如何使用适用于FIrebase的云函数在上传到firebase存储时获取mp3文件的持续时间

firebase login
firebase use --add

firebase init functions

const functions = require('firebase-functions');
const admin = require('firebase-admin');
const fs = require('fs');
const path = require('path');
const ffmpeg = require('fluent-ffmpeg');

admin.initializeApp();

exports.getMP3Duration = functions.storage.object().onFinalize(async (object) => {
  const filePath = object.name;
  const bucket = admin.storage().bucket(object.bucket);
  const tempFilePath = path.join(os.tmpdir(), filePath);

  await bucket.file(filePath).download({ destination: tempFilePath });

  const duration = await new Promise((resolve, reject) => {
    ffmpeg.ffprobe(tempFilePath, (err, metadata) => {
      if (err) {
        reject(err);
      } else {
        resolve(metadata.format.duration);
      }
    });
  });

  console.log('MP3 duration:', duration);

  // 可以根据需要将持续时间保存到数据库或进行其他操作

  return null;
});

npm install --save @google-cloud/storage ffmpeg fluent-ffmpeg

firebase deploy --only functions