itd/weather.go

284 lines
6.9 KiB
Go

package main
import (
"context"
"encoding/json"
"fmt"
"math"
"net/http"
"net/url"
"strconv"
"strings"
"time"
"github.com/rs/zerolog/log"
"go.arsenm.dev/infinitime"
"go.arsenm.dev/infinitime/weather"
)
// METResponse represents a response from
// the MET Norway API
type METResponse struct {
Properties struct {
Timeseries []struct {
Time time.Time
Data METData
}
}
}
// METData represents data in a METResponse
type METData struct {
Instant struct {
Details struct {
AirPressure float32 `json:"air_pressure_at_sea_level"`
AirTemperature float32 `json:"air_temperature"`
DewPoint float32 `json:"dew_point_temperature"`
CloudAreaFraction float32 `json:"cloud_area_fraction"`
FogAreaFraction float32 `json:"fog_area_fraction"`
RelativeHumidity float32 `json:"relative_humidity"`
UVIndex float32 `json:"ultraviolet_index_clear_sky"`
WindDirection float32 `json:"wind_from_direction"`
WindSpeed float32 `json:"wind_speed"`
}
}
NextHour struct {
Summary struct {
SymbolCode string `json:"symbol_code"`
}
Details struct {
PrecipitationAmount float32 `json:"precipitation_amount"`
}
} `json:"next_1_hours"`
}
// OSMData represents lat/long data from
// OpenStreetMap Nominatim
type OSMData []struct {
Lat string `json:"lat"`
Lon string `json:"lon"`
}
var sendWeatherCh = make(chan struct{}, 1)
func initWeather(ctx context.Context, dev *infinitime.Device) error {
if !k.Bool("weather.enabled") {
return nil
}
// Get location based on string in config
lat, lon, err := getLocation(ctx, k.String("weather.location"))
if err != nil {
return err
}
timer := time.NewTimer(time.Hour)
go func() {
for {
// Attempt to get weather
data, err := getWeather(ctx, lat, lon)
if err != nil {
log.Warn().Err(err).Msg("Error getting weather data")
// Wait 15 minutes before retrying
time.Sleep(15 * time.Minute)
continue
}
// Get current data
current := data.Properties.Timeseries[0]
currentData := current.Data.Instant.Details
// Add temperature event
err = dev.AddWeatherEvent(weather.TemperatureEvent{
TimelineHeader: weather.NewHeader(
weather.EventTypeTemperature,
time.Hour,
),
Temperature: int16(round(currentData.AirTemperature * 100)),
DewPoint: int16(round(currentData.DewPoint)),
})
if err != nil {
log.Error().Err(err).Msg("Error adding temperature event")
}
// Add precipitation event
err = dev.AddWeatherEvent(weather.PrecipitationEvent{
TimelineHeader: weather.NewHeader(
weather.EventTypePrecipitation,
time.Hour,
),
Type: parseSymbol(current.Data.NextHour.Summary.SymbolCode),
Amount: uint8(round(current.Data.NextHour.Details.PrecipitationAmount)),
})
if err != nil {
log.Error().Err(err).Msg("Error adding precipitation event")
}
// Add wind event
err = dev.AddWeatherEvent(weather.WindEvent{
TimelineHeader: weather.NewHeader(
weather.EventTypeWind,
time.Hour,
),
SpeedMin: uint8(round(currentData.WindSpeed)),
SpeedMax: uint8(round(currentData.WindSpeed)),
DirectionMin: uint8(round(currentData.WindDirection)),
DirectionMax: uint8(round(currentData.WindDirection)),
})
if err != nil {
log.Error().Err(err).Msg("Error adding wind event")
}
// Add cloud event
err = dev.AddWeatherEvent(weather.CloudsEvent{
TimelineHeader: weather.NewHeader(
weather.EventTypeClouds,
time.Hour,
),
Amount: uint8(round(currentData.CloudAreaFraction)),
})
if err != nil {
log.Error().Err(err).Msg("Error adding clouds event")
}
// Add humidity event
err = dev.AddWeatherEvent(weather.HumidityEvent{
TimelineHeader: weather.NewHeader(
weather.EventTypeHumidity,
time.Hour,
),
Humidity: uint8(round(currentData.RelativeHumidity)),
})
if err != nil {
log.Error().Err(err).Msg("Error adding humidity event")
}
// Add pressure event
err = dev.AddWeatherEvent(weather.PressureEvent{
TimelineHeader: weather.NewHeader(
weather.EventTypePressure,
time.Hour,
),
Pressure: int16(round(currentData.AirPressure)),
})
if err != nil {
log.Error().Err(err).Msg("Error adding pressure event")
}
// Reset timer to 1 hour
timer.Stop()
timer.Reset(time.Hour)
// Wait for timer to fire or manual update signal
select {
case <-timer.C:
case <-sendWeatherCh:
}
}
}()
return nil
}
// getLocation returns the latitude and longitude
// given a location
func getLocation(ctx context.Context, loc string) (lat, lon float64, err error) {
// Create request URL and perform GET request
reqURL := fmt.Sprintf("https://nominatim.openstreetmap.org/search.php?q=%s&format=jsonv2", url.QueryEscape(loc))
req, err := http.NewRequestWithContext(ctx, http.MethodGet, reqURL, nil)
if err != nil {
return
}
res, err := http.DefaultClient.Do(req)
if err != nil {
return
}
// Decode JSON from response into OSMData
data := OSMData{}
err = json.NewDecoder(res.Body).Decode(&data)
if err != nil {
return
}
// If no data points
if len(data) == 0 {
return
}
// Get first data point
out := data[0]
// Attempt to parse latitude
lat, err = strconv.ParseFloat(out.Lat, 64)
if err != nil {
return
}
// Attempt to parse longitude
lon, err = strconv.ParseFloat(out.Lon, 64)
if err != nil {
return
}
return
}
// getWeather gets weather data given a latitude and longitude
func getWeather(ctx context.Context, lat, lon float64) (*METResponse, error) {
// Create new GET request
req, err := http.NewRequestWithContext(
ctx,
http.MethodGet,
fmt.Sprintf(
"https://api.met.no/weatherapi/locationforecast/2.0/complete?lat=%.2f&lon=%.2f",
lat,
lon,
),
nil,
)
if err != nil {
return nil, err
}
// Set identifying user agent as per NMI requirements
req.Header.Set("User-Agent", fmt.Sprintf("ITD/%s gitea.arsenm.dev/Arsen6331/itd", version))
// Perform request
res, err := http.DefaultClient.Do(req)
if err != nil {
return nil, err
}
// Decode JSON from response to METResponse struct
out := &METResponse{}
err = json.NewDecoder(res.Body).Decode(out)
if err != nil {
return nil, err
}
return out, nil
}
// parseSymbol determines what type of precipitation a symbol code
// codes for.
func parseSymbol(symCode string) weather.PrecipitationType {
switch {
case strings.Contains(symCode, "lightrain"):
return weather.PrecipitationTypeRain
case strings.Contains(symCode, "rain"):
return weather.PrecipitationTypeRain
case strings.Contains(symCode, "snow"):
return weather.PrecipitationTypeSnow
case strings.Contains(symCode, "sleet"):
return weather.PrecipitationTypeSleet
case strings.Contains(symCode, "snow"):
return weather.PrecipitationTypeSnow
default:
return weather.PrecipitationTypeNone
}
}
// round rounds 32-bit floats to 32-bit integers
func round(f float32) int32 {
return int32(math.Round(float64(f)))
}