Weather API Call

main.go

package main

import (
	"encoding/json"
	"io/ioutil"
	"log"
	"net/http"
	"strconv"
	"sync"
	"time"

	"github.com/gin-gonic/gin"
)

var waitGrp sync.WaitGroup

type Weather struct {
	Latitude  float64 `json:"latitude"`
	Longitude float64 `json:"longitude"`
	Timezone  string  `json:"timezone"`
	Daily     struct {
		Data []struct {
			Time                        int     `json:"time"`
			Summary                     string  `json:"summary"`
			Icon                        string  `json:"icon"`
			SunriseTime                 int     `json:"sunriseTime"`
			SunsetTime                  int     `json:"sunsetTime"`
			MoonPhase                   float64 `json:"moonPhase"`
			PrecipIntensity             float64 `json:"precipIntensity"`
			PrecipIntensityMax          float64 `json:"precipIntensityMax"`
			PrecipIntensityMaxTime      int     `json:"precipIntensityMaxTime"`
			PrecipProbability           float64 `json:"precipProbability"`
			PrecipAccumulation          float64 `json:"precipAccumulation"`
			PrecipType                  string  `json:"precipType"`
			TemperatureHigh             float64 `json:"temperatureHigh"`
			TemperatureHighTime         int     `json:"temperatureHighTime"`
			TemperatureLow              float64 `json:"temperatureLow"`
			TemperatureLowTime          int     `json:"temperatureLowTime"`
			ApparentTemperatureHigh     float64 `json:"apparentTemperatureHigh"`
			ApparentTemperatureHighTime int     `json:"apparentTemperatureHighTime"`
			ApparentTemperatureLow      float64 `json:"apparentTemperatureLow"`
			ApparentTemperatureLowTime  int     `json:"apparentTemperatureLowTime"`
			DewPoint                    float64 `json:"dewPoint"`
			Humidity                    float64 `json:"humidity"`
			Pressure                    float64 `json:"pressure"`
			WindSpeed                   float64 `json:"windSpeed"`
			WindGust                    float64 `json:"windGust"`
			WindGustTime                int     `json:"windGustTime"`
			WindBearing                 int     `json:"windBearing"`
			CloudCover                  float64 `json:"cloudCover"`
			UvIndex                     int     `json:"uvIndex"`
			UvIndexTime                 int     `json:"uvIndexTime"`
			Visibility                  float64 `json:"visibility"`
			Ozone                       float64 `json:"ozone"`
			TemperatureMin              float64 `json:"temperatureMin"`
			TemperatureMinTime          int     `json:"temperatureMinTime"`
			TemperatureMax              float64 `json:"temperatureMax"`
			TemperatureMaxTime          int     `json:"temperatureMaxTime"`
			ApparentTemperatureMin      float64 `json:"apparentTemperatureMin"`
			ApparentTemperatureMinTime  int     `json:"apparentTemperatureMinTime"`
			ApparentTemperatureMax      float64 `json:"apparentTemperatureMax"`
			ApparentTemperatureMaxTime  int     `json:"apparentTemperatureMaxTime"`
		} `json:"data"`
	} `json:"daily"`
	Flags struct {
		Sources     []string `json:"sources"`
		IsdStations []string `json:"isd-stations"`
		Units       string   `json:"units"`
	} `json:"flags"`
	Offset int `json:"offset"`
}

func getWeatherAtTime(waitGrp *sync.WaitGroup, workQueue chan Weather, lat string, long string, daysBack int) {
	log.Println("Working for time")

	urlDarkSky := "https://api.darksky.net/forecast/"
	secretKey := "8639c348aac30cef51ba318d5e8783e1"
	tailUrl := "?exclude=hourly,currently,minutely,alerts,flag"

	timePoint := time.Now().Unix() - (int64(daysBack) * 60 * 60 * int64(24))
	timeStr := strconv.FormatInt(timePoint, 10)
	log.Println(timeStr)
	requestUrl := urlDarkSky + secretKey + "/" + lat + "," + long + "," + timeStr + tailUrl
	log.Printf("Lat=%s, Long=%s Weather Requested.", lat, long)

	log.Println(requestUrl)
	weatherData, err := http.Get(requestUrl)
	if err != nil {
		log.Println(err)
		return
	}
	data, _ := ioutil.ReadAll(weatherData.Body)
	weatherData.Body.Close()
	var weatherObject Weather
	err = json.Unmarshal(data, &weatherObject)
	if err != nil {
		log.Fatal(err)
	}
	workQueue <- weatherObject
	waitGrp.Done()
}

func getWeather(cntx *gin.Context) {
	lat := cntx.Params.ByName("lat")
	long := cntx.Params.ByName("long")
	//weatherTimeMap := make(map[string]string)
	log.Printf("Lat=%s, Long=%s Weather Requested.", lat, long)

	weatherWorkQueue := make(chan Weather, 10)
	log.Println("Starting Loop")
	for i := 6; i >= 0; i-- {
		log.Printf("Request %d days ago", i)
		waitGrp.Add(1)
		go getWeatherAtTime(&waitGrp, weatherWorkQueue, lat, long, i)
	}
	log.Println("After Loop - Waiting")
	waitGrp.Wait()
	log.Println("Done Waiting")
	close(weatherWorkQueue)
	var weatherDays = make([]Weather, 0)
	cnt := 0
	for weatherDay := range weatherWorkQueue {
		cnt++
		log.Printf("Working on another WeatherDay %d", cnt)
		weatherDays = append(weatherDays, weatherDay)
		log.Printf("Finished %d", cnt)
	}
	//TODO Handle Sort Order from Async Callsw
	log.Println("Weather Array")
	returnWeather, _ := json.Marshal(&weatherDays)
	log.Println(string(returnWeather))
	cntx.JSON(http.StatusOK, string(returnWeather))
}

func main() {
	log.Println("Starting GoLang Weather API Service.")

	routes := gin.Default()

	versionRoutes := routes.Group("/api/v1")
	{
		weatherRoutes := versionRoutes.Group("/weather")
		{
			weatherRoutes.GET("/:lat/:long", getWeather)
		}
	}

	routes.Run(":3001")

	log.Println("Ending GoLang Weather API Services.")
}