Live updating of charts

.gitignore

@@ -4,3 +4,4 @@ config/database.config
 .DS_Store
 deps
 ebin
+logs

migrations/trim_esense_names_001.sql

@@ -0,0 +1,3 @@
+-- Remove all double quotes from name
+UPDATE `esense` e SET e.`name` = REPLACE(e.`name`, '"','');
+

src/chart_resource.erl

@@ -8,7 +8,7 @@
 %% API Function Exports
 %% ------------------------------------------------------------------
 
--export([init/1, to_html/2]).
+-export([init/1, to_html/2, to_json/2, content_types_provided/2]).
 
 %% ------------------------------------------------------------------
 %% Header includes
@@ -22,33 +22,57 @@
 
 init([]) -> {ok, undefined}.
 
+content_types_provided(ReqData, State) ->
+    Types = [{"application/json", to_json},{"text/html", to_html}],
+    {Types, ReqData, State}.
+
+
+%% @doc Provides fresh datapoints for the specified chart type
+to_json(ReqData, State) ->
+    LastMaxTimestamp = erlang:list_to_integer(
+                         wrq:get_qs_value("maxValue", ReqData)
+                        ),
+    StartTimestamp = LastMaxTimestamp + 1,
+    EndTimestamp = db_queries:maxESenseTimestamp(),
+    ChartDataType = wrq:get_qs_value("chartDataType", ReqData),
+    Data = chartData(ChartDataType, StartTimestamp, EndTimestamp),
+    Result = proplists:get_value("rows", Data),
+    {mochijson2:encode(Result), ReqData, State}.
+
+%% @doc Render the charts with existing datapoints
 to_html(ReqData, State) ->
     EndTimestamp = db_queries:maxESenseTimestamp(),
     StartTimestamp = EndTimestamp - utils:timestamp({0,1000,0}),
     Charts = [
-              "\"meditation\"", "\"theta\"", "\"highBeta\"",
-              "\"highGamma\"", "\"attention\"", "\"lowBeta\"",
-              "\"delta\"", "\"highAlpha\"", "\"lowGamma\"",
-              "\"lowAlpha\""
+              "meditation", "theta", "highBeta",
+              "highGamma", "attention", "lowBeta",
+              "delta", "highAlpha", "lowGamma",
+              "lowAlpha", "combined", "poorsignal", "blink"
              ],
     ChartsData = lists:map(
-                   fun(C) -> eSenseData(C, StartTimestamp, EndTimestamp) end,
+                   fun(C) -> chartData(C, StartTimestamp, EndTimestamp) end,
                    Charts),
-    Data = [{charts, [
-                      eSenseData(StartTimestamp, EndTimestamp),
-                      blinkData(StartTimestamp, EndTimestamp),
-                      poorSignalData(StartTimestamp, EndTimestamp)
-                     ]
-             ++
-                 ChartsData
-            } ],
+    Data = [{charts, ChartsData} ],
     {ok, Content} = linechart_dtl:render(Data),
     {Content, ReqData, State}.
 
 %% ------------------------------------------------------------------
 %% private Function Definitions
 %% ------------------------------------------------------------------
 
+-spec chartData(iolist(), integer(), integer()) -> list().
+chartData(Type, StartTimestamp, EndTimestamp) ->
+    case Type of
+        "blink" ->
+            blinkData(StartTimestamp, EndTimestamp);
+        "poorsignal" ->
+            poorSignalData(StartTimestamp, EndTimestamp);
+        "combined" ->
+            eSenseData(StartTimestamp, EndTimestamp);
+        ESense ->
+            eSenseData(ESense, StartTimestamp, EndTimestamp)
+    end.
+
 -spec blinkData(integer(), integer()) -> list().
 blinkData(StartTimestamp, EndTimestamp) ->
     DataRows = lists:map(
@@ -66,6 +90,7 @@ blinkData(StartTimestamp, EndTimestamp) ->
             {"width", "1012"},
             {"height", "200"},
             {"title", "Blink"},
+            {"chartDataType", "blink"},
             {"columns", [{ "number", "Timestamp"}, { "number", "strength" }]},
             {"rows", DataRows }
            ],
@@ -88,6 +113,7 @@ poorSignalData(StartTimestamp, EndTimestamp) ->
             {"width", "1024"},
             {"height", "200"},
             {"title", "Poor Signal"},
+            {"chartDataType", "poorsignal"},
             {"columns", [{ "number", "Timestamp"}, { "number", "level" }]},
             {"rows", DataRows }
            ],
@@ -114,6 +140,7 @@ eSenseData(StartTimestamp, EndTimestamp) ->
             {"width", "1024"},
             {"height", "200"},
             {"title", "Combined eSenses"},
+            {"chartDataType", "combined"},
             {"columns", DataColumns2},
             {"rows", DataRows }
            ],
@@ -122,22 +149,29 @@ eSenseData(StartTimestamp, EndTimestamp) ->
 -spec eSenseData(iolist(), integer(), integer()) -> list().
 eSenseData(Esense, StartTimestamp, EndTimestamp) ->
     Res = db_queries:eSense(Esense, StartTimestamp, EndTimestamp),
-    DataColumns1 = re:split(lists:nth(2,lists:nth(1, Res)), ","),
-    DataColumns2 = [{"number", "Timestamp"}] ++ lists:map(fun(H) -> { "number", H } end, DataColumns1),
-    DataRows = lists:map(
-                 fun( R ) ->
-                         {
-                      erlang:integer_to_list(lists:nth(1, R)),
-                      erlang:list_to_integer(erlang:binary_to_list(lists:nth(3, R)))
-                     }
-                 end, Res),
+    case Res of
+        [] ->
+            DataColumns = [{"number", "Timestamp"}],
+            DataRows = [];
+        _ -> 
+            DataCol = re:split(lists:nth(2,lists:nth(1, Res)), ","),
+            DataColumns = [{"number", "Timestamp"}] ++ lists:map(fun(H) -> { "number", H } end, DataCol),
+            DataRows = lists:map(
+                         fun( R ) ->
+                                 {
+                              erlang:integer_to_list(lists:nth(1, R)),
+                              erlang:list_to_integer(erlang:binary_to_list(lists:nth(3, R)))
+                             }
+                         end, Res)
+    end,
     Data = [
             {"hAxis_minValue", StartTimestamp},
             {"hAxis_maxValue", EndTimestamp},
             {"width", "1024"},
             {"height", "200"},
             {"title", Esense},
-            {"columns", DataColumns2},
+            {"chartDataType", Esense},
+            {"columns", DataColumns},
             {"rows", DataRows }
            ],
     Data.

src/database_ser.erl

@@ -118,11 +118,11 @@ encode(Param) when erlang:is_list(Param) ->
             mysql:encode(Param);
         false ->
             string:join(
-              lists:map(fun(P) -> encode(printable(P)) end, Param), ", "
+              lists:map(fun(P) -> encode(P) end, Param), ", "
              )
     end;
 encode(Param) ->
-    mysql:encode(Param).
+    mysql:encode(printable(Param)).
 
 -spec seperator(any()) -> iolist().
 seperator(Param) when erlang:is_list(Param) ->

templates/linechart.dtl

@@ -3,6 +3,7 @@
     <script type="text/javascript" src="https://www.google.com/jsapi"></script>
     <script type="text/javascript">
       google.load("visualization", "1", {packages:["corechart"]});
+      google.load("jquery", "1.4.2");
       google.setOnLoadCallback(drawCharts);
       function drawCharts() {
 
@@ -30,6 +31,20 @@
         var chart = new google.visualization.LineChart(document.getElementById('chart_div{{forloop.counter0 }}'));
         chart.draw(data, options);
 
+        var maxValue = {{ chart.hAxis_maxValue }};
+
+        setInterval(function() {
+            $.getJSON('/chart?esense={{ chart.chartDataType }}&maxValue=' + maxValue, function(rows) {
+                    for(var index in rows) {
+                        data.addRow([parseInt(index), rows[index]]);
+                        maxValue = [parseInt(index)];
+                    }
+                    chart.draw(data);
+                    }
+            )
+        }, 
+        200);
+
         {% endfor %}        
       }
     </script>

test/test_SUITE.erl

@@ -0,0 +1,6 @@
+-module(test_SUITE).
+-include_lib("common_test/include/ct.hrl").
+-export([all/0]).
+-export([]).
+
+all() -> [].