Java – the dropwizard does not record custom recorders to files

I have a dropwizard application. I configure the logger appender as a file, as shown below:

logging:
  level: INFO

  loggers:
    "mylogger": INFO
    "com.path.to.class": INFO

  appenders:
    - type: file
      currentLogFilename: .logs/mylogs.log
      archivedLogFilenamePattern: .logs/archive.%d.log.gz
      archivedFileCount: 14

In addition, a recorder is created in my application:

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;    

private final Logger OpLogger = LoggerFactory.getLogger("mylogger");
(and)
private final Logger ClassLogger = LoggerFactory.getLogger(pathToClass.class);

Make some test records in main():

OpLogger.info("test 1");
ClassLogger.info("test 2);

There is no problem when the application starts and runs; But I didn't get any logs (except jetty's access log, of course, correctly printed to mylogs. Log), whether in stdout or mylogs. Log Log file Instead, if I delete configuration According to the recorder configuration in YML, I will print all logs to stdout Maybe this is a dropwizard problem, or I have to report to configuration YML add something? I am using dropwizard 0.8 0

Solution

Update the latest version of dropwizard to support log configuration out of the box

I encountered the same problem and tried to set the dropwizard (0.8.4) with a separate file I have the same problem So I dug deeper and found a solution for me (not the cleanest, but I can't seem to work in a different way)

The problem is that loggingfactory #configure automatically adds each appender to root This is not ideal, so it needs to be covered What I do is:

>Overwrite loggingfactory

This is a bit messy because there are some things that need to be sadly copied: (this is my implementation:

import java.io.PrintStream;
import java.lang.management.ManagementFactory;
import java.util.Map;

import javax.management.InstanceAlreadyExistsException;
import javax.management.MBeanRegistrationException;
import javax.management.MBeanServer;
import javax.management.MalformedObjectNameException;
import javax.management.NotCompliantMBeanException;
import javax.management.ObjectName;

import org.slf4j.LoggerFactory;
import org.slf4j.bridge.SLF4JBridgeHandler;

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.collect.ImmutableMap;

import ch.qos.logback.classic.Level;
import ch.qos.logback.classic.Logger;
import ch.qos.logback.classic.LoggerContext;
import ch.qos.logback.classic.PatternLayout;
import ch.qos.logback.classic.jmx.JMXConfigurator;
import ch.qos.logback.classic.jul.LevelChangePropagator;
import ch.qos.logback.classic.spi.ILoggingEvent;
import ch.qos.logback.core.Appender;
import ch.qos.logback.core.util.StatusPrinter;
import io.dropwizard.logging.AppenderFactory;
import io.dropwizard.logging.LoggingFactory;

public class BetterDropWizardLoggingConfig extends LoggingFactory {

    @JsonIgnore
    final LoggerContext loggerContext;

    @JsonIgnore
    final PrintStream configurationErroRSStream;

    @JsonProperty("loggerMapping")
    private ImmutableMap<String,String> loggerMappings;

    private static void hijackJDKLogging() {
        SLF4JBridgeHandler.removeHandlersForRootLogger();
        SLF4JBridgeHandler.install();
    }

    public BetterDropWizardLoggingConfig() {
        PatternLayout.defaultConverterMap.put("h",HostNameConverter.class.getName());
        this.loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();
        this.configurationErroRSStream = System.err;
    }

    private Logger configureLevels() {
        final Logger root = loggerContext.getLogger(org.slf4j.Logger.ROOT_LOGGER_NAME);
        loggerContext.reset();

        final LevelChangePropagator propagator = new LevelChangePropagator();
        propagator.setContext(loggerContext);
        propagator.setResetJUL(true);

        loggerContext.addListener(propagator);

        root.setLevel(getLevel());

        for (Map.Entry<String,Level> entry : getLoggers().entrySet()) {
            loggerContext.getLogger(entry.getKey()).setLevel(entry.getValue());
        }

        return root;
    }

    @Override
    public void configure(MetricRegistry metricRegistry,String name) {
        hijackJDKLogging();

        final Logger root = configureLevels();

        for (AppenderFactory output : getAppenders()) {
            Appender<ILoggingEvent> build = output.build(loggerContext,name,null);
            if(output instanceof MappedLogger && ((MappedLogger) output).getLoggerName() != null) {
                String appenderName = ((MappedLogger) output).getLoggerName();
                String loggerName = loggerMappings.get(appenderName);
                Logger logger = this.loggerContext.getLogger(loggerName);
                logger.addAppender(build);
            } else {
                root.addAppender(build);
            }
        }

        StatusPrinter.setPrintStream(configurationErroRSStream);
        try {
            StatusPrinter.printIfErrorsOccured(loggerContext);
        } finally {
            StatusPrinter.setPrintStream(System.out);
        }

        final MBeanServer server = ManagementFactory.getPlatformMBeanServer();
        try {
            final ObjectName objectName = new ObjectName("io.dropwizard:type=Logging");
            if (!server.isRegistered(objectName)) {
                server.registerMBean(new JMXConfigurator(loggerContext,server,objectName),objectName);
            }
        } catch (MalformedObjectNameException | InstanceAlreadyExistsException | NotCompliantMBeanException
                | MBeanRegistrationException e) {
            throw new RuntimeException(e);
        }

        configureInstrumentation(root,metricRegistry);
    }

    private void configureInstrumentation(Logger root,MetricRegistry metricRegistry) {
        final InstrumentedAppender appender = new InstrumentedAppender(metricRegistry);
        appender.setContext(loggerContext);
        appender.start();
        root.addAppender(appender);
    }

}

You can do this, I have to copy / paste some private members and methods to make things work as expected

I added a new field:

@JsonProperty("loggerMapping")
private ImmutableMap<String,String> loggerMappings;

This allows me to configure mappings for each logger This is not out of the box, because I can't get a name (the default appender name of the dropwizard is very inconvenient...)

So I added a new logger and replaced the host name in my example, which I need for different reasons To do this, I override the old fileappenderfactory and implement my own mappedlogger interface Implement here:

import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonTypeName;

import ch.qos.logback.classic.LoggerContext;
import ch.qos.logback.classic.spi.ILoggingEvent;
import ch.qos.logback.core.FileAppender;
import ch.qos.logback.core.rolling.RollingFileAppender;
import io.dropwizard.logging.AppenderFactory;
import io.dropwizard.logging.FileAppenderFactory;

@JsonTypeName("hostnameFile")
public class HostnameFileAppender extends FileAppenderFactory implements AppenderFactory,MappedLogger {

    private static String uuid = UUID.randomUUID().toString();

    @JsonProperty
    private String name;

    public void setCurrentLogFilename(String currentLogFilename) {
        super.setCurrentLogFilename(substitute(currentLogFilename));
    }

    private String substitute(final String pattern) {
        String substitute = null;

        try {
            substitute = InetAddress.getLocalHost().getHostName();
        } catch (UnkNownHostException e) {
            System.err.println("Failed to get local hostname:");
            e.printStackTrace(System.err);
            substitute = uuid;
            System.err.println("Using " + substitute + " as fallback.");
        }
        return pattern.replace("${HOSTNAME}",substitute);
    }

    @Override
    public void setArchivedLogFilenamePattern(String archivedLogFilenamePattern) {
        super.setArchivedLogFilenamePattern(substitute(archivedLogFilenamePattern));
    }

    @Override
    public String getLoggerName() {
        return name;
    }
}

Note that in order to add a new JSON type, you must follow the Javadoc in appenderfactory (add meta inf to the classpath and make the new appender discoverable)

So far, we now have a configuration that can receive recorder mappings, and we have a recorder with a selectable name

In the configuration method, I now combine the two:

for (AppenderFactory output : getAppenders()) {
        Appender<ILoggingEvent> build = output.build(loggerContext,null);
        if(output instanceof MappedLogger && ((MappedLogger) output).getLoggerName() != null) {
            String appenderName = ((MappedLogger) output).getLoggerName();
            String loggerName = loggerMappings.get(appenderName);
            Logger logger = this.loggerContext.getLogger(loggerName);
            logger.addAppender(build);
        } else {
            root.addAppender(build);
        }
    }

For backward compatibility, I keep the default behavior If no name is defined, the appender is added to the root logger Otherwise, I parse the input logger and add an appender as needed

Last but not least, the old yaml configuration:

logging:
  # The default level of all loggers. Can be OFF,ERROR,WARN,INFO,DEBUG,TRACE,or ALL.
  level: INFO

  loggers:
    "EVENT" : INFO

  loggerMapping:
    # for easier search this is defined as: appenderName -> loggerName rather than the other way around
    "eventLog" : "EVENT"

  appenders:
   - type: console   
     threshold: ALL
     logFormat: "myformat"

   - type: hostnameFile # NOTE THE NEW TYPE WITH HOSTNAME RESOLVE
     currentLogFilename: /Users/artur/tmp/log/my-${HOSTNAME}.log
     threshold: ALL
     archive: true
     archivedLogFilenamePattern: mypattern
     archivedFileCount: 31
     timeZone: UTC
     logFormat: "myFormat"

   - type: hostnameFile
     name: eventLog # NOTE THE APPENDER NAME
     currentLogFilename: something
     threshold: ALL
     archive: true
     archivedLogFilenamePattern: something
     archivedFileCount: 31
     timeZone: UTC
     logFormat: "myFormat"

   - type: hostnameFile
     currentLogFilename: something
     threshold: ERROR
     archive: true
     archivedLogFilenamePattern: something
     archivedFileCount: 31
     timeZone: UTC
     logFormat: "myFormat"

As you can see, I map the event appender to the event logger In this way, all my events will end in file a, and other information will end elsewhere

I hope it helps It may not be the cleanest solution, but I don't think dropwizard allows this feature at present