Where can I listen for the "onprogress" event?

[blackcater]

I want to implement a progress bar. So I need to listen "onprogress" event. But I can't find any about it in doc.

I use reqwest@2.0.5 as below.

    reqwest({
          url: methodPostApi().uploadFilesToQiniu,
          method: 'post',
          crossOrigin: true,
          processData : false,
          data: formData,
          progress: (event) => {
                console.log("on progress") // I can't find it in console
                console.dir(event)
          }
    })

Nothing happened !