AEMET Go Library

A Go library for retrieving weather data from the Spanish Meteorological Agency (AEMET) API.

Features

• Get weather station information
• Retrieve weather forecasts by municipality ID or name
• Built-in municipality search functionality
• Simple, lightweight client for accessing AEMET weather data
• Configurable via direct options or environment variables
• Returns structured Go objects for easy integration

Installation

go get -u github.com/rubiojr/aemet-go

Getting Started

API Key

You need an AEMET API key to use this library. You can obtain one from the AEMET OpenData website.

Set your API key as an environment variable:

export AEMET_API_KEY="your-api-key-here"

Or provide it directly in the configuration.

Usage

Basic Setup

package main

import (
    "fmt"
    "log"

    "github.com/rubiojr/aemet-go"
)

func main() {
    // Using environment variable AEMET_API_KEY
    client, err := aemet.NewWithDefaults()
    if err != nil {
        log.Fatal(err)
    }

    // Or configure directly
    client, err = aemet.New(aemet.Config{
        AemetApiKey: "your-api-key-here",
    })
    if err != nil {
        log.Fatal(err)
    }
}

Get Weather Stations

stations, err := client.GetStations()
if err != nil {
    log.Fatal(err)
}

for _, station := range stations {
    fmt.Printf("Station: %s (%s)\n", station.Name, station.ID)
    fmt.Printf("Location: %s, %s\n", station.Latitude, station.Longitude)
    fmt.Printf("Province: %s\n", station.Province)
    fmt.Println()
}

Get Weather Forecast by Municipality ID

// Get forecast for Madrid (municipality ID: 28079)
forecast, err := client.GetForecastFor("28079")
if err != nil {
    log.Fatal(err)
}

fmt.Printf("Forecast for %s, %s\n", forecast.Nombre, forecast.Provincia)
fmt.Printf("Updated: %s\n", forecast.Elaborado)

for _, day := range forecast.Prediccion.Dia {
    fmt.Printf("Date: %s\n", day.Fecha)
    fmt.Printf("Max Temperature: %d°C\n", day.Temperatura.Maxima)
    fmt.Printf("Min Temperature: %d°C\n", day.Temperatura.Minima)

    if len(day.EstadoCielo) > 0 {
        fmt.Printf("Sky: %s\n", day.EstadoCielo[0].Descripcion)
    }

    if len(day.ProbPrecipitacion) > 0 {
        fmt.Printf("Precipitation Probability: %d%%\n", day.ProbPrecipitacion[0].Value)
    }

    fmt.Println()
}

Get Weather Forecast by Municipality Name

// Get forecast by municipality name
forecast, err := client.GetForecastByName("Madrid")
if err != nil {
    log.Fatal(err)
}

fmt.Printf("Forecast for %s\n", forecast.Nombre)

Find Municipality Information

// Find municipality ID by exact name
id, err := aemet.FindMunicipalityID("Madrid")
if err != nil {
    log.Fatal(err)
}
fmt.Printf("Madrid ID: %s\n", id)

// Search municipalities by partial name
municipalities, err := aemet.FindMunicipalitiesByPartialName("Barce")
if err != nil {
    log.Fatal(err)
}

for _, muni := range municipalities {
    fmt.Printf("%s (ID: %s)\n", muni.Name, muni.ID)
}

// Get municipality info by ID
info, err := aemet.GetMunicipalityByID("08019")
if err != nil {
    log.Fatal(err)
}
fmt.Printf("Municipality: %s\n", info.Name)
fmt.Printf("Population: %s\n", info.NumHab)
fmt.Printf("Coordinates: %s, %s\n", info.LatitudeDec, info.LongitudeDec)

Configuration Options

The Config struct supports the following options:

type Config struct {
    AemetApiKey             string        // AEMET API key
    AemetWeatherStationCode string        // Weather station code (currently unused)
    HTTPClient              *http.Client  // Custom HTTP client
    Logger                  *log.Logger   // Custom logger
}

Environment Variables

• AEMET_API_KEY - Your AEMET API key

Data Structures

WeatherStation

type WeatherStation struct {
    Latitude  string `json:"latitud"`
    Province  string `json:"provincia"`
    Altitude  string `json:"altitud"`
    ID        string `json:"indicativo"`
    Name      string `json:"nombre"`
    IndSinop  string `json:"indsinop"`
    Longitude string `json:"longitud"`
}

Municipality Forecast

The Municipality struct contains detailed forecast information including:

• Nombre - Municipality name
• Provincia - Province name
• Prediccion - Forecast data with daily predictions
• Each day includes:
  • Temperature (max/min/hourly)
  • Precipitation probability
  • Sky conditions
  • Wind information
  • Relative humidity
  • UV index

MunicipalityInfo

type MunicipalityInfo struct {
    Name         string `json:"nombre"`
    ID           string `json:"id"`
    Capital      string `json:"capital"`
    NumHab       string `json:"num_hab"`
    Altitude     string `json:"altitud"`
    LatitudeDec  string `json:"latitud_dec"`
    LongitudeDec string `json:"longitud_dec"`
    // ... other fields
}

Error Handling

All methods return descriptive errors. Common error scenarios:

• Missing or invalid API key
• Municipality not found
• Network connectivity issues
• API rate limiting

License

MIT