Add comment describing data. Do some type checking.

cmd/scollector/collectors/google_analytics.go

@@ -60,19 +60,24 @@ func c_google_analytics(clientid string, secret string, tokenstr string, sites [
 			offset = 1
 		}
 		time := time.Now().Add(time.Duration(-1*offset) * time.Minute).Unix()
+		pageviews := 0
 		// Iterates through the response data and returns the time slice we
 		// actually care about when we find it.
-		for _, v := range data.Rows {
-			minute, err := strconv.Atoi(v[0])
+		for _, row := range data.Rows {
+			// row == [2]string{"0", "123"}
+			// First item is the minute, second is the data (pageviews in this case)
+			minute, err := strconv.Atoi(row[0])
 			if err != nil {
 				return md, fmt.Errorf("Error parsing GA data: %s", err)
 			}
 			if minute == offset {
-				value = v[1]
+				if pageviews, err = strconv.Atoi(row[1]); err != nil {
+					return md, fmt.Errorf("Error parsing GA data: %s", err)
+				}
 				break
 			}
 		}
-		AddTS(&md, "google.analytics.realtime.pageviews", time, value, opentsdb.TagSet{"site": site.Name}, metadata.Gauge, metadata.Count, "Number of pageviews tracked by GA in one minute")
+		AddTS(&md, "google.analytics.realtime.pageviews", time, pageviews, opentsdb.TagSet{"site": site.Name}, metadata.Gauge, metadata.Count, "Number of pageviews tracked by GA in one minute")
 	}
 
 	return md, err