weather.js

const weather = document.querySelector(".js-weather");
const API_KEY = "9f42a8c72c12611107970f3fa2ede3ef";
const COORDS = "coords";

function getWeather(lat, lng) {
  fetch(
    `http://api.openweathermap.org/data/2.5/weather?lat=${lat}&lon=${lng}&appid=${API_KEY}&units=metric`
  )
    .then(function (response) {
      //fetch로 전달받은 데이터 인자로 들어감
      return response.json(); // json으로 형식 변환
    })
    .then(function (json) {
      const temperature = json.main.temp;
      const place = json.name;
      weather.innerHTML = `${temperature} @ ${place}`;
    });
}

function saveCoords(coordsObj) {
  localStorage.setItem(COORDS, JSON.stringify(coordsObj));
}

function handleGeoSucces(position) {
  const latitude = position.coords.latitude;
  const longitude = position.coords.longitude;
  const coordsObj = {
    latitude,
    longitude,
  };
  saveCoords(coordsObj);
  getWeather(latitude, longitude);
}
function handleGeoError() {
  console.log(position);
}

function askForCoords() {
  navigator.geolocation.getCurrentPosition(handleGeoSucces, handleGeoError); //위치 정보 요청 (Weather API)
}
function loadCoords() {
  const loadedCoords = localStorage.getItem(COORDS);
  if (loadedCoords === null) {
    askForCoords();
  } else {
    const parseCoords = JSON.parse(loadedCoords);
    getWeather(parseCoords.latitude, parseCoords.longitude);
  }
}

function init() {
  loadCoords();
}

init();