = trimPrefix(input);
 			input = parseUsernameAndPassword(input);
 			input = parseVirtualHost(input);
-			parseHostAndPort(input);
+			parseHostAndPort(input, sslEnabled);
 		}
 
-		private String trimPrefix(String input, boolean sslEnabled) {
+		private String trimPrefix(String input) {
 			if (input.startsWith(PREFIX_AMQP_SECURE)) {
 				this.secureConnection = true;
 				return input.substring(PREFIX_AMQP_SECURE.length());
 			}
 			if (input.startsWith(PREFIX_AMQP)) {
+				this.secureConnection = false;
 				return input.substring(PREFIX_AMQP.length());
 			}
-			if (sslEnabled) {
-				this.secureConnection = true;
-			}
 			return input;
 		}
 
@@ -1016,11 +1014,11 @@ public class RabbitProperties {
 			return input;
 		}
 
-		private void parseHostAndPort(String input) {
+		private void parseHostAndPort(String input, boolean sslEnabled) {
 			int portIndex = input.indexOf(':');
 			if (portIndex == -1) {
 				this.host = input;
-				this.port = (this.secureConnection) ? DEFAULT_PORT_SECURE : DEFAULT_PORT;
+				this.port = (determineSslEnabled(sslEnabled)) ? DEFAULT_PORT_SECURE : DEFAULT_PORT;
 			}
 			else {
 				this.host = input.substring(0, portIndex);
@@ -1028,6 +1026,10 @@ public class RabbitProperties {
 			}
 		}
 
+		private boolean determineSslEnabled(boolean sslEnabled) {
+			return (this.secureConnection != null) ? this.secureConnection : sslEnabled;
+		}
+
 	}
 
 }

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/amqp/RabbitPropertiesTests.java

@@ -101,13 +101,6 @@ public class RabbitPropertiesTests {
 		assertThat(this.properties.determinePort()).isEqualTo(5671);
 	}
 
-	@Test
-	public void determinePortReturnsDefaultAmqpsPortWhenFirstAddressHasNoExplicitPort() {
-		this.properties.setPort(1234);
-		this.properties.setAddresses("rabbit1.example.com,rabbit2.example.com:2345");
-		assertThat(this.properties.determinePort()).isEqualTo(5672);
-	}
-
 	@Test
 	public void determinePortReturnsDefaultAmqpsPortWhenFirstAddressHasNoExplicitPortButSslEnabled() {
 		this.properties.getSsl().setEnabled(true);
@@ -256,14 +249,14 @@ public class RabbitPropertiesTests {
 	}
 
 	@Test
-	public void determineSslUsingAddressWithoutAmpqsDefersToSslFlagProperty() {
+	public void sslDetermineEnabledIsTrueWhenAddressHasNoProtocolAndSslIsEnabled() {
 		this.properties.getSsl().setEnabled(true);
 		this.properties.setAddresses("root:password@otherhost");
 		assertThat(this.properties.getSsl().determineEnabled()).isTrue();
 	}
 
 	@Test
-	public void determineSslUsingAddressWithoutAmpqDefersToSslFlagProperty() {
+	public void sslDetermineEnabledIsFalseWhenAddressHasNoProtocolAndSslIsDisabled() {
 		this.properties.getSsl().setEnabled(false);
 		this.properties.setAddresses("root:password@otherhost");
 		assertThat(this.properties.getSsl().determineEnabled()).isFalse();