Add openmeteo support

backends/open-meteo.com.go

@@ -0,0 +1,227 @@
+package backends
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"regexp"
+	"strings"
+	"time"
+
+	"github.com/schachmat/wego/iface"
+)
+
+type openmeteoConfig struct {
+	apiKey   string
+	language string
+	debug    bool
+}
+
+type curCond struct {
+	Time                int64    `json:"time"`
+	Interval            int      `json:"interval"`
+	Temperature2M       *float32 `json:"temperature_2m"`
+	ApparentTemperature *float32 `json:"apparent_temperature"`
+	IsDay               int      `json:"is_day"`
+	WeatherCode         int      `json:"weather_code"`
+	WindDirection10M    *int     `json:"wind_direction_10m"`
+}
+
+type Daily struct {
+	Time                   []int64    `json:"time"`
+	WeatherCode            []int      `json:"weather_code"`
+	Temperature2MMax       []*float32 `json:"temperature_2m_max"`
+	ApparentTemperatureMax []*float32 `json:"apparent_temperature_max"`
+	Sunrise                []int64    `json:"sunrise"`
+	Sunset                 []int64    `json:"sunset"`
+}
+type HourlyUnits struct {
+	Time                string `json:"time"`
+	Temperature2M       string `json:"temperature_2m"`
+	ApparentTemperature string `json:"apparent_temperature"`
+	WeatherCode         string `json:"weather_code"`
+}
+type Hourly struct {
+	Time                []int64    `json:"time"`
+	Temperature2M       []*float32 `json:"temperature_2m"`
+	ApparentTemperature []*float32 `json:"apparent_temperature"`
+	WeatherCode         []int      `json:"weather_code"`
+	WindDirection10M    []*int     `json:"wind_direction_10m"`
+}
+
+type openmeteoResponse struct {
+	Latitude             float64 `json:"latitude"`
+	Longitude            float64 `json:"longitude"`
+	GenerationtimeMs     float64 `json:"generationtime_ms"`
+	UtcOffsetSeconds     int     `json:"utc_offset_seconds"`
+	Timezone             string  `json:"timezone"`
+	TimezoneAbbreviation string  `json:"timezone_abbreviation"`
+	Elevation            float64 `json:"elevation"`
+	CurrentUnits         struct {
+		Time                string `json:"time"`
+		Interval            string `json:"interval"`
+		Temperature2M       string `json:"temperature_2m"`
+		ApparentTemperature string `json:"apparent_temperature"`
+		IsDay               string `json:"is_day"`
+		WeatherCode         string `json:"weather_code"`
+	} `json:"current_units"`
+	Current     curCond     `json:"current"`
+	HourlyUnits HourlyUnits `json:"hourly_units"`
+	Hourly      Hourly      `json:"hourly"`
+	DailyUnits  struct {
+		Time                   string `json:"time"`
+		WeatherCode            string `json:"weather_code"`
+		Temperature2MMax       string `json:"temperature_2m_max"`
+		ApparentTemperatureMax string `json:"apparent_temperature_max"`
+		Sunrise                string `json:"sunrise"`
+		Sunset                 string `json:"sunset"`
+	} `json:"daily_units"`
+	Daily Daily
+}
+
+const (
+	openmeteoURI = "https://api.open-meteo.com/v1/forecast?"
+)
+
+var (
+	codemap = map[int]iface.WeatherCode{
+		0:  iface.CodeSunny,
+		1:  iface.CodePartlyCloudy,
+		2:  iface.CodePartlyCloudy,
+		3:  iface.CodePartlyCloudy,
+		45: iface.CodeFog,
+		48: iface.CodeFog,
+		51: iface.CodeLightRain,
+		53: iface.CodeLightRain,
+		55: iface.CodeLightRain,
+		56: iface.CodeLightSleet,
+		57: iface.CodeLightSleet,
+		61: iface.CodeLightShowers,
+		63: iface.CodeLightShowers,
+		65: iface.CodeLightShowers,
+		66: iface.CodeHeavyRain,
+		67: iface.CodeHeavyRain,
+	}
+)
+
+func (opmeteo *openmeteoConfig) Setup() {
+	flag.StringVar(&opmeteo.apiKey, "openmeteo-api-key", "", "openmeteo backend: the api `KEY` to use if commercial usage")
+	flag.BoolVar(&opmeteo.debug, "openmeteo-debug", false, "openmeteo backend: print raw requests and responses")
+}
+
+func (opmeteo *openmeteoConfig) parseDaily(dailyInfo Hourly) []iface.Day {
+	var forecast []iface.Day
+	var day *iface.Day
+
+	for ind, dayTime := range dailyInfo.Time {
+
+		cond := new(iface.Cond)
+
+		cond.Code = codemap[dailyInfo.WeatherCode[ind]]
+		cond.TempC = dailyInfo.Temperature2M[ind]
+		cond.FeelsLikeC = dailyInfo.ApparentTemperature[ind]
+		cond.Time = time.Unix(dayTime, 0)
+		cond.WinddirDegree = dailyInfo.WindDirection10M[ind]
+
+		if day == nil {
+			day = new(iface.Day)
+			day.Date = cond.Time
+		}
+		if day.Date.Day() == cond.Time.Day() {
+			day.Slots = append(day.Slots, *cond)
+		}
+		if day.Date.Day() != cond.Time.Day() {
+			forecast = append(forecast, *day)
+
+			day = new(iface.Day)
+			day.Date = cond.Time
+			day.Slots = append(day.Slots, *cond)
+		}
+	}
+
+	return forecast
+}
+
+func parseCurCond(current curCond) (ret iface.Cond) {
+
+	ret.Time = time.Unix(current.Time, 0)
+
+	ret.Code = iface.CodeUnknown
+	if val, ok := codemap[current.WeatherCode]; ok {
+		ret.Code = val
+	}
+
+	ret.TempC = current.Temperature2M
+	ret.FeelsLikeC = current.ApparentTemperature
+	ret.WinddirDegree = current.WindDirection10M
+	return ret
+
+}
+
+func (opmeteo *openmeteoConfig) Fetch(location string, numdays int) iface.Data {
+	var ret iface.Data
+	var params []string
+	var loc string
+
+	if numdays <= 0 {
+		log.Fatal("Number of days less than 1 ")
+	}
+
+	if matched, err := regexp.MatchString(`^-?[0-9]*(\.[0-9]+)?,-?[0-9]*(\.[0-9]+)?$`, location); matched && err == nil {
+		s := strings.Split(location, ",")
+		loc = fmt.Sprintf("latitude=%s&longitude=%s", s[0], s[1])
+	}
+	if len(location) > 0 {
+		params = append(params, loc)
+	}
+	params = append(params, "current=temperature_2m,apparent_temperature,is_day,weather_code,wind_direction_10m")
+	params = append(params, "hourly=temperature_2m,apparent_temperature,weather_code,wind_direction_10m")
+	params = append(params, "daily=weather_code,temperature_2m_max,apparent_temperature_max,sunrise,sunset")
+	params = append(params, fmt.Sprintf("timeformat=unixtime&forecast_days=%d", numdays))
+
+	requri := openmeteoURI + strings.Join(params, "&")
+
+	res, err := http.Get(requri)
+	if err != nil {
+		log.Fatal("Unable to get weather data: ", err)
+	} else if res.StatusCode != 200 {
+		log.Fatal("Unable to get weather data: http status ", res.StatusCode)
+	}
+	defer res.Body.Close()
+
+	body, err := io.ReadAll(res.Body)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	if opmeteo.debug {
+		log.Println("Weather request:", requri)
+		b, _ := json.MarshalIndent(body, "", "\t")
+		fmt.Println("Weather response:", string(b))
+	}
+
+	var resp openmeteoResponse
+	if err = json.Unmarshal(body, &resp); err != nil {
+		log.Println(err)
+	}
+
+	ret.Current = parseCurCond(resp.Current)
+	ret.Location = location
+
+	forecast := opmeteo.parseDaily(resp.Hourly)
+
+	if len(forecast) > 0 {
+		forecast[0].Astronomy.Sunset = time.Unix(resp.Daily.Sunset[0], 0)
+		forecast[0].Astronomy.Sunrise = time.Unix(resp.Daily.Sunrise[0], 0)
+		ret.Forecast = forecast
+	}
+
+	return ret
+}
+
+func init() {
+	iface.AllBackends["openmeteo"] = &openmeteoConfig{}
+}