ナウキャストの画像取得(20240307版) by puppeteer/node.js

jmacapt.js

const puppeteer = require('puppeteer');
const fs = require('fs');
require('date-utils');
const { WebClient } = require('@slack/web-api');
const setTimeout = require("node:timers/promises").setTimeout;

async function selectorClicker(page, selector) {
  await page.waitForSelector(selector);
  const elementHandleList = await page.$$(selector);
  await elementHandleList[0].click();
  await setTimeout(1000);
}

const isExists = filePath =>{
    try{
        const data = fs.statSync(filePath);
        return data;
    }catch(e){
        return false;
    }
}

async function slack_notify(msg) {
  const token  = 'your token';
  // #チャンネル名 of @ユーザー名
  const channel = '#somewhere';
  const username = 'username';
  // メッセージ
  const client = new WebClient(token);
  const params = {
    channel: channel,
    text: msg,
    username: username
  };

  const response = await client.chat.postMessage(params);
  console.log(response);
}

(async () => {
  const now = new Date();
  let dateTemp = new Date();
  dateTemp.setHours(now.getHours()-1);
  const saveTimeOntheClock = new Date(dateTemp.getFullYear(), dateTemp.getMonth(), dateTemp.getDate(), dateTemp.getHours());

  // ブラウザ表示域のサイズで画像サイズが決まる
  const browser = await puppeteer.launch({headless: true, 'defaultViewport' : { 'width' : 1048, 'height' : 1000 }});

  console.log(saveTimeOntheClock.toFormat('YYYY/MM/DD HH24:MI:SS'));

  try{
    let loop_count = 0
    const page = await browser.newPage();
    const cdpSession = await page.target().createCDPSession();

    await cdpSession.send("Browser.setDownloadBehavior", {
      behavior : 'allow',
      downloadPath: fs.realpathSync('./')
    });

    await page.goto('https://www.jma.go.jp/bosai/nowc/#zoom:N/lat:AAA.AAAAAA/lon:OOO.OOOOOO/colordepth:normal/elements:hrpns', {waitUntil: "domcontentloaded"});
    //await page.screenshot({path: 'jma000.png'});

    // 最新時刻への更新
    {
      const selector = 'button[id^="jmatile_refresh_"]';
      await selectorClicker(page, selector);
    }
    //await page.screenshot({path: 'jma001.png'});

    // セーブしたい時刻(X時55分)への移動
    while (loop_count < 60) {
      const selector = 'div[class="noUi-tooltip"]';
      await page.waitForSelector(selector);
      const elementHandleList = await page.$$(selector);
      let value = await (await elementHandleList[0].getProperty('textContent')).jsonValue();
      console.log(value);
      let clock = value.split(':');
      let hour = saveTimeOntheClock.getHours();

      //await page.screenshot({path: 'jma002_' + clock[0] + clock[1] + '.png'});

      if (clock[0] == hour && clock[1] == '55') {
        loop_count = 0;
        break;
      }
      // 5分過去へ
      loop_count++;
      {
        const selector = 'button[id^="jmatile_time_prev_"]';
        await selectorClicker(page, selector);
      }
    }

    if (loop_count > 0) {
        throw 'Give up!';
    }

    // X時(5*i)分の画像取得 リカバリ分を含めて120分
    for(let i=0; i<120/5; i++){
      let clock = [];
      {
        const selector = 'div[class="noUi-tooltip"]';
        await page.waitForSelector(selector);
        const elementHandleList = await page.$$(selector);
        const value = await (await elementHandleList[0].getProperty('textContent')).jsonValue();
        console.log(value);
        clock = value.split(':');
      }
      // 保存先を決める
      const srcDate = new Date(dateTemp.getFullYear(), dateTemp.getMonth(), dateTemp.getDate(), clock[0], clock[1]);
      const srcDateUTC = srcDate.toUTCFormat('YYYYMMDDHH24MISS');
      const srcfile = fs.realpathSync('./') + '/' + 'nowc_hrpns_' + srcDateUTC + '_' + srcDateUTC + '.png';

      const dstdir = fs.realpathSync('./') + '/' + saveTimeOntheClock.toFormat('YYYY/MM/DD');
      const dstfile = dstdir + '/' + saveTimeOntheClock.toFormat('YYYYMMDD') + '_' + clock[0] + clock[1] + '.png';

      fs.mkdirSync(dstdir, { recursive: true });

      if (isExists(dstfile) == false){
          // メニュー出し
          {
            const selector = 'div[class="area-toggle"]';
            await selectorClicker(page, selector);
          }
          // 画像保存
          {
            const selector = 'div[class="area-download"]';
            await selectorClicker(page, selector);
          }

          let retry = 0;
          while (isExists(srcfile) == false && retry < 10) {
            await setTimeout(1000); // sure to be created
            retry++;
          }

          if (isExists(srcfile) == false){
              console.log(srcfile + ' not found.');
          }
          else{
              console.log(srcfile);
              fs.renameSync(srcfile, dstfile);
          }
      }
      
      // 5分過去へ
      {
        const selector = 'button[id^="jmatile_time_prev_"]';
        await selectorClicker(page, selector);
      }
      //await page.screenshot({path: 'jma003_' + clock[0] + clock[1] + '.png'});
    }
  } catch(e) {
    console.log(e.message);
    slack_notify('jmacapt.js: Error. check log.')
  } finally {
    await browser.close();
  }

})();

久しぶりにOSを更新したついでに
Chrome DevTools Protocol
というものでダウンロード先を指定するようにした。

waitForXPathやwaitForTimeoutが使えなくなるため、代替手段に切替え。