add a feature to generate the datasource xml for rrdtool.

Author: lookfirst

heapmemory.json

@@ -11,7 +11,8 @@
             "templateFile" : "heapmemory-rrd-template.xml",
             "outputFile" : "target/heap.rrd",
             "binaryPath" : "/opt/local/bin",
-            "debug" : true
+            "debug" : true,
+            "generate" : true
         }
       } ]
     } ]

src/com/googlecode/jmxtrans/model/output/RRDToolWriter.java

@@ -44,7 +44,8 @@ public class RRDToolWriter extends BaseOutputWriter {
     private File binaryPath = null;
     private static final char[] PERIOD = {'.'};
     private static final char[] INITIALS = {' ', '.'};
-    
+    private static final String GENERATE = "generate";
+
     /** */
     public RRDToolWriter() {
     }
@@ -106,6 +107,20 @@ public void doWrite(Query query) throws Exception {
             }
         }
 
+        if (isDebugEnabled() && this.getBooleanSetting(GENERATE)) {
+            StringBuilder sb = new StringBuilder("\n");
+            for (Result res : results) {
+                Map<String, Object> values = res.getValues();
+                if (values != null) {
+                    for (Entry<String, Object> entry : values.entrySet()) {
+                        String key = getDataSourceName(res.getAttributeName(), entry.getKey());
+                        sb.append("<datasource><name>" + key + "</name><type>GAUGE</type><heartbeat>400</heartbeat><min>U</min><max>U</max></datasource>\n");
+                    }
+                }
+            }
+            log.debug(sb.toString());
+        }
+        
         if (dataMap.keySet().size() > 0 && dataMap.values().size() > 0) {
             rrdToolUpdate(StringUtils.join(dataMap.keySet(), ':'), StringUtils.join(dataMap.values(), ':'));
         } else {

src/com/googlecode/jmxtrans/util/BaseOutputWriter.java

@@ -40,6 +40,10 @@ public void setSettings(Map<String, Object> settings) {
         this.settings = settings;
     }
 
+    public boolean getBooleanSetting(String key) {
+        return this.getSettings().containsKey(key) ? (Boolean) this.getSettings().get(key) : Boolean.FALSE;
+    }
+
     @JsonIgnore
     public boolean isDebugEnabled() {
         if (debugEnabled == null) {