add version information to status

client/src/main/java/com/metamx/druid/http/StatusResource.java

@@ -1,9 +1,29 @@
+/*
+ * Druid - a distributed column store.
+ * Copyright (C) 2013  Metamarkets Group Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
 package com.metamx.druid.http;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+
 import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.Produces;
-import javax.ws.rs.core.Response;
 
 /**
  */
@@ -11,21 +31,73 @@ import javax.ws.rs.core.Response;
 public class StatusResource
 {
   @GET
-  @Produces("text/plain")
-  public Response doGet()
+  @Produces("application/json")
+  public Status doGet()
   {
-    StringBuffer buf = new StringBuffer();
+    return new Status(
+        StatusResource.class.getPackage().getImplementationVersion(),
+        new Memory(Runtime.getRuntime())
+    );
+  }
 
-    Runtime runtime = Runtime.getRuntime();
-    long maxMemory = runtime.maxMemory();
-    long totalMemory = runtime.totalMemory();
-    long freeMemory = runtime.freeMemory();
+  public static class Status {
+    final String version;
+    final Memory memory;
 
-    buf.append(String.format("Max Memory:\t%,18d\t%1$d%n", maxMemory));
-    buf.append(String.format("Total Memory:\t%,18d\t%1$d%n", totalMemory));
-    buf.append(String.format("Free Memory:\t%,18d\t%1$d%n", freeMemory));
-    buf.append(String.format("Used Memory:\t%,18d\t%1$d%n", totalMemory - freeMemory));
+    public Status(String version, Memory memory)
+    {
+      this.version = version;
+      this.memory = memory;
+    }
 
-    return Response.ok(buf.toString()).build();
+    @JsonProperty
+    public String getVersion()
+    {
+      return version;
+    }
+
+    @JsonProperty
+    public Memory getMemory()
+    {
+      return memory;
+    }
+  }
+
+  public static class Memory {
+    final long maxMemory;
+    final long totalMemory;
+    final long freeMemory;
+    final long usedMemory;
+
+    public Memory(Runtime runtime) {
+      maxMemory = runtime.maxMemory();
+      totalMemory = runtime.totalMemory();
+      freeMemory = runtime.freeMemory();
+      usedMemory = totalMemory - freeMemory;
+    }
+
+    @JsonProperty
+    public long getMaxMemory()
+    {
+      return maxMemory;
+    }
+
+    @JsonProperty
+    public long getTotalMemory()
+    {
+      return totalMemory;
+    }
+
+    @JsonProperty
+    public long getFreeMemory()
+    {
+      return freeMemory;
+    }
+
+    @JsonProperty
+    public long getUsedMemory()
+    {
+      return usedMemory;
+    }
   }
 }