Full stack regression for structured logging

src/test/java/org/apache/logging/log4j/core/layout/LambdaJsonLayoutTest.java

@@ -0,0 +1,72 @@
+package org.apache.logging.log4j.core.layout;
+
+import java.io.IOException;
+import java.nio.channels.FileChannel;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.nio.file.StandardOpenOption;
+import java.util.Map;
+import java.util.stream.Stream;
+
+import com.amazonaws.services.lambda.runtime.Context;
+import com.amazonaws.services.lambda.runtime.RequestHandler;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.mockito.Mock;
+import software.amazon.lambda.handlers.PowerLogToolEnabled;
+
+import static java.util.Collections.emptyMap;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
+import static org.mockito.Mockito.when;
+import static org.mockito.MockitoAnnotations.initMocks;
+
+class LambdaJsonLayoutTest {
+
+    private RequestHandler<Object, Object> handler = new PowerLogToolEnabled();
+
+    @Mock
+    private Context context;
+
+    @BeforeEach
+    void setUp() throws IOException {
+        initMocks(this);
+        setupContext();
+        //Make sure file is cleaned up before running full stack logging regression
+        FileChannel.open(Paths.get("target/logfile.json"), StandardOpenOption.WRITE).truncate(0).close();
+    }
+
+    @Test
+    void shouldLogInStructuredFormat() throws IOException {
+        handler.handleRequest("test", context);
+
+        assertThat(Files.lines(Paths.get("target/logfile.json")))
+                .hasSize(1)
+                .allSatisfy(line -> assertThat(parseToMap(line))
+                        .containsEntry("functionName", "testFunction")
+                        .containsEntry("functionVersion", "1")
+                        .containsEntry("functionMemorySize", "10")
+                        .containsEntry("functionArn", "testArn")
+                        .containsKey("timestamp")
+                        .containsKey("message")
+                        .containsKey("service"));
+    }
+
+    private Map<String, Object> parseToMap(String stringAsJson) {
+        try {
+            return new ObjectMapper().readValue(stringAsJson, Map.class);
+        } catch (JsonProcessingException e) {
+            fail("Failed parsing logger line " + stringAsJson);
+            return emptyMap();
+        }
+    }
+
+    private void setupContext() {
+        when(context.getFunctionName()).thenReturn("testFunction");
+        when(context.getInvokedFunctionArn()).thenReturn("testArn");
+        when(context.getFunctionVersion()).thenReturn("1");
+        when(context.getMemoryLimitInMB()).thenReturn(10);
+    }
+}

src/test/java/software/amazon/lambda/handlers/PowerLogToolEnabled.java

@@ -2,13 +2,17 @@
 
 import com.amazonaws.services.lambda.runtime.Context;
 import com.amazonaws.services.lambda.runtime.RequestHandler;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 import software.amazon.lambda.logging.PowerToolsLogging;
 
 public class PowerLogToolEnabled implements RequestHandler<Object, Object> {
+    private final Logger LOG = LogManager.getLogger(PowerToolLogEventEnabled.class);
 
     @Override
     @PowerToolsLogging
     public Object handleRequest(Object input, Context context) {
+        LOG.info("Test event");
         return null;
     }
 

src/test/resources/log4j2.xml

@@ -1,9 +1,9 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Configuration packages="com.amazonaws.services.lambda.runtime.log4j2">
     <Appenders>
-        <Console name="JsonAppender" target="SYSTEM_OUT">
+        <File name="JsonAppender" fileName="target/logfile.json">
             <LambdaJsonLayout compact="true" eventEol="true"/>
-        </Console>
+        </File>
     </Appenders>
     <Loggers>
         <Logger name="JsonLogger" level="INFO" additivity="false">