From d665441ca955418d2456408d5483144f35ef6825 Mon Sep 17 00:00:00 2001
From: Phillip Webb <pwebb@vmware.com>
Date: Wed, 12 Oct 2022 11:17:09 -0700
Subject: [PATCH] Polish 'Add Spring Environment to LoggerContext'

See gh-32731
---
 .../logging/log4j2/Log4J2LoggingSystem.java    | 18 ++++++++++++++----
 .../log4j2/Log4J2LoggingSystemTests.java       | 10 ++++++++++
 2 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/log4j2/Log4J2LoggingSystem.java b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/log4j2/Log4J2LoggingSystem.java
index d36a6d0f439..b1ec7c67a13 100644
--- a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/log4j2/Log4J2LoggingSystem.java
+++ b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/log4j2/Log4J2LoggingSystem.java
@@ -58,6 +58,7 @@ import org.springframework.boot.logging.LoggerConfiguration;
 import org.springframework.boot.logging.LoggingInitializationContext;
 import org.springframework.boot.logging.LoggingSystem;
 import org.springframework.boot.logging.LoggingSystemFactory;
+import org.springframework.core.Conventions;
 import org.springframework.core.Ordered;
 import org.springframework.core.annotation.Order;
 import org.springframework.core.env.Environment;
@@ -85,10 +86,8 @@ public class Log4J2LoggingSystem extends AbstractLoggingSystem {
 
 	private static final String LOG4J_LOG_MANAGER = "org.apache.logging.log4j.jul.LogManager";
 
-	/**
-	 * Identifies the Spring environment.
-	 */
-	public static final String ENVIRONMENT_KEY = "SpringEnvironment";
+	static final String ENVIRONMENT_KEY = Conventions.getQualifiedAttributeName(Log4J2LoggingSystem.class,
+			"environment");
 
 	private static final LogLevels<Level> LEVELS = new LogLevels<>();
 
@@ -475,6 +474,17 @@ public class Log4J2LoggingSystem extends AbstractLoggingSystem {
 		loggerContext.setExternalContext(null);
 	}
 
+	/**
+	 * Get the Spring {@link Environment} attached to the given {@link LoggerContext} or
+	 * {@code null} if no environment is available.
+	 * @param loggerContext the logger context
+	 * @return the Spring {@link Environment} or {@code null}
+	 * @since 3.0.0
+	 */
+	public static Environment getEnvironment(LoggerContext loggerContext) {
+		return (Environment) ((loggerContext != null) ? loggerContext.getObject(ENVIRONMENT_KEY) : null);
+	}
+
 	/**
 	 * {@link LoggingSystemFactory} that returns {@link Log4J2LoggingSystem} if possible.
 	 */
diff --git a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/logging/log4j2/Log4J2LoggingSystemTests.java b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/logging/log4j2/Log4J2LoggingSystemTests.java
index 6045e50a3f3..3155bf13f84 100644
--- a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/logging/log4j2/Log4J2LoggingSystemTests.java
+++ b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/logging/log4j2/Log4J2LoggingSystemTests.java
@@ -57,6 +57,7 @@ import org.springframework.boot.testsupport.classpath.ClassPathExclusions;
 import org.springframework.boot.testsupport.logging.ConfigureClasspathToPreferLog4j2;
 import org.springframework.boot.testsupport.system.CapturedOutput;
 import org.springframework.boot.testsupport.system.OutputCaptureExtension;
+import org.springframework.core.env.Environment;
 import org.springframework.mock.env.MockEnvironment;
 import org.springframework.util.ClassUtils;
 import org.springframework.util.StringUtils;
@@ -438,6 +439,15 @@ class Log4J2LoggingSystemTests extends AbstractLoggingSystemTests {
 		assertThat(this.loggingSystem.getConfiguration()).isInstanceOf(CompositeConfiguration.class);
 	}
 
+	@Test
+	void initializeAttachesEnvironmentToLoggerContext() {
+		this.loggingSystem.beforeInitialize();
+		this.loggingSystem.initialize(this.initializationContext, null, null);
+		LoggerContext loggerContext = (LoggerContext) LogManager.getContext(false);
+		Environment environment = Log4J2LoggingSystem.getEnvironment(loggerContext);
+		assertThat(environment).isSameAs(this.environment);
+	}
+
 	private String getRelativeClasspathLocation(String fileName) {
 		String defaultPath = ClassUtils.getPackageName(getClass());
 		defaultPath = defaultPath.replace('.', '/');