気象庁APIからエリアコードを取得する

気象庁のエリアコードを取得と検索をするコード

interface AreaInfo {
  name: string;
  enName: string;
  officeName?: string;
  kana?: string;
  parent: string;
  children?: string[];
}

interface AreaCodeData {
  centers?: { [key: string]: AreaInfo };
  offices?: { [key: string]: AreaInfo };
  class10s?: { [key: string]: AreaInfo };
  class15s?: { [key: string]: AreaInfo };
  class20s?: { [key: string]: AreaInfo };
  [key: string]: any;
}

export async function getAreaCode(): Promise<AreaCodeData> {
  const AREA_CODE_JSON_URL = "https://www.jma.go.jp/bosai/common/const/area.json"
  const response = await fetch(AREA_CODE_JSON_URL);
  const json = await response.json();

  return json;
}

export async function searchByName(name: string): Promise<{ code: string; info: AreaInfo }[]> {
  const data = await getAreaCode();
  const results: { code: string; info: AreaInfo }[] = [];

  // centers, offices, class10s などすべてのカテゴリを検索
  for (const category of Object.values(data)) {
    if (typeof category === 'object' && category !== null) {
      for (const [code, info] of Object.entries(category)) {
        if (info && typeof info === 'object' && 'name' in info && info.name === name) {
          results.push({ code, info: info as AreaInfo });
        }
      }
    }
  }

  return results;
}

const data = await searchByName('東京都');
console.log(data);

東京都の結果

[
  {
    code: '130000',
    info: {
      name: '東京都',
      enName: 'Tokyo',
      officeName: '気象庁',
      parent: '010300',
      children: [Array]
    }
  }
]

府中市にすると以下のようになる

[
  {
    code: '1320600',
    info: {
      name: '府中市',
      enName: 'Fuchu City',
      kana: 'ふちゅうし',
      parent: '130013'
    }
  },
  {
    code: '3420800',
    info: {
      name: '府中市',
      enName: 'Fuchu City',
      kana: 'ふちゅうし',
      parent: '340012'
    }
  }
]