added year popularity record retrieval functionality

googletrendsgame/server/trendsAPI.js

@@ -1,6 +1,38 @@
 const googt = require('google-trends-api');
 const Promise = require('promise');
-const DAY = 1000 * 60 * 60 * 24;
+const DAY = 1000 * 60 * 60 * 24; // 1 day in milliseconds
+const YEAR = DAY * 365; // 1 year in milliseconds
+const GEO = 'US'; //the scope of the trends
+
+
+/**
+desc: helper function for getYearStats, gets list of popularity for days in
+the month.
+*/
+function getMonthStats(word, month){
+
+  return new Promise(function(resolve, reject){
+    //set up query for 1 month length
+    googt.interestOverTime({
+      keyword:word,
+      startTime:new Date(Date.now() - (YEAR * month/12)),
+      endTime:new Date(Date.now() - (YEAR * (month-1)/12))
+    }).then(function(results){
+      //parse the json, fill return array w tuples of date + value
+      var times = JSON.parse(results).default.timelineData;
+      var ret = [];
+      for(var i = 0; i < times.length; ++i){
+        var tup = new Object();
+        tup.time = times[i].formattedTime;
+        tup.value = times[i].value[0];
+        ret[i] = tup;
+
+      }
+      resolve(ret);
+    });
+  });
+}
+
 module.exports=
     {
         /*
@@ -11,9 +43,11 @@ module.exports=
             //must be a promise since call to trends API is async
             return new Promise(function(resolve, reject){
 
-            //specifies the keyword, time interval, and granularity
+            //specifies the keyword, time interval, granularity, and region
             googt.interestOverTime({keyword:word,
-              startTime:new Date(Date.now() - DAY),granularTimeResolution:true})
+              startTime:new Date(Date.now() - DAY),granularTimeResolution:true,
+              geo:GEO
+            })
               .then(function(results){
                 //turn into json object
                 data = JSON.parse(results).default.timelineData;
@@ -21,7 +55,6 @@ module.exports=
                 //add up values
                 var total = 0;
                 data.forEach(function(element){
-                  console.log(element.formattedTime + " " + element.value[0]);
                   total += element.value[0];
                 })
 
@@ -31,5 +64,23 @@ module.exports=
                 reject("Google Trends Query Failed");
               });
             });
+        },
+
+        /**
+        desc: returns a list of tuples (date, value) representing word's
+        popularity for the past year
+        */
+        getYearStats: async function(word){
+          var ret = [];
+
+            for (var i = 9; i > 0; --i) {
+              await getMonthStats(word,i).then(function(data){
+                ret = ret.concat(data);
+              });
+              console.log(i);
+            }
+
+            return ret;
         }
+
      };