replace TSDASH_PLOT_DIR envar with plot.tsdash.dir property

conf/tsdash.properties

@@ -2,12 +2,13 @@
 hbase.tsdash.datatable=tsdb
 hbase.tsdash.uidtable=tsdb-uid
 
+hbase.zookeeper.quorum=localhost
+
 # urlpattern is the pattern used to generate URLs of the plots generated by running Gnuplot
 # The parameters are: 
 # - %h host
-# - %p port
+# - %p port; by default is 8090
 # - %f filename
 plot.tsdash.urlpattern=http://%h:%p/plots/%f
 
-hbase.zookeeper.quorum=localhost
-
+plot.tsdash.dir=/var/www/tsdash/plots

server/.gitignore

@@ -1 +1,2 @@
 build/
+bin/

server/src/com/facebook/tsdb/tsdash/server/TsdbServlet.java

@@ -48,6 +48,9 @@ public class TsdbServlet extends HttpServlet {
     public static final String URL_PATTERN_PARAM = "plot.tsdash.urlpattern";
     public static final String DEFAULT_URL_PATTERN = "http://%h:%p/plots/%f";
     public static final int DEFAULT_PLOT_PORT = 8090;
+    public static final String PLOTS_DIR_PARAM = "plot.tsdash.dir";
+    public static final String DEFAULT_PLOTS_DIR = "/tmp";
+    public static String plotsDir = DEFAULT_PLOTS_DIR;
     private static String URLPattern = DEFAULT_URL_PATTERN;
     private String hostname = null;
 
@@ -60,6 +63,9 @@ private static void loadConfiguration() {
             URLPattern = tsdbConf.getProperty(URL_PATTERN_PARAM,
                     DEFAULT_URL_PATTERN);
             logger.info("URL pattern: " + URLPattern);
+            plotsDir = tsdbConf.getProperty(PLOTS_DIR_PARAM,
+            		DEFAULT_PLOTS_DIR);
+            logger.info("Plots are being written to: " + plotsDir);
         } catch (FileNotFoundException e) {
             System.err.println("Cannot find " + PROPERTIES_FILE);
         } catch (IOException e) {

server/src/com/facebook/tsdb/tsdash/server/gnuplot/GnuplotProcess.java

@@ -24,6 +24,7 @@
 import java.util.ArrayList;
 import java.util.Random;
 
+import com.facebook.tsdb.tsdash.server.TsdbServlet;
 import com.facebook.tsdb.tsdash.server.model.Metric;
 
 public abstract class GnuplotProcess {
@@ -33,11 +34,6 @@ public abstract class GnuplotProcess {
     public static final String BASH = "/bin/bash";
     public static final String GNUPLOT = "/usr/local/bin/gnuplot";
     private static Random rand = new Random();
-    private static String outputDir;
-
-    static {
-        outputDir = System.getenv(OUTPUT_DIR_ENV);
-    }
 
     protected Process gnuplot;
     protected BufferedWriter gnuplotStdin;
@@ -47,10 +43,6 @@ public abstract class GnuplotProcess {
     protected int plotNo = 0;
 
     public GnuplotProcess() throws Exception {
-        if (outputDir == null) {
-            throw new Exception("Output dir not specified. Please set "
-                    + OUTPUT_DIR_ENV + " envirnonment variable");
-        }
         id = rand.nextInt();
         if (id < 0) {
             id = - id;
@@ -68,11 +60,11 @@ protected String getPipeFilename(int pipeNo) {
     }
 
     protected static String noDataFilename() {
-        return outputDir + "/no_data.jpg";
+        return TsdbServlet.plotsDir + "/no_data.jpg";
     }
 
     protected String getOutputFilename(GnuplotOptions options) {
-        return String.format("%s/%d-%d.%s", outputDir, id, plotNo,
+        return String.format("%s/%d-%d.%s", TsdbServlet.plotsDir, id, plotNo,
                 options.getTerminal());
     }