Add log file and skeleton code for visualization data

.gitignore

@@ -7,3 +7,4 @@
 /.meghanada/
 *.csv
 /config/config.properties
+/logs/viz.log

build.gradle

@@ -41,6 +41,13 @@ run {
     }
 }
 
+task runViz(type: JavaExec) {
+    dependsOn classes
+    systemProperty 'logback.configurationFile', 'src/main/resources/logback.xml'
+    classpath sourceSets.main.runtimeClasspath
+    main = 'Viz'
+}
+
 testlogger {
     theme 'standard'
 	showStandardStreams true

src/main/java/EsperProcessor.java

@@ -21,7 +21,8 @@ import ats.plugin.OHLCPlugInViewFactory;
 
 
 public class EsperProcessor implements TickProcessor {
-    final Logger log = LoggerFactory.getLogger(EsperProcessor.class);
+    static final Logger log = LoggerFactory.getLogger(EsperProcessor.class);
+    static final Logger viz = LoggerFactory.getLogger(Viz.LOG_NAME);
     EPServiceProvider engine;
     TradingManager trader;
 
@@ -49,6 +50,7 @@ public class EsperProcessor implements TickProcessor {
 
         // addLogStatement("TickEvent");
 
+        addVizDataStreamHandler();
         addLogStreamHandler();
 
         // respond to long entry events
@@ -161,6 +163,17 @@ public class EsperProcessor implements TickProcessor {
         return statement;
     }
 
+    /**
+     * Add a simple EPL statement to the Esper engine that logs any
+     * event that matches the event name.
+     */
+    private EPStatement addVizDataStreamHandler() {
+        return addStatement("select * from VizDataStream",
+                            (newData, oldData) -> {
+                                viz.info(newData[0].get("event").toString());
+                            });
+    }
+
     /**
      * Add a simple EPL statement to the Esper engine that logs any
      * event that matches the event name.

src/main/java/Viz.java

@@ -0,0 +1,34 @@
+import java.util.StringJoiner;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Viz converts visualization log data into a graphical
+ * representation.
+ */
+public class Viz {
+	public static final String LOG_NAME = "viz-data";
+    static final Logger log = LoggerFactory.getLogger("Viz");
+    static final Logger viz = LoggerFactory.getLogger(LOG_NAME);
+
+
+    /**
+     * Run the converter.
+     */
+    public static void main(String[] args) {
+
+    }
+
+    /**
+     * Convert event data to our preferred format.  This format can be
+     * placed into a log, which we can later read back in.
+     */
+    public static String eventString(Object... objects) {
+        StringJoiner sj = new StringJoiner(", ");
+        for (Object o : objects) {
+            sj.add(o != null ? o.toString() : "null");
+        }
+        return sj.toString();
+    }
+}

src/main/resources/logback.xml

@@ -16,6 +16,7 @@
     </encoder>
   </appender>
 
+  <!-- The primary log file.  For all runtime messages. -->
   <appender name="FILE" class="ch.qos.logback.core.FileAppender">
     <file>logs/run.log</file>
     <append>false</append>
@@ -24,6 +25,20 @@
     </encoder>
   </appender>
 
+  <!-- Log file for visualization data.  Read by the Viz app. -->
+  <appender name="VIZ-FILE" class="ch.qos.logback.core.FileAppender">
+    <file>logs/viz.log</file>
+    <append>false</append>
+    <encoder>
+      <pattern>%msg%n</pattern>
+    </encoder>
+  </appender>
+
+  <!-- additivity=false ensures viz data only goes to the viz log -->
+  <logger name="viz-data" level="DEBUG" additivity="false">
+    <appender-ref ref="VIZ-FILE"/>
+  </logger>
+
   <root level="DEBUG">
       <appender-ref ref="STDOUT" />
       <appender-ref ref="FILE" />