Fix properties configuration support for per-logger properties

log4j-core-test/src/test/java/org/apache/logging/log4j/core/config/properties/PropertiesConfigurationTest.java

@@ -34,6 +34,7 @@
 import org.apache.logging.log4j.core.LoggerContext;
 import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.LoggerConfig;
+import org.apache.logging.log4j.core.config.Property;
 import org.apache.logging.log4j.core.filter.ThresholdFilter;
 import org.apache.logging.log4j.core.test.appender.ListAppender;
 import org.apache.logging.log4j.core.test.junit.LoggerContextSource;
@@ -56,6 +57,21 @@ void testPropertiesConfiguration(final Configuration config) {
         final Filter filter = config.getFilter();
         assertNotNull(filter, "No Filter");
         assertInstanceOf(ThresholdFilter.class, filter, "Not a Threshold Filter");
+
+        final List<Property> rootProperties = config.getRootLogger().getPropertyList();
+        assertNotNull(rootProperties, "Root properties list should not be null");
+        assertEquals(1, rootProperties.size());
+        assertEquals("client.address", rootProperties.get(0).getName());
+        assertEquals("${web:request.remoteAddress}", rootProperties.get(0).getValue());
+
+        final LoggerConfig log4jLogger = loggers.get("org.apache.logging.log4j");
+        assertNotNull(log4jLogger, "org.apache.logging.log4j logger should not be null");
+        final List<Property> log4jProperties = log4jLogger.getPropertyList();
+        assertNotNull(log4jProperties, "org.apache.logging.log4j properties list should not be null");
+        assertEquals(1, log4jProperties.size());
+        assertEquals("subsystem", log4jProperties.get(0).getName());
+        assertEquals("Database", log4jProperties.get(0).getValue());
+
         final Logger logger = LogManager.getLogger(getClass());
         logger.info("Welcome to Log4j!");
     }

log4j-core-test/src/test/resources/log4j2-properties.properties

@@ -38,3 +38,11 @@ logger.log4j.additivity = false
 
 rootLogger.appenderRef.console.ref = StdOut
 rootLogger.level = ERROR
+
+rootLogger.property.type = Property
+rootLogger.property.name = client.address
+rootLogger.property.value = $${web:request.remoteAddress}
+
+logger.log4j.property.type = Property
+logger.log4j.property.name = subsystem
+logger.log4j.property.value = Database

log4j-core/src/main/java/org/apache/logging/log4j/core/config/properties/PropertiesConfigurationBuilder.java

@@ -312,8 +312,9 @@ private LoggerComponentBuilder createLogger(final String key, final Properties p
         }
         if (levelAndRefs != null) {
             loggerBuilder.addAttribute("levelAndRefs", levelAndRefs);
+            properties.remove("");
         }
-        return loggerBuilder;
+        return processRemainingProperties(loggerBuilder, properties);
     }
 
     private RootLoggerComponentBuilder createRootLogger(final Properties properties) {
@@ -343,8 +344,10 @@ private RootLoggerComponentBuilder createRootLogger(final Properties properties)
         addLoggersToComponent(loggerBuilder, properties);
         if (levelAndRefs != null) {
             loggerBuilder.addAttribute("levelAndRefs", levelAndRefs);
+            properties.remove("");
         }
-        return addFiltersToComponent(loggerBuilder, properties);
+        addFiltersToComponent(loggerBuilder, properties);
+        return processRemainingProperties(loggerBuilder, properties);
     }
 
     private LayoutComponentBuilder createLayout(final String appenderName, final Properties properties) {

src/changelog/.2.x.x/4024_fix_roperties_configuration_support_for_logger_properties.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<entry xmlns="https://logging.apache.org/xml/ns"
+       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+       xsi:schemaLocation="
+           https://logging.apache.org/xml/ns
+           https://logging.apache.org/xml/ns/log4j-changelog-0.xsd"
+       type="changed">
+    <issue id="4024" link="https://github.com/apache/logging-log4j2/issues/4024"/>
+    <issue id="4142" link="https://github.com/apache/logging-log4j2/pull/4142"/>
+    <description format="asciidoc">
+        Fix properties configuration format to correctly parse and apply nested custom properties on loggers and root loggers
+    </description>
+</entry>