How I can know audio/video duration before uploading?

Question

I need to upload file (audio/video) using default input type='file' and the I should pass duration of the video in api request, how i ca do this?

  const uploadFile = async (event) => {
    let file = await event.target.files[0];
    //here api POST request where i should pass duration
   }:

Answer 1

You can get the audio duration with HTMLMediaElement.duration:

async function getDuration(file) {
 const url = URL.createObjectURL(file);

 return new Promise((resolve) => {
   const audio = document.createElement("audio");
   audio.muted = true;
   const source = document.createElement("source");
   source.src = url; //--> blob URL
   audio.preload= "metadata";
   audio.appendChild(source);
   audio.onloadedmetadata = function(){
      resolve(audio.duration)
   };
 });
}

Then in your function:

const uploadFile = async (event) => {
   let file = event.target.files[0];
    //here api POST request where i should pass duration
   const duration = await getDuration(file);
 }: