node.js - Problem with request's pipe method

Question

 request(src).pipe(fs.createWriteStream('./img/'+img_filename));

How to know that the picture has been written successfully? Instead of connecting successfully?

Answer 1

var writeStream = fs.createWriteStream('./img/'+img_filename);
request(src).pipe(writeStream);
readStream.on('end', function() { // 当没有数据时，关闭数据流
    writeStream.end();
});

Answer 2

Listen to the event of fs.createWriteStream