Set the version to 'unknown' when redis_version is missing

See gh-48320

Signed-off-by: Huang Xiao <youngledo@qq.com>

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/data/redis/RedisHealth.java

@@ -34,7 +34,7 @@ final class RedisHealth {
 	}
 
 	static Builder up(Health.Builder builder, Properties info) {
-		builder.withDetail("version", info.getProperty("redis_version"));
+		builder.withDetail("version", info.getProperty("redis_version", "unknown"));
 		return builder.up();
 	}
 

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/redis/RedisHealthIndicatorTests.java

@@ -62,6 +62,19 @@ class RedisHealthIndicatorTests {
 		assertThat(health.getDetails()).containsEntry("version", "2.8.9");
 	}
 
+	@Test
+	void redisIsUpWithMissingVersion() {
+		Properties info = new Properties();
+		RedisConnection redisConnection = mock(RedisConnection.class);
+		RedisServerCommands serverCommands = mock(RedisServerCommands.class);
+		given(redisConnection.serverCommands()).willReturn(serverCommands);
+		given(serverCommands.info()).willReturn(info);
+		RedisHealthIndicator healthIndicator = createHealthIndicator(redisConnection);
+		Health health = healthIndicator.health();
+		assertThat(health.getStatus()).isEqualTo(Status.UP);
+		assertThat(health.getDetails()).containsEntry("version", "unknown");
+	}
+
 	@Test
 	void redisIsDown() {
 		RedisConnection redisConnection = mock(RedisConnection.class);

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/redis/RedisReactiveHealthIndicatorTests.java

@@ -68,6 +68,23 @@ class RedisReactiveHealthIndicatorTests {
 		then(redisConnection).should().closeLater();
 	}
 
+	@Test
+	void redisIsUpWithMissingVersion() {
+		Properties info = new Properties();
+		ReactiveRedisConnection redisConnection = mock(ReactiveRedisConnection.class);
+		given(redisConnection.closeLater()).willReturn(Mono.empty());
+		ReactiveServerCommands commands = mock(ReactiveServerCommands.class);
+		given(commands.info("server")).willReturn(Mono.just(info));
+		RedisReactiveHealthIndicator healthIndicator = createHealthIndicator(redisConnection, commands);
+		Mono<Health> health = healthIndicator.health();
+		StepVerifier.create(health).consumeNextWith((h) -> {
+			assertThat(h.getStatus()).isEqualTo(Status.UP);
+			assertThat(h.getDetails()).containsOnlyKeys("version");
+			assertThat(h.getDetails()).containsEntry("version", "unknown");
+		}).expectComplete().verify(Duration.ofSeconds(30));
+		then(redisConnection).should().closeLater();
+	}
+
 	@Test
 	void healthWhenClusterStateIsAbsentShouldBeUp() {
 		ReactiveRedisConnectionFactory redisConnectionFactory = createClusterConnectionFactory(null);