Change Logback's maxHistory property default to 7 days

Closes gh-15875

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/logback/DefaultLogbackConfiguration.java

@@ -61,6 +61,8 @@ class DefaultLogbackConfiguration {
 
 	private static final DataSize MAX_FILE_SIZE = DataSize.ofMegabytes(10);
 
+	private static final Integer MAX_FILE_HISTORY = 7;
+
 	private final PropertyResolver patterns;
 
 	private final LogFile logFile;
@@ -148,7 +150,7 @@ class DefaultLogbackConfiguration {
 		setMaxFileSize(rollingPolicy,
 				getDataSize("logging.file.max-size", MAX_FILE_SIZE));
 		rollingPolicy.setMaxHistory(this.patterns.getProperty("logging.file.max-history",
-				Integer.class, CoreConstants.UNBOUND_HISTORY));
+				Integer.class, MAX_FILE_HISTORY));
 		DataSize totalSizeCap = getDataSize("logging.file.total-size-cap",
 				DataSize.ofBytes(CoreConstants.UNBOUNDED_TOTAL_SIZE_CAP));
 		rollingPolicy.setTotalSizeCap(new FileSize(totalSizeCap.toBytes()));

spring-boot-project/spring-boot/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -107,7 +107,7 @@
       "type": "java.lang.Integer",
       "description": "Maximum of archive log files to keep. Only supported with the default logback setup.",
       "sourceType": "org.springframework.boot.context.logging.LoggingApplicationListener",
-      "defaultValue": 0
+      "defaultValue": 7
     },
     {
       "name": "logging.file.total-size-cap",

spring-boot-project/spring-boot/src/main/resources/org/springframework/boot/logging/logback/file-appender.xml

@@ -16,7 +16,7 @@ initialization performed by Boot
 			<cleanHistoryOnStart>${LOG_FILE_CLEAN_HISTORY_ON_START:-false}</cleanHistoryOnStart>
 			<fileNamePattern>${LOG_FILE}.%d{yyyy-MM-dd}.%i.gz</fileNamePattern>
 			<maxFileSize>${LOG_FILE_MAX_SIZE:-10MB}</maxFileSize>
-			<maxHistory>${LOG_FILE_MAX_HISTORY:-0}</maxHistory>
+			<maxHistory>${LOG_FILE_MAX_HISTORY:-7}</maxHistory>
 			<totalSizeCap>${LOG_FILE_TOTAL_SIZE_CAP:-0}</totalSizeCap>
 		</rollingPolicy>
 	</appender>

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/logging/logback/LogbackLoggingSystemTests.java

@@ -27,7 +27,6 @@ import ch.qos.logback.classic.Logger;
 import ch.qos.logback.classic.LoggerContext;
 import ch.qos.logback.classic.spi.LoggerContextListener;
 import ch.qos.logback.core.ConsoleAppender;
-import ch.qos.logback.core.CoreConstants;
 import ch.qos.logback.core.rolling.RollingFileAppender;
 import ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy;
 import org.hamcrest.Matcher;
@@ -134,8 +133,7 @@ public class LogbackLoggingSystemTests extends AbstractLoggingSystemTests {
 		assertThat(getLineWithText(file, "Hello world")).contains("INFO");
 		assertThat(ReflectionTestUtils.getField(getRollingPolicy(), "maxFileSize")
 				.toString()).isEqualTo("10 MB");
-		assertThat(getRollingPolicy().getMaxHistory())
-				.isEqualTo(CoreConstants.UNBOUND_HISTORY);
+		assertThat(getRollingPolicy().getMaxHistory()).isEqualTo(7);
 	}
 
 	@Test