Polish 'Support Log4J2 string lookups from the Spring Environment'

See gh-32732

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/log4j2/SpringEnvironmentLookup.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2012-2022 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.logging.log4j2;
+
+import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.LoggerContext;
+import org.apache.logging.log4j.core.config.LoggerContextAware;
+import org.apache.logging.log4j.core.config.plugins.Plugin;
+import org.apache.logging.log4j.core.lookup.StrLookup;
+
+import org.springframework.core.env.Environment;
+import org.springframework.util.Assert;
+
+/**
+ * Lookup for Spring properties.
+ *
+ * @author Ralph Goers
+ * @author Phillip Webb
+ */
+@Plugin(name = "spring", category = StrLookup.CATEGORY)
+class SpringEnvironmentLookup implements LoggerContextAware, StrLookup {
+
+	private volatile Environment environment;
+
+	@Override
+	public String lookup(LogEvent event, String key) {
+		return lookup(key);
+	}
+
+	@Override
+	public String lookup(String key) {
+		Assert.state(this.environment != null, "Unable to obtain Spring Environment from LoggerContext");
+		return (this.environment != null) ? this.environment.getProperty(key) : null;
+	}
+
+	@Override
+	public void setLoggerContext(LoggerContext loggerContext) {
+		this.environment = Log4J2LoggingSystem.getEnvironment(loggerContext);
+	}
+
+}

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/log4j2/SpringLookup.java

@@ -1,112 +0,0 @@
-/*
- * Copyright 2012-2022 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.
- * You may obtain a copy of the License at
- *
- *      https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.springframework.boot.logging.log4j2;
-
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
-
-import org.apache.logging.log4j.Logger;
-import org.apache.logging.log4j.core.LogEvent;
-import org.apache.logging.log4j.core.LoggerContext;
-import org.apache.logging.log4j.core.config.LoggerContextAware;
-import org.apache.logging.log4j.core.config.plugins.Plugin;
-import org.apache.logging.log4j.core.lookup.StrLookup;
-import org.apache.logging.log4j.status.StatusLogger;
-
-import org.springframework.core.env.Environment;
-
-/**
- * Lookup for Spring properties.
- *
- * @author Ralph Goers
- * @since 3.0.0
- */
-@Plugin(name = "spring", category = StrLookup.CATEGORY)
-public class SpringLookup implements LoggerContextAware, StrLookup {
-
-	private static final Logger LOGGER = StatusLogger.getLogger();
-
-	private static final String ACTIVE = "profiles.active";
-
-	private static final String DEFAULT = "profiles.default";
-
-	private static final String PATTERN = "\\[(\\d+?)\\]";
-
-	private static final Pattern ACTIVE_PATTERN = Pattern.compile(ACTIVE + PATTERN);
-
-	private static final Pattern DEFAULT_PATTERN = Pattern.compile(DEFAULT + PATTERN);
-
-	private volatile Environment environment;
-
-	@Override
-	public String lookup(String key) {
-		if (this.environment == null) {
-			return null;
-		}
-		String lowerKey = key.toLowerCase();
-		if (lowerKey.startsWith(ACTIVE)) {
-			return doMatch(ACTIVE_PATTERN, key, this.environment.getActiveProfiles());
-		}
-		else if (lowerKey.startsWith(DEFAULT)) {
-			return doMatch(DEFAULT_PATTERN, key, this.environment.getDefaultProfiles());
-		}
-
-		return this.environment.getProperty(key);
-	}
-
-	private String doMatch(Pattern pattern, String key, String[] profiles) {
-		if (profiles.length == 0) {
-			return null;
-		}
-		if (profiles.length == 1) {
-			return profiles[0];
-		}
-		Matcher matcher = pattern.matcher(key);
-		if (matcher.matches()) {
-			try {
-				int index = Integer.parseInt(matcher.group(1));
-				if (index < profiles.length) {
-					return profiles[index];
-				}
-				LOGGER.warn("Index out of bounds for Spring default profiles: {}", index);
-				return null;
-			}
-			catch (Exception ex) {
-				LOGGER.warn("Unable to parse {} as integer value", matcher.group(1));
-				return null;
-			}
-
-		}
-		return String.join(",", profiles);
-	}
-
-	@Override
-	public String lookup(LogEvent event, String key) {
-		return lookup((key));
-	}
-
-	@Override
-	public void setLoggerContext(final LoggerContext loggerContext) {
-		if (loggerContext != null) {
-			this.environment = (Environment) loggerContext.getObject(Log4J2LoggingSystem.ENVIRONMENT_KEY);
-		}
-		else {
-			LOGGER.warn("Attempt to set LoggerContext reference to null in SpringLookup");
-		}
-	}
-
-}

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/logging/log4j2/SpringEnvironmentLookupTests.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2012-2022 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.logging.log4j2;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.core.LoggerContext;
+import org.apache.logging.log4j.core.lookup.Interpolator;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.mock.env.MockEnvironment;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
+
+/**
+ * Tests for {@link SpringEnvironmentLookup}.
+ *
+ * @author Phillip Webb
+ */
+class SpringEnvironmentLookupTests {
+
+	private MockEnvironment environment;
+
+	private LoggerContext loggerContext;
+
+	@BeforeEach
+	void setup() {
+		this.environment = new MockEnvironment();
+		this.loggerContext = (LoggerContext) LogManager.getContext(false);
+		this.loggerContext.putObject(Log4J2LoggingSystem.ENVIRONMENT_KEY, this.environment);
+	}
+
+	@AfterEach
+	void cleanup() {
+		this.loggerContext.removeObject(Log4J2LoggingSystem.ENVIRONMENT_KEY);
+	}
+
+	@Test
+	void lookupWhenFoundInEnvironmentReturnsValue() {
+		this.environment.setProperty("test", "test");
+		Interpolator lookup = createLookup(this.loggerContext);
+		assertThat(lookup.lookup("spring:test")).isEqualTo("test");
+	}
+
+	@Test
+	void lookupWhenNotFoundInEnvironmentReturnsNull() {
+		Interpolator lookup = createLookup(this.loggerContext);
+		assertThat(lookup.lookup("spring:test")).isNull();
+	}
+
+	@Test
+	void lookupWhenNoSpringEnvironmentThrowsException() {
+		this.loggerContext.removeObject(Log4J2LoggingSystem.ENVIRONMENT_KEY);
+		Interpolator lookup = createLookup(this.loggerContext);
+		assertThatIllegalStateException().isThrownBy(() -> assertThat(lookup.lookup("spring:test")).isEqualTo("test"))
+				.withMessage("Unable to obtain Spring Environment from LoggerContext");
+	}
+
+	private Interpolator createLookup(LoggerContext context) {
+		Interpolator lookup = new Interpolator();
+		lookup.setConfiguration(context.getConfiguration());
+		lookup.setLoggerContext(context);
+		return lookup;
+	}
+
+}