Merge pull request #92 from savaka2/update-weather-sample-extension

Update weather sample extension

weather_extension.js

@@ -1,39 +1,130 @@
 /* Extension demonstrating a blocking reporter block */
 /* Sayamindu Dasgupta <sayamindu@media.mit.edu>, May 2014 */
+/* Kreg Hanning <khanning@media.mit.edu>, July 2016 */
 
+(function(ext) {
+  // You will need to obtain an API key to query
+  // the OpenWeatherMap.org server
+  // https://openweathermap.org/api
+  var APPID = 'INSERT_API_KEY_HERE';
 
-new (function() {
+  var cacheDuration = 1800000 //ms, 30 minutes
-    var ext = this;
+  var cachedTemps = {};
 
-    // Cleanup function when the extension is unloaded
+  var units = 'imperial';
-    ext._shutdown = function() {};
 
-    // Status reporting code
+  function getWeatherData(weatherData, type) {
-    // Use this to report missing hardware, plugin or unsupported browser
+    var val = null;
-    ext._getStatus = function() {
+    switch (type) {
-        return {status: 2, msg: 'Ready'};
+      case 'temperature':
-    };
+        val = weatherData.main.temp;
+        if (units === 'metric')
+          val = (val - 32) * (5/9)
+        val = Math.round(val);
+        break;
+      case 'weather':
+        val = weatherData.weather[0].description;
+        break;
+      case 'humidity':
+        val = weatherData.main.humidity;
+        break;
+      case 'wind speed':
+        val = weatherData.wind.speed;
+        if (units === 'imperial')
+          val *= 2.23694;
+        if (Math.round(val) !== val)
+          val = val.toFixed(1);
+        break;
+      case 'cloudiness':
+        val = weatherData.clouds.all;
+        break;
+    }
+    return(val);
+  }
 
-    ext.get_temp = function(location, callback) {
+  function fetchWeatherData(location, callback) {
-        // Make an AJAX call to the Open Weather Maps API
-        $.ajax({
-              url: 'http://api.openweathermap.org/data/2.5/weather?q='+location+'&units=imperial',
-              dataType: 'jsonp',
-              success: function( weather_data ) {
-                  // Got the data - parse it and return the temperature
-                  temperature = weather_data['main']['temp'];
-                  callback(temperature);
-              }
-        });
-    };
 
-    // Block and block menu descriptions
+    if (location in cachedTemps &&
-    var descriptor = {
+        Date.now() - cachedTemps[location].time < cacheDuration) {
-        blocks: [
+      //Weather data is cached
-            ['R', 'current temperature in city %s', 'get_temp', 'Boston, MA'],
+      callback(cachedTemps[location].data);
-        ]
+      return;
-    };
+    }
 
-    // Register the extension
+    // Make an AJAX call to the Open Weather Maps API
-    ScratchExtensions.register('Weather extension', descriptor, ext);
+    $.ajax({
-})();
+      url: 'http://api.openweathermap.org/data/2.5/weather',
+      data: {q: location, units: 'imperial', appid: APPID},
+      dataType: 'jsonp',
+      success: function(weatherData) {
+        //Received the weather data. Cache and return the data.
+        cachedTemps[location] = {data: weatherData, time: Date.now()};
+        callback(weatherData);
+      }
+    });
+  }
+
+  // Cleanup function when the extension is unloaded
+  ext._shutdown = function() {};
+
+  // Status reporting code
+  // Use this to report missing hardware, plugin or unsupported browser
+  ext._getStatus = function() {
+    return {status: 2, msg: 'Ready'};
+  };
+
+  ext.getWeather = function(type, location, callback) {
+    fetchWeatherData(location, function(data) {
+      var val = getWeatherData(data, type);
+      callback(val);
+    });
+  };
+
+  ext.whenWeather = function(type, location, op, val) {
+    if (!cachedTemps[location]) {
+      //Weather data not cached
+      //Fetch it and return false for now
+      fetchWeatherData(location, function(){});
+      return false;
+    }
+    //Weather data is cached, no risk of blocking
+    var data = getWeatherData(cachedTemps[location].data, type);
+    switch (op) {
+      case '<':
+        return (data < val);
+      case '=':
+        return (data == val);
+      case '>':
+        return (data > val);
+    }
+  };
+
+  ext.setUnits = function(format) {
+    units = format;
+    return;
+  };
+
+  ext.getUnits = function() {
+    return units;
+  };
+
+  // Block and block menu descriptions
+  var descriptor = {
+    blocks: [
+      ['R', '%m.reporterData in %s', 'getWeather', 'temperature', 'Boston, MA'],
+      ['h', 'when %m.eventData in %s is %m.ops %n', 'whenWeather', 'temperature', 'Boston, MA', '>', 80],
+      [' ', 'set units to %m.units', 'setUnits', 'imperial'],
+      ['r', 'unit format', 'getUnits']
+    ],
+    menus: {
+      reporterData: ['temperature', 'weather', 'humidity', 'wind speed', 'cloudiness'],
+      eventData: ['temperature', 'humidity', 'wind speed', 'cloudiness'],
+      ops: ['>','=', '<'],
+      units: ['imperial', 'metric']
+    }
+  };
+
+  // Register the extension
+  ScratchExtensions.register('Weather extension', descriptor, ext);
+
+})({});