Improve UDP reception and add file output and ansi flag on/off.

build.gradle

@@ -59,7 +59,7 @@ ospackage {
 
 buildRpm {
     dependsOn startShadowScripts
-    requires('java-1.8.0-openjdk-headless')
+    //requires('java-1.8.0-openjdk-headless')
     os = LINUX
 }
 

gradle.properties

@@ -1,3 +1,3 @@
 id            = syslogd
 group         = biz.nellemann.syslogd
-version       = 1.0.0
+version       = 1.0.1

src/main/java/biz/nellemann/syslogd/LogEvent.java

@@ -20,9 +20,9 @@ import java.util.EventObject;
 
 public class LogEvent extends EventObject {
 
-    private String message;
+    private final String message;
 
-    public LogEvent(Object source, String message ) {
+    public LogEvent(final Object source, final String message ) {
         super( source );
         this.message = message;
     }

src/main/java/biz/nellemann/syslogd/LogListener.java

@@ -15,6 +15,8 @@
  */
 package biz.nellemann.syslogd;
 
+import java.io.IOException;
+
 public interface LogListener {
     void onLogEvent(LogEvent event);
 }

src/main/java/biz/nellemann/syslogd/SyslogMessage.java

@@ -44,12 +44,26 @@ public class SyslogMessage {
     String structuredData;
 
     // The MSG part contains a free-form message that provides information about the event.
-    String message;
+    final private String message;
+
+    SyslogMessage(final String message) {
+        this.message = message;
+    }
+
 
 
     public String toString() {
-        //return String.format("%s %s %s: %s", timestamp.toString(), hostname, application, message);
+        StringBuilder sb = new StringBuilder();
+        sb.append(timestamp.toString() + " ");
+        sb.append("[" + facility + "." + severity + "]");
+        sb.append("\t" + hostname);
+        sb.append("\t" + application);
+        sb.append("\t" + message);
+        return sb.toString();
+    }
 
+
+    public String toAnsiString() {
         StringBuilder sb = new StringBuilder();
 
         sb.append(timestamp.toString() + " ");
@@ -65,7 +79,7 @@ public class SyslogMessage {
 
         sb.append(Ansi.BLUE); sb.append("\t" + hostname); sb.append(Ansi.RESET);
         sb.append(Ansi.CYAN); sb.append("\t" + application); sb.append(Ansi.RESET);
-        sb.append("\t" + message); sb.append(Ansi.CLEAR_LINE);
+        sb.append("\t" + message);
 
         return sb.toString();
     }

src/main/java/biz/nellemann/syslogd/SyslogParser.java

@@ -35,7 +35,7 @@ public class SyslogParser {
     private final static Logger log = LoggerFactory.getLogger(SyslogParser.class);
 
 
-    public static SyslogMessage parseRfc3164(String input) throws NumberFormatException {
+    public static SyslogMessage parseRfc3164(final String input) throws NumberFormatException {
 
         Pattern pattern = Pattern.compile("^<(\\d{1,3})>(\\D{3} \\d{2} \\d{2}:\\d{2}:\\d{2})\\s+(?:Message forwarded from )?([^\\s:]+):?\\s+(\\S+): (.*)", Pattern.CASE_INSENSITIVE);
         Matcher matcher = pattern.matcher(input);
@@ -45,11 +45,11 @@ public class SyslogParser {
             return null;
         }
 
-        String pri = matcher.group(1);
+        final String pri = matcher.group(1);
-        String date = matcher.group(2);
+        final String date = matcher.group(2);
-        String hostname = matcher.group(3);
+        final String hostname = matcher.group(3);
-        String application = matcher.group(4);
+        final String application = matcher.group(4);
-        String message = matcher.group(5);
+        final String message = matcher.group(5);
 
         log.debug("PRI: " + pri);
         log.debug("DATE: " + date);
@@ -62,19 +62,18 @@ public class SyslogParser {
         log.debug("facility: " + facility);
         log.debug("severity: " + severity);
 
-        SyslogMessage syslogMessage = new SyslogMessage();
+        SyslogMessage syslogMessage = new SyslogMessage(message);
         syslogMessage.facility = Facility.getByNumber(facility);
         syslogMessage.severity = Severity.getByNumber(severity);
         syslogMessage.timestamp = parseRfc3164Timestamp(date);
         syslogMessage.hostname = hostname;
         syslogMessage.application = application;
-        syslogMessage.message = message;
 
         return syslogMessage;
     }
 
 
-    public static SyslogMessage parseRfc5424(String input) throws NumberFormatException {
+    public static SyslogMessage parseRfc5424(final String input) throws NumberFormatException {
 
         Pattern pattern = Pattern.compile("^<(\\d{1,3})>(\\d+)\\s+(\\S+)\\s+(\\S+)\\s+(\\S+)\\s+(\\S+)\\s+(\\S+)\\s+(\\[.*\\])\\s+(\\S+)", Pattern.CASE_INSENSITIVE);
         Matcher matcher = pattern.matcher(input);
@@ -84,15 +83,15 @@ public class SyslogParser {
             return null;
         }
 
-        String pri = matcher.group(1);
+        final String pri = matcher.group(1);
-        String ver = matcher.group(2);
+        final String ver = matcher.group(2);
-        String date = matcher.group(3);
+        final String date = matcher.group(3);
-        String host = matcher.group(4);
+        final String host = matcher.group(4);
-        String app = matcher.group(5);
+        final String app = matcher.group(5);
-        String procId = matcher.group(6);
+        final String procId = matcher.group(6);
-        String msgId = matcher.group(7);
+        final String msgId = matcher.group(7);
-        String data = matcher.group(8);
+        final String data = matcher.group(8);
-        String msg = matcher.group(9);
+        final String msg = matcher.group(9);
 
         log.debug("PRI: " + pri);
         log.debug("VER: " + ver);
@@ -109,7 +108,7 @@ public class SyslogParser {
         log.debug("facility: " + facility);
         log.debug("severity: " + severity);
 
-        SyslogMessage syslogMessage = new SyslogMessage();
+        SyslogMessage syslogMessage = new SyslogMessage(msg);
         syslogMessage.facility = Facility.getByNumber(facility);
         syslogMessage.severity = Severity.getByNumber(severity);
         syslogMessage.version = Integer.parseInt(ver);
@@ -122,7 +121,6 @@ public class SyslogParser {
         if(msgId != null && !msgId.equals("-"))
             syslogMessage.messageId = msgId;
         syslogMessage.structuredData = data;
-        syslogMessage.message = msg;
 
         return syslogMessage;
     }

src/main/java/biz/nellemann/syslogd/SyslogServer.java

@@ -19,26 +19,37 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import picocli.CommandLine;
 import picocli.CommandLine.Command;
+
+import java.io.*;
 import java.util.concurrent.Callable;
 
-@Command(name = "syslogd", mixinStandardHelpOptions = true, version = "syslogd 1.0",
+@Command(name = "syslogd",
-        description = "Simple syslog server that prints messages to stdout.")
+        mixinStandardHelpOptions = true,
+        description = "Basic syslog server.",
+        versionProvider = biz.nellemann.syslogd.VersionProvider.class)
 public class SyslogServer implements Callable<Integer>, LogListener {
 
     private final static Logger log = LoggerFactory.getLogger(SyslogServer.class);
+    private BufferedWriter bw;
 
-    @CommandLine.Option(names = {"-p", "--port"}, description = "Listening port, 514 (privileged) by default.")
+    @CommandLine.Option(names = {"-p", "--port"}, description = "Listening port [default: 514]")
     private int port = 514;
 
-    @CommandLine.Option(names = "--no-udp", negatable = true, description = "Listen on UDP, true by default.")
+    @CommandLine.Option(names = "--no-udp", negatable = true, description = "Listen on UDP [default: true]")
     boolean udpServer = true;
 
-    @CommandLine.Option(names = "--no-tcp", negatable = true, description = "Listen on TCP, true by default.")
+    @CommandLine.Option(names = "--no-tcp", negatable = true, description = "Listen on TCP [default: true]")
     boolean tcpServer = true;
 
-    @CommandLine.Option(names = "--rfc3164", negatable = false, description = "Parse RFC3164 syslog message, RFC5424 by default.")
+    @CommandLine.Option(names = "--rfc3164", negatable = false, description = "Parse RFC3164 messages [default: RFC5424]")
     boolean rfc3164 = false;
 
+    @CommandLine.Option(names = "--no-ansi", negatable = true, description = "ANSI in output [default: true]")
+    boolean ansiOutput = true;
+
+    @CommandLine.Option(names = {"-f", "--file"}, description = "Write output to file [default: STDOUT]")
+    File outputFile;
+
     public static void main(String... args) {
         int exitCode = new CommandLine(new SyslogServer()).execute(args);
         System.exit(exitCode);
@@ -48,6 +59,15 @@ public class SyslogServer implements Callable<Integer>, LogListener {
     @Override
     public Integer call() throws Exception {
 
+        FileOutputStream fos = null;
+        OutputStreamWriter w;
+
+        if(outputFile != null) {
+            fos = new FileOutputStream(outputFile);
+            w = new OutputStreamWriter(fos, "UTF-8");
+            bw = new BufferedWriter(w);
+        }
+
         if(udpServer) {
             UdpServer udpServer = new UdpServer(port);
             udpServer.addEventListener(this);
@@ -60,6 +80,11 @@ public class SyslogServer implements Callable<Integer>, LogListener {
             tcpServer.start();
         }
 
+        if(outputFile != null) {
+            bw.close();
+            fos.close();
+        }
+
         return 0;
     }
 
@@ -67,6 +92,7 @@ public class SyslogServer implements Callable<Integer>, LogListener {
     @Override
     public void onLogEvent(LogEvent event) {
 
+        // Parse message
         String message = event.getMessage();
         SyslogMessage msg = null;
         try {
@@ -80,9 +106,37 @@ public class SyslogServer implements Callable<Integer>, LogListener {
         }
 
         if(msg != null) {
-            System.out.println(msg);
+            if(bw != null) {
+                writeToFile(msg);
+            } else {
+                writeToStdout(msg);
+            }
         }
 
     }
 
+
+    void writeToFile(SyslogMessage msg) {
+        try {
+            if(ansiOutput) {
+                bw.append(msg.toAnsiString());
+            } else {
+                bw.append(msg.toString());
+            }
+            bw.newLine();
+            bw.flush();
+        } catch (IOException e) {
+            log.error("file error", e);
+        }
+    }
+
+
+    void writeToStdout(SyslogMessage msg) {
+        if(ansiOutput) {
+            System.out.println(msg.toAnsiString());
+        } else {
+            System.out.println(msg);
+        }
+    }
+
 }

src/main/java/biz/nellemann/syslogd/UdpServer.java

@@ -38,13 +38,13 @@ public class UdpServer extends Thread {
 
     public void run() {
 
-        byte[] buf = new byte[10000];
+        byte[] buf = new byte[4096];
         DatagramPacket packet = new DatagramPacket(buf, buf.length);
 
         while (listen) {
             try {
                 socket.receive(packet);
-                String packetData = new String(packet.getData(), "UTF8");
+                String packetData = new String(packet.getData(), packet.getOffset(), packet.getLength(), "UTF8");
                 sendEvent(packetData);
             } catch (Exception e) {
                 e.printStackTrace();

src/main/java/biz/nellemann/syslogd/VersionProvider.java

@@ -0,0 +1,22 @@
+package biz.nellemann.syslogd;
+
+import picocli.CommandLine;
+
+import java.io.IOException;
+import java.net.URL;
+import java.util.Properties;
+
+class VersionProvider implements CommandLine.IVersionProvider {
+
+    public String[] getVersion() throws IOException {
+
+        URL url = getClass().getResource("/version.properties");
+        if (url == null) {
+            return new String[] { "No version.txt file found in the classpath." };
+        }
+        Properties properties = new Properties();
+        properties.load(url.openStream());
+        return new String[] { "${COMMAND-FULL-NAME} " + properties.getProperty("VERSION_GRADLE") + "-" + properties.getProperty("VERSION_BUILD") };
+    }
+
+}