If an error occurred while setting up logback, the error message is n…

…ot now printed to the console

dropwizard-logging/src/main/java/io/dropwizard/logging/LoggingFactory.java

@@ -10,10 +10,11 @@
 import ch.qos.logback.core.ConsoleAppender;
 import com.codahale.metrics.MetricRegistry;
 import com.codahale.metrics.logback.InstrumentedAppender;
+import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonProperty;
+import com.google.common.annotations.VisibleForTesting;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
-import org.slf4j.ILoggerFactory;
 import org.slf4j.LoggerFactory;
 import org.slf4j.bridge.SLF4JBridgeHandler;
 
@@ -25,6 +26,9 @@
 import java.util.Map;
 import java.util.TimeZone;
 
+import static ch.qos.logback.core.util.StatusPrinter.printIfErrorsOccured;
+import static com.google.common.base.Preconditions.checkNotNull;
+
 public class LoggingFactory {
     // initially configure for WARN+ console logging
     public static void bootstrap() {
@@ -71,6 +75,18 @@ private static void hijackJDKLogging() {
             new ConsoleAppenderFactory()
     );
 
+    @JsonIgnore
+    private final LoggerContext loggerContext;
+
+    public LoggingFactory() {
+        this((LoggerContext) LoggerFactory.getILoggerFactory());
+    }
+
+    @VisibleForTesting
+    LoggingFactory(LoggerContext loggerContext) {
+        this.loggerContext = checkNotNull(loggerContext);
+    }
+
     @JsonProperty
     public Level getLevel() {
         return level;
@@ -110,6 +126,8 @@ public void configure(MetricRegistry metricRegistry, String name) {
             root.addAppender(output.build(root.getLoggerContext(), name, null));
         }
 
+        printIfErrorsOccured(root.getLoggerContext());
+
         final MBeanServer server = ManagementFactory.getPlatformMBeanServer();
         try {
             final ObjectName objectName = new ObjectName("io.dropwizard:type=Logging");
@@ -128,11 +146,7 @@ public void configure(MetricRegistry metricRegistry, String name) {
     }
 
     public void stop() {
-        ILoggerFactory loggerFactory = LoggerFactory.getILoggerFactory();
-        if (loggerFactory instanceof LoggerContext) {
-            LoggerContext context = (LoggerContext) loggerFactory;
-            context.stop();
-        }
+        loggerContext.stop();
     }
 
     private void configureInstrumentation(Logger root, MetricRegistry metricRegistry) {
@@ -143,7 +157,7 @@ private void configureInstrumentation(Logger root, MetricRegistry metricRegistry
     }
 
     private Logger configureLevels() {
-        final Logger root = (Logger) LoggerFactory.getLogger(org.slf4j.Logger.ROOT_LOGGER_NAME);
+        final Logger root = loggerContext.getLogger(org.slf4j.Logger.ROOT_LOGGER_NAME);
         root.getLoggerContext().reset();
 
         final LevelChangePropagator propagator = new LevelChangePropagator();
@@ -155,7 +169,7 @@ private Logger configureLevels() {
         root.setLevel(level);
 
         for (Map.Entry<String, Level> entry : loggers.entrySet()) {
-            ((Logger) LoggerFactory.getLogger(entry.getKey())).setLevel(entry.getValue());
+            loggerContext.getLogger(entry.getKey()).setLevel(entry.getValue());
         }
 
         return root;

dropwizard-logging/src/test/java/io/dropwizard/logging/LoggingFactoryPrintErrorMessagesTest.java

@@ -0,0 +1,93 @@
+package io.dropwizard.logging;
+
+import ch.qos.logback.classic.LoggerContext;
+import ch.qos.logback.core.util.StatusPrinter;
+import com.codahale.metrics.MetricRegistry;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.PrintStream;
+import java.io.UnsupportedEncodingException;
+import java.nio.charset.StandardCharsets;
+
+import static java.util.Collections.singletonList;
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class LoggingFactoryPrintErrorMessagesTest {
+
+    @Rule
+    public final TemporaryFolder tempDir = new TemporaryFolder();
+
+    File folderWithoutWritePermission;
+    File folderWithWritePermission;
+
+    LoggingFactory factory;
+    LoggerContext loggerContext;
+
+    @Before
+    public void setUp() throws Exception {
+        folderWithoutWritePermission = tempDir.newFolder("folder-without-write-permission");
+        folderWithoutWritePermission.setWritable(false);
+
+        folderWithWritePermission = tempDir.newFolder("folder-with-write-permission");
+
+        loggerContext = new LoggerContext();
+        factory = new LoggingFactory(loggerContext);
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        loggerContext.stop();
+    }
+
+    private void configureLoggingFactoryWithFileAppender(File file){
+        factory.setAppenders(singletonList(newFileAppenderFactory(file)));
+    }
+
+    private AppenderFactory newFileAppenderFactory(File file){
+        FileAppenderFactory fileAppenderFactory = new FileAppenderFactory();
+
+        fileAppenderFactory.setCurrentLogFilename(file.toString() + File.separator + "my-log-file.log");
+        fileAppenderFactory.setArchive(false);
+
+        return fileAppenderFactory;
+    }
+
+    private String configureAndCaptureSystemOut() throws UnsupportedEncodingException {
+        ByteArrayOutputStream out = new ByteArrayOutputStream();
+
+        try {
+            StatusPrinter.setPrintStream(new PrintStream(out));
+            factory.configure(new MetricRegistry(), "logger-test");
+        }finally {
+            StatusPrinter.setPrintStream(System.out);
+        }
+
+        return out.toString(StandardCharsets.UTF_8.name());
+    }
+
+    @Test
+    public void testWhenFileAppenderDoesNotHaveWritePermissionToFolder_PrintsErrorMessageToConsole() throws Exception {
+        File file = folderWithoutWritePermission;
+
+        configureLoggingFactoryWithFileAppender(file);
+
+        assertThat(file.canWrite()).isFalse();
+        assertThat(configureAndCaptureSystemOut()).contains(file.toString());
+    }
+
+    @Test
+    public void testWhenSettingUpLoggingWithValidConfiguration_NoErrorMessageIsPrintedToConsole() throws Exception {
+        File file = folderWithWritePermission;
+
+        configureLoggingFactoryWithFileAppender(file);
+
+        assertThat(file.canWrite()).isTrue();
+        assertThat(configureAndCaptureSystemOut()).isEmpty();
+    }
+}