package main import ( "context" "fmt" "io/ioutil" "log" "net/http" "strconv" pb "codeberg.org/andyscott/OpenWeather-gRPC-API/proto" "google.golang.org/grpc/codes" "google.golang.org/grpc/status" ) // Receives a gRPC request for the current forecast // Returns a SendCurrent message containing the forecast in JSON func (s *Server) Current(ctx context.Context, in *pb.RequestCurrent) (*pb.SendCurrent, error) { log.Printf("'Current' called: %v\n", in) token := "&appid=" + s.ApiKey url, err := s.createCurrentUrl(in) if err != nil { return nil, status.Errorf( codes.InvalidArgument, fmt.Sprintf("Invalid location or location type: %s, %s\n", in.Location.String(), in.LocationType.String()), ) } fcst, err := fetchForecast(url + token) if err != nil { return nil, status.Errorf( codes.Internal, fmt.Sprintf( "A server error occurred while fetching the forecast: %v\n", err, )) } return &pb.SendCurrent{ Payload: fcst, }, nil } // Assembles the URL for current weather requests to OpenWeather func (s *Server) createCurrentUrl(in *pb.RequestCurrent) (string, error) { url := "https://api.openweathermap.org/data/2.5/weather?" units := updateUnits(in.Units) lat, lon, err := s.fetchLocation(in.LocationType, in.Location) if err != nil { return "", err } url += fmt.Sprintf("lat=%f", lat) + fmt.Sprintf("&lon=%f", lon) + units return url, nil } // Creates the units portion of the request to OpenWeater func updateUnits(units pb.Units) string { unitStr := "&units=" switch units { case pb.Units_UNITS_IMPERIAL: unitStr += "imperial" case pb.Units_UNITS_METRIC: unitStr += "metric" default: unitStr += "standard" } return unitStr } // Obtains a locations exact coordinates for the request to OpenWeather func (s *Server) fetchLocation(locType pb.LocationType, loc *pb.OneOfLocation) (float32, float32, error) { var lat, lon float32 var err error switch locType { case pb.LocationType_LOCATION_TYPE_CITY: lat, lon, err = fetchCityCoords(loc.GetCity(), s.ApiKey) case pb.LocationType_LOCATION_TYPE_ZIP_CODE: lat, lon, err = fetchZipCoords(loc.GetZipCode(), s.ApiKey) case pb.LocationType_LOCATION_TYPE_COORDS: lat = loc.GetCoords().Latitude lon = loc.GetCoords().Longitude default: _, err = strconv.Atoi(loc.GetZipCode()) if err != nil { lat, lon, err = fetchCityCoords(loc.GetCity(), s.ApiKey) } else { lat, lon, err = fetchZipCoords(loc.GetZipCode(), s.ApiKey) } } if err != nil { return 0, 0, err } return lat, lon, nil } // Obtains forecasts from OpenWeather // Receives the URL as a string // Returns the JSON response from OpenWeather func fetchForecast(url string) (string, error) { res, err := http.Get(url) if err != nil { log.Printf("Error fetching forecast: %v\n", err) return "", err } defer res.Body.Close() body, err := ioutil.ReadAll(res.Body) if err != nil { log.Printf("Error reading response from OpenWeather: %v\n", err) return "", err } return string(body), nil }