Map MinIdle and MaxValidationTime to R2DBC pools

Closes gh-34724

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/r2dbc/ConnectionFactoryConfigurations.java

@@ -103,6 +103,8 @@ abstract class ConnectionFactoryConfigurations {
 				map.from(pool.getMaxSize()).to(builder::maxSize);
 				map.from(pool.getValidationQuery()).whenHasText().to(builder::validationQuery);
 				map.from(pool.getValidationDepth()).to(builder::validationDepth);
+				map.from(pool.getMinIdle()).to(builder::minIdle);
+				map.from(pool.getMaxValidationTime()).to(builder::maxValidationTime);
 				return new ConnectionPool(builder.build());
 			}
 

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/r2dbc/R2dbcProperties.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2021 the original author or authors.
+ * Copyright 2012-2023 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.
@@ -136,6 +136,13 @@ public class R2dbcProperties {
 
 	public static class Pool {
 
+		/**
+		 * Minimal number of idle connections.
+		 *
+		 * @since 2.7.12
+		 */
+		private int minIdle = 0;
+
 		/**
 		 * Maximum amount of time that a connection is allowed to sit idle in the pool.
 		 */
@@ -153,6 +160,14 @@ public class R2dbcProperties {
 		 */
 		private Duration maxAcquireTime;
 
+		/**
+		 * Maximum time to validate a connection from the pool. By default, wait
+		 * indefinitely.
+		 *
+		 * @since 2.7.12
+		 */
+		private Duration maxValidationTime;
+
 		/**
 		 * Maximum time to wait to create a new connection. By default, wait indefinitely.
 		 */
@@ -183,6 +198,14 @@ public class R2dbcProperties {
 		 */
 		private boolean enabled = true;
 
+		public int getMinIdle() {
+			return this.minIdle;
+		}
+
+		public void setMinIdle(int minIdle) {
+			this.minIdle = minIdle;
+		}
+
 		public Duration getMaxIdleTime() {
 			return this.maxIdleTime;
 		}
@@ -199,6 +222,14 @@ public class R2dbcProperties {
 			this.maxLifeTime = maxLifeTime;
 		}
 
+		public Duration getMaxValidationTime() {
+			return this.maxValidationTime;
+		}
+
+		public void setMaxValidationTime(Duration maxValidationTime) {
+			this.maxValidationTime = maxValidationTime;
+		}
+
 		public Duration getMaxAcquireTime() {
 			return this.maxAcquireTime;
 		}

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/r2dbc/R2dbcAutoConfigurationTests.java

@@ -77,15 +77,25 @@ class R2dbcAutoConfigurationTests {
 	void configureWithUrlAndPoolPropertiesApplyProperties() {
 		this.contextRunner
 			.withPropertyValues("spring.r2dbc.url:r2dbc:h2:mem:///" + randomDatabaseName(),
-					"spring.r2dbc.pool.max-size=15", "spring.r2dbc.pool.max-acquire-time=3m")
+					"spring.r2dbc.pool.max-size=15", "spring.r2dbc.pool.max-acquire-time=3m",
+					"spring.r2dbc.pool.min-idle=1", "spring.r2dbc.pool.max-validation-time=1s",
+					"spring.r2dbc.pool.initial-size=0")
 			.run((context) -> {
 				assertThat(context).hasSingleBean(ConnectionFactory.class)
 					.hasSingleBean(ConnectionPool.class)
 					.hasSingleBean(R2dbcProperties.class);
 				ConnectionPool connectionPool = context.getBean(ConnectionPool.class);
-				PoolMetrics poolMetrics = connectionPool.getMetrics().get();
-				assertThat(poolMetrics.getMaxAllocatedSize()).isEqualTo(15);
-				assertThat(connectionPool).hasFieldOrPropertyWithValue("maxAcquireTime", Duration.ofMinutes(3));
+				connectionPool.warmup().block();
+				try {
+					PoolMetrics poolMetrics = connectionPool.getMetrics().get();
+					assertThat(poolMetrics.idleSize()).isEqualTo(1);
+					assertThat(poolMetrics.getMaxAllocatedSize()).isEqualTo(15);
+					assertThat(connectionPool).hasFieldOrPropertyWithValue("maxAcquireTime", Duration.ofMinutes(3));
+					assertThat(connectionPool).hasFieldOrPropertyWithValue("maxValidationTime", Duration.ofSeconds(1));
+				}
+				finally {
+					connectionPool.close().block();
+				}
 			});
 	}