Add support for multiple DS data sources and update all charts when a selection is made. Only allow one ongoing rrd download

2 files changed, 138 insertions, 67 deletions

diff --git a/index.html b/index.html
index 7204af5..550e4d3 100644
--- a/index.html
+++ b/index.html
@@ -16,7 +16,7 @@
         <script type="text/javascript" src="jrrd.js"></script>
         <script type="text/javascript">
 
-        var graphOptions = {
+        var baseOptions = {
             grid: {
                 clickable: true
             },
@@ -24,12 +24,10 @@
                 mode: 'x'
             },
             series: {
-                stack: true,
                 points: { show: false },
                 lines: {
                     show: true,
                     steps: false,
-                    fill: 0.5,
                     shadowSize: 0,
                     lineWidth: 1
                 },
@@ -40,71 +38,90 @@
             }
         };
 
-        var Chart = function(template) {
-            var self = this;
+        var fillOptions = jQuery.extend(true, {
+            series: {
+                stack: true,
+                lines: {
+                    fill: 0.5
+                }
+            }
+        }, baseOptions);
 
-            this.template = template;
-            this.data = [];
+        function cpuChartFactory(template) {
+            var c = new jrrd.Chart(template, fillOptions);
+            data = 'cpu-user.rrd  cpu-system.rrd  cpu-wait.rrd'.split('  ').reverse();
 
-            this.template.bind('plotclick', function(event, pos, item) {
-                if (item) {
-                    console.log(['X: ' + new Date(item.datapoint[0]),
-                                 'Y: ' + item.datapoint[1]]);
-                }
+            jQuery.each(data, function(i, el) {
+                var url = 'data/localhost/cpu-0/' + el;
+                var label = el.split('.')[0].split('-')[1];
+                c.addData(label, new jrrd.RrdQueryRemote(url));
             });
+            return c;
+        }
 
-            this.template.bind("plotselected", function(event, ranges) {
-                var startTime = new Date(ranges.xaxis.from);
-                var endTime = new Date(ranges.xaxis.to);
-                self.draw(startTime, endTime);
-                console.log("You selected " + startTime + " to " + endTime);
+        function memoryChartFactory(template) {
+            var c = new jrrd.Chart(template, fillOptions);
+            data = 'memory-free.rrd memory-cached.rrd memory-used.rrd memory-buffered.rrd'.split(' ').reverse();
+
+            jQuery.each(data, function(i, el) {
+                var url = 'data/localhost/memory/' + el;
+                var label = el.split('.')[0].split('-')[1];
+                c.addData(label, new jrrd.RrdQueryRemote(url));
             });
+            return c;
+        }
+
+        var RrdQueryDsProxy = function(rrdQuery, dsId) {
+            this.rrdQuery = rrdQuery;
+            this.dsId = dsId;
         };
 
-        Chart.prototype.addData = function(label, db) {
-            this.data.push([label, db]);
+        RrdQueryDsProxy.prototype.getData = function(startTime, endTime) {
+            return this.rrdQuery.getData(startTime, endTime, this.dsId);
         };
 
-        Chart.prototype.draw = function(startTime, endTime) {
-            var self = this;
+        function loadChartFactory(template) {
+            var c = new jrrd.Chart(template, baseOptions);
+            var data = new jrrd.RrdQueryRemote('data/localhost/load/load.rrd');
+            var rrdDSs = ['shortterm', 'midterm', 'longterm'];
+            jQuery.each(rrdDSs, function(i, rrdDS) {
+                c.addData(rrdDS, new RrdQueryDsProxy(data, rrdDS));
+            });
+            return c;
+        }
 
-            var results = [];
-            for(var i=0; i<this.data.length; i++) {
-                results.push(this.data[i][1].getData(startTime, endTime));
-            }
+        $(function() {
+            var chartTemplate = $('.chart').remove();
+            var charts = [
+                loadChartFactory(
+                    chartTemplate.clone().appendTo('.charts')),
 
-            return MochiKit.Async.gatherResults(results)
-                   .addCallback(
-                    function(data) {
-                        for(var i=0; i<data.length; i++) {
-                            data[i].label = self.data[i][0];
-                        }
-                        var plot = $.plot(self.template, data, graphOptions);
-                    })
-                   .addErrback(
-                    function(failure) {
-                        $('.container').text('error: ' + failure.message);
-                    });
-        };
+                cpuChartFactory(
+                    chartTemplate.clone().appendTo('.charts')),
 
-        $(function() {
-            var c = new Chart($('.container'));
-            //data = 'memory-free.rrd memory-cached.rrd memory-used.rrd memory-buffered.rrd'.split(' ').reverse();
-            data = 'cpu-user.rrd  cpu-system.rrd  cpu-wait.rrd'.split('  ').reverse();
+                memoryChartFactory(
+                    chartTemplate.clone().appendTo('.charts'))
+            ];
 
-            jQuery.each(data, function(i, el) {
-                var url = 'data/localhost/cpu-0/' + el;
-                var label = el.split('.')[0].split('-')[1];
-                c.addData(label, new jrrd.RrdQueryRemote(url));
+            jQuery.each(charts, function(i, chart) {
+                chart.draw(new Date('7 April 2010 09:30:00'),
+                           new Date('7 April 2010 15:00:00'));
             });
 
-            c.draw(new Date('7 April 2010 09:30:00'),
-                   new Date('7 April 2010 15:00:00'));
+            $('.chart').bind("plotselected", function(event, ranges) {
+                var startTime = new Date(ranges.xaxis.from);
+                var endTime = new Date(ranges.xaxis.to);
+                jQuery.each(charts, function(i, chart) {
+                    chart.draw(startTime, endTime);
+                });
+            });
         });
         </script>
     </head>
 
     <body>
-        <div class="container" style="width:100%; height:200px;"></div>
+        <div class="charts">
+            <div class="chart" style="width:800px; height:200px; float: right; clear: right;"></div>
+        </div>
     </body>
 </html>
diff --git a/jrrd.js b/jrrd.js
index 44fdb95..3f2c69b 100644
--- a/jrrd.js
+++ b/jrrd.js
@@ -51,7 +51,6 @@ jrrd.RrdQuery.prototype.getData = function(startTime, endTime, dsId) {
         dsId = 0;
     }
     var ds = this.rrd.getDS(dsId);
-
     var consolidationFunc = 'AVERAGE';
     var lastUpdated = this.rrd.getLastUpdate();
 
@@ -77,12 +76,12 @@ jrrd.RrdQuery.prototype.getData = function(startTime, endTime, dsId) {
         throw new Error('Unrecognised consolidation function: ' + consolidationFunc);
     }
 
-    startRow = rraRowCount - parseInt((lastUpdated - startTimestamp)/step);
-    endRow = rraRowCount - parseInt((lastUpdated - endTimestamp)/step);
+    var startRow = rraRowCount - parseInt((lastUpdated - startTimestamp)/step);
+    var endRow = rraRowCount - parseInt((lastUpdated - endTimestamp)/step);
 
-    flotData = [];
-    timestamp = firstUpdated + (startRow - 1) * step;
-    dsIndex = ds.getIdx();
+    var flotData = [];
+    var timestamp = firstUpdated + (startRow - 1) * step;
+    var dsIndex = ds.getIdx();
     for (var i=startRow; i<=endRow; i++) {
         var val = bestRRA.getEl(i, dsIndex);
         flotData.push([timestamp*1000.0, val]);
@@ -94,30 +93,85 @@ jrrd.RrdQuery.prototype.getData = function(startTime, endTime, dsId) {
 
 jrrd.RrdQueryRemote = function(url) {
     this.url = url;
-    this.rrd = null;
+    this.lastUpdate = 0;
+    this._download = null;
 };
 
-jrrd.RrdQueryRemote.prototype.getData = function(startTime, endTime) {
+jrrd.RrdQueryRemote.prototype.getData = function(startTime, endTime, dsId) {
     var endTimestamp = endTime.getTime()/1000;
 
-    var d, self = this;
-    if(!this.rrd || this.rrd.getLastUpdate() < endTimestamp) {
-        d = jrrd.downloadBinary(this.url)
+    var self = this;
+
+    // Download the rrd if there has never been a download or if the last
+    // completed download had a lastUpdated timestamp less than the requested
+    // end time.
+    // Don't start another download if one is already in progress.
+    if(!this._download || (this._download.fired > -1 && this.lastUpdate < endTimestamp )) {
+        this._download = jrrd.downloadBinary(this.url)
                 .addCallback(
                     function(binary) {
+                        // Upon successful download convert the resulting binary
+                        // into an RRD file and pass it on to the next callback
+                        // in the chain.
                         var rrd = new RRDFile(binary);
-                        self.rrd = rrd;
+                        self.lastUpdate = rrd.getLastUpdate();
                         return rrd;
                     });
-    } else {
-        d = new MochiKit.Async.Deferred()
-        d.callback(this.rrd);
     }
 
-    d.addCallback(
+    // Set up a deferred which will call getData on the local RrdQuery object
+    // returning a flot compatible data object to the caller.
+    var ret = new MochiKit.Async.Deferred().addCallback(
         function(rrd) {
-            return new jrrd.RrdQuery(rrd).getData(startTime, endTime);
+            return new jrrd.RrdQuery(rrd).getData(startTime, endTime, dsId);
         });
 
-    return d;
+    // Add a pair of callbacks to the current download which will callback the
+    // result which we setup above.
+    this._download.addCallbacks(
+        function(res) {
+            ret.callback(res);
+            return res;
+        },
+        function(err) {
+            ret.errback(err);
+            return err;
+        });
+
+    return ret;
+};
+
+
+jrrd.Chart = function(template, options) {
+    var self = this;
+
+    this.template = template;
+    this.options = options;
+    this.data = [];
+};
+
+jrrd.Chart.prototype.addData = function(label, db) {
+    this.data.push([label, db]);
+};
+
+jrrd.Chart.prototype.draw = function(startTime, endTime) {
+    var self = this;
+
+    var results = [];
+    for(var i=0; i<this.data.length; i++) {
+        results.push(this.data[i][1].getData(startTime, endTime));
+    }
+
+    return MochiKit.Async.gatherResults(results)
+            .addCallback(
+                function(data) {
+                    for(var i=0; i<data.length; i++) {
+                        data[i].label = self.data[i][0];
+                    }
+                    var plot = $.plot(self.template, data, self.options);
+                })
+            .addErrback(
+                function(failure) {
+                    self.template.text('error: ' + failure.message);
+                });
 };