Refactor argument parsing and improve LokiClient send.

README.md

@@ -1,33 +1,35 @@
 # Syslog Server
 
-All received messages are written to *stdout* and/or forwarded to another syslog server.
+All received messages are written to *stdout* and/or forwarded to a remote logging solution.
 
 The syslog server is able to listen on both UDP and TCP and parses syslog messages in either RFC5424 or RFC3164 (BSD) format.
 
 The default syslog port (514) requires you to run syslogd as root / administrator.
 If you do not wish to do so, you can choose a port number (with the *-p* or *--port* flag) above 1024.
 
+Supported remote logging solutions are Syslog (RFC5424 over UDP), Graylog (GELF over UDP) and Grafana Loki.
+
 ## Usage Instructions
 
 - Install the syslogd package (*.deb* or *.rpm*) from [downloads](https://bitbucket.org/mnellemann/syslogd/downloads/) or build from source.
 - Run *bin/syslogd*, use the *-h* option for help :)
 
-````
+```text
-Usage: syslogd [-dghV] [--[no-]ansi] [--[no-]stdout] [--[no-]tcp] [--[no-]udp]
+Usage: syslogd [-dhV] [--[no-]ansi] [--[no-]stdout] [--[no-]tcp] [--[no-]udp]
-               [--rfc5424] [-f=<host>] [-p=<port>]
+               [--rfc5424] [-g=<uri>] [-l=<url>] [-p=<num>] [-s=<uri>]
-Syslog Server
   -d, --debug          Enable debugging [default: 'false'].
-  -f, --forward=<host>   Forward to UDP host[:port] (RFC-5424).
+  -g, --gelf=<uri>     Forward to Graylog <udp://host:port>.
-  -g, --gelf             Forward in Graylog (GELF) JSON format.
   -h, --help           Show this help message and exit.
+  -l, --loki=<url>     Forward to Grafana Loki <http://host:port>.
       --[no-]ansi      Output ANSI colors [default: true].
       --[no-]stdout    Output messages to stdout [default: true].
       --[no-]tcp       Listen on TCP [default: true].
       --[no-]udp       Listen on UDP [default: true].
-  -p, --port=<port>      Listening port [default: 514].
+  -p, --port=<num>     Listening port [default: 514].
       --rfc5424        Parse RFC-5424 messages [default: RFC-3164].
+  -s, --syslog=<uri>   Forward to Syslog <udp://host:port> (RFC-5424).
   -V, --version        Print version information and exit.
-````
+```
 
 ### Examples
 
@@ -46,30 +48,40 @@ or, if installed as a *deb* or *rpm* package:
 Listening on the standard syslog port (requires root privileges) and forwarding messages on to another log-system on a non-standard port.
 
 ```
-java -jar /path/to/syslogd-x.y.z-all.jar --forward remotehost:1514
+java -jar /path/to/syslogd-x.y.z-all.jar --syslog udp://remotehost:514
 ```
 
 Forwarding to a Graylog server in GELF format.
 
 ```
-java -jar /path/to/syslogd-x.y.z-all.jar --forward remotehost:12201 --gelf
+java -jar /path/to/syslogd-x.y.z-all.jar --gelf udp://remotehost:12201
 ```
 
+Forwarding to a Grafana Loki server.
+
+```
+java -jar /path/to/syslogd-x.y.z-all.jar --loki http://remotehost:3100
+```
 
 If you don't want any output locally (only forwarding), you can use the ```--no-stdout``` flag.
 
 
 ## Notes
 
+### IBM AIX and VIO Servers
+
 Syslog messages from AIX (and IBM Power Virtual I/O Servers) can be troublesome with some logging solutions. These can be received with
-syslogd and optionally forwarded on to Graylog, Splunk or other logging solutions.
+syslogd and then forwarded on to your preferred logging solution.
 
 
-## Development
+## Development Notes
-
 
 ### Test Grafana Loki
 
+Run Loki and Grafana in local containers to test.
+
 ```shell
 docker run --rm -d --name=loki -p 3100:3100 grafana/loki
+docker run --rm -d --name=grafana --link loki:loki -p 3000:3000 grafana/grafana:7.1.3
 ```
+

gradle.properties

@@ -1,3 +1,3 @@
 id            = syslogd
 group         = biz.nellemann.syslogd
-version       = 1.0.13
+version       = 1.0.14

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

@@ -30,6 +30,9 @@ import picocli.CommandLine.Command;
 
 import java.io.IOException;
 import java.net.InetSocketAddress;
+import java.net.URI;
+import java.net.URL;
+import java.util.Locale;
 import java.util.concurrent.Callable;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -46,7 +49,7 @@ public class Application implements Callable<Integer>, LogListener {
     private LokiClient lokiClient;
 
 
-    @CommandLine.Option(names = {"-p", "--port"}, description = "Listening port [default: 514].", defaultValue = "514")
+    @CommandLine.Option(names = {"-p", "--port"}, description = "Listening port [default: 514].", defaultValue = "514", paramLabel = "<num>")
     private int port;
 
     @CommandLine.Option(names = "--no-udp", negatable = true, description = "Listen on UDP [default: true].", defaultValue = "true")
@@ -64,14 +67,14 @@ public class Application implements Callable<Integer>, LogListener {
     @CommandLine.Option(names = "--rfc5424", description = "Parse RFC-5424 messages [default: RFC-3164].", defaultValue = "false")
     private boolean rfc5424;
 
-    @CommandLine.Option(names = { "-s", "--syslog"}, description = "Forward to Syslog UDP host[:port] (RFC-5424).", paramLabel = "<host>")
+    @CommandLine.Option(names = { "-s", "--syslog"}, description = "Forward to Syslog <udp://host:port> (RFC-5424).", paramLabel = "<uri>")
-    private String syslog;
+    private URI syslog;
 
-    @CommandLine.Option(names = { "-g", "--gelf"}, description = "Forward to Graylog host[:port] (GELF).", paramLabel = "<host>")
+    @CommandLine.Option(names = { "-g", "--gelf"}, description = "Forward to Graylog <udp://host:port>.", paramLabel = "<uri>")
-    private String gelf;
+    private URI gelf;
 
-    @CommandLine.Option(names = { "-l", "--loki"}, description = "Forward to Grafana Loki.", paramLabel = "<url>")
+    @CommandLine.Option(names = { "-l", "--loki"}, description = "Forward to Grafana Loki <http://host:port>.", paramLabel = "<url>")
-    private String loki;
+    private URL loki;
 
     @CommandLine.Option(names = { "-d", "--debug" }, description = "Enable debugging [default: 'false'].")
     private boolean enableDebug = false;
@@ -90,17 +93,26 @@ public class Application implements Callable<Integer>, LogListener {
             syslogParser = new SyslogParserRfc3164();
         }
 
-        if(syslog != null && !syslog.isEmpty()) {
+        if(syslog != null) {
+            if(syslog.getScheme().toLowerCase(Locale.ROOT).equals("udp")) {
                 udpClient = new UdpClient(getInetSocketAddress(syslog));
                 doForward = true;
+            } else {
+                throw new UnsupportedOperationException("Syslog protocol not implemented: " + syslog.getScheme());
+            }
         }
 
-        if(gelf != null && !gelf.isEmpty()) {
+        if(gelf != null) {
+            System.err.println(gelf.getScheme());
+            if(gelf.getScheme().toLowerCase(Locale.ROOT).equals("udp")) {
                 gelfClient = new UdpClient(getInetSocketAddress(gelf));
                 doForward = true;
+            } else {
+                throw new UnsupportedOperationException("GELF protocol not implemented: " + gelf.getScheme());
+            }
         }
 
-        if(loki != null && !loki.isEmpty()) {
+        if(loki != null) {
             lokiClient = new LokiClient(loki);
             doForward = true;
         }
@@ -167,6 +179,12 @@ public class Application implements Callable<Integer>, LogListener {
     }
 
 
+    private InetSocketAddress getInetSocketAddress(URI input) {
+        InetSocketAddress inetSocketAddress = new InetSocketAddress(input.getHost(), input.getPort());
+        return inetSocketAddress;
+    }
+
+
     private InetSocketAddress getInetSocketAddress(String input) {
 
         String dstHost;

src/main/java/biz/nellemann/syslogd/net/LokiClient.java

@@ -3,9 +3,7 @@ package biz.nellemann.syslogd.net;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.io.BufferedReader;
 import java.io.IOException;
-import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.net.*;
 import java.nio.charset.StandardCharsets;
@@ -17,48 +15,32 @@ public class LokiClient {
     private final URL url;
 
 
-    public LokiClient(String url) throws MalformedURLException {
+    public LokiClient(URL url) {
-        this.url = new URL(url);
+        this.url = url;
     }
 
 
     public void send(String msg) throws MalformedURLException {
 
         URL pushUrl = new URL(url, "/loki/api/v1/push");
-        log.warn("send() - URL: " + pushUrl.toString());
-
         HttpURLConnection con = null;
         try {
             con = (HttpURLConnection)pushUrl.openConnection();
             con.setRequestMethod("POST");
             con.setRequestProperty("Content-Type", "application/json");
-            //con.setRequestProperty("Content-Type", "application/json; utf-8");
-            //con.setRequestProperty("Accept", "application/json");
             con.setDoOutput(true);
 
-            byte[] input = msg.getBytes(StandardCharsets.US_ASCII);
+            byte[] input = msg.getBytes(StandardCharsets.UTF_8);
             try(OutputStream os = con.getOutputStream()) {
                 os.write(input, 0, input.length);
-                log.warn("send() - Data: " + msg);
             } catch (IOException e) {
-                e.printStackTrace();
+                log.warn(e.getMessage());
             }
 
-            StringBuilder content;
+            int responseCode = con.getResponseCode();
-
+            if(responseCode != 204) {
-            try (BufferedReader br = new BufferedReader(
+                log.warn("send() - response: " + responseCode);
-                new InputStreamReader(con.getInputStream()))) {
-
-                String line;
-                content = new StringBuilder();
-
-                while ((line = br.readLine()) != null) {
-                    content.append(line);
-                    content.append(System.lineSeparator());
             }
-            }
-
-            System.out.println(content.toString());
 
         } catch (IOException e) {
             log.warn("send() - " + e.getMessage());