thingspeak/app/views/pages/home.html.erb

<script type="text/javascript">
  // users timezone offset
  var myOffset = new Date().getTimezoneOffset();

  // converts date format from JSON
  function getChartDate(d) {
    // get the data using javascript's date object (year, month, day, hour, minute, second)
    // months in javascript start at 0, so remember to subtract 1 when specifying the month
    // offset in minutes is converted to milliseconds and subtracted so that chart's x-axis is correct
    return Date.UTC(d.substring(0,4), d.substring(5,7)-1, d.substring(8,10), d.substring(11,13), d.substring(14,16), d.substring(17,19)) - (myOffset * 60000);
  }

  $(document).ready(function() {
    // blank array for holding chart data
    var chartData = [];
    // variable for the date string
    var d;
    // variable for the data point
    var p;
    // variable for the local date in milliseconds
    var localDate;

    // get the data with a webservice call
    $.getJSON('https://api.thingspeak.com/channels/9/field/1.json?callback=?&amp;results=15&amp;offset=0', function(data) {
      // if no access
      if (data == '-1') {
        $('#chart-container').append('This channel is not public.  To embed charts, the channel must be public or a read key must be specified.');
      }

      // iterate through each feed
      $.each(data.feeds, function() {
        p = this.field1;
        // if a numerical value exists add it
        if (!isNaN(parseInt(p))) {
          chartData.push([getChartDate(this.created_at), parseFloat(p)]);
        }
      });

      // specify the chart options
      var chartOptions = {
        chart: {
          renderTo: 'chart-container',
          defaultSeriesType: 'line',
          backgroundColor: '#fff',
          events: {
            load: function() {
              // push data every 15 seconds
              setInterval(function() {

                // get the data with a webservice call
                $.getJSON('https://api.thingspeak.com/channels/9/feed/last.json?callback=?&amp;offset=0', function(data) {
                  p = data.field1;
                  d = getChartDate(data.created_at);
                  last_date = dynamicChart.series[0].data[dynamicChart.series[0].data.length-1].x;

                  // if a numerical value exists and it is a new date, add it
                  if (!isNaN(parseInt(p)) && (d != last_date)) {

                    dynamicChart.series[0].addPoint([d, parseFloat(p)], true, true);
                  }
                });

              }, 15000);
            }
          }
        },
        title: {
          text: ''
        },
        plotOptions: {
          line: {
            color: '#d62020'
          },
          bar: {
            color: '#d62020'
          },
          column: {
            color: '#d62020'
          },
          series: {
            marker: {
              radius: 3
            },
            animation: true
          }
        },
        tooltip: {
          // reformat the tooltips so that local times are displayed
          formatter: function() {
            var d = new Date(this.x + (myOffset*60000));
            return this.series.name + ':<b>' + this.y + '</b><br/>' + d.toDateString() + '<br/>' + d.toTimeString().replace(/\(.*\)/, "");
          }
        },
        xAxis: {
          type: 'datetime',
          title: {
            text: ''
          }
        },
        yAxis: {
          title: {
            text: ''
          }
        },
                          exporting: {
                                  enabled: false
                          },
        legend: {
          enabled: false
        },
        series: [{
          name: data.channel.field1
        }]
      };

      // add the data to the chart
      chartOptions.series[0].data = chartData;

      // set chart labels here so that decoding occurs properly
      chartOptions.title.text = 'Dynamic Light Levels';
      chartOptions.xAxis.title.text = 'Time';
      chartOptions.yAxis.title.text = data.channel.field1;

      // draw the chart
      var dynamicChart = new Highcharts.Chart(chartOptions);

    });

  });

</script>

<div class="row">
  <div class="text-center">
    <%= image_tag 'front.png', :size => '854x144' %>
  </div>
</div>

<br><br><br>

<div class="row">
  <div class="col-sm-6">
    <div id="chart-container" class="center-block" style="width: 500px; height: 260px; padding-left: 20px;"></div>
  </div>
  <div class="col-sm-6">
    <div style="margin-top: 55px;" class="text-center"><a href="http://community.thingspeak.com/tutorials/netduino/create-your-own-web-of-things-using-the-netduino-plus-and-thingspeak/"><%= image_tag 'my_house_status_update.png' %></a></div>
  </div>
</div>

<br><br><br>

<div class="row">

  <div class="col-sm-4">
    <h4 class="breadcrumb">Features</h4>
    <p>
      <ul>
        <li>Open Source API</li>
        <li>Real-time data collection</li>
        <li>Data processing</li>
        <li>Data visualizations</li>
        <li>Location-awareness</li>
        <li>Status context</li>
        <li>Application infrastructure</li>
        <li>Twitter proxy</li>
        <li>Apps</li>
        <li>Plugins</li>
        <li><%= link_to '... more', features_pages_path %></li>
      </ul>
    </p>
  </div>

  <div class="col-sm-4">
    <h4 class="breadcrumb">Applications</h4>
    <p>
      <ul>
        <li>Sensor monitoring</li>
        <li>Energy monitoring</li>
        <li>Connecting devices and systems</li>
        <li>Geo location tracking</li>
        <li>Interfacing with social networks</li>
        <li>RFID transactions</li>
      </ul>
    </p>
    <h4 class="breadcrumb">Who Uses ThingSpeak</h4>
    <p>
      <ul>
        <li>Application developers</li>
        <li>Product integrators</li>
        <li>Web designers</li>
      </ul>
    </p>
  </div>

  <div class="col-sm-4">
    <h4 class="breadcrumb">Get Started</h4>
      <div class="col-pad">
        If you are ready to get started, <span id="feature_signup"> <%= link_to t(:signup), new_account_path %></span> for a free user account.
      </div>
    <h4 class="breadcrumb">Connect</h4>
    <p>
      <ul>
        <li><a href="http://www.twitter.com/thingspeak" title="Follow ThingSpeak on Twitter">Twitter</a></li>
        <li><a href="https://github.com/iobridge/ThingSpeak" title="Open Source Internet of Things Project on GitHub">GitHub</a></li>
        <li><a href="http://community.thingspeak.com" title="Join the ThingSpeak Community">ThingSpeak Community</a></li>
        <li><a href="/docs" title="ThingSpeak API and Apps Documentation">Documentation</a> and <a href="http://community.thingspeak.com/tutorials" title="ThingSpeak Tutorials">Tutorials</a></li>
        <li><a href="mailto:support@thingspeak.com" title="Contact ThingSpeak">Questions</a></li>
      </ul>
    </p>
  </div>

</div>

<br><br><br>

<div class="row">
  <div class="col-sm-offset-2 col-sm-8 col-xs-12">

    <div class="center-block" style="max-width: 600px;">
      <h4><a href="http://community.thingspeak.com/" title="ThingSpeak Community, Blog, and Forum">latest news<a> <a href="http://feeds.feedburner.com/internetofthings/" title="ThingSpeak RSS Feed"><%= image_tag 'icon_rss.gif' %></a></h4>
      <br>

      <% cache("blog-posts-on-homepage", :expires_in => 10.minutes) do %>
        <%= raw blog_entries %>
      <% end %>
    </div>

  </div>
</div>