force download image as response lumen + intervention image - php

Question

I'm using intervention image on my Lumen project and everything works until I come across on making the encoded image as a downloadable response which upon form submit that contains the image file that will be formatted unto specific format e.g. webp, jpg, png will be sent back as a downloadable file to the user, below is my attempt.
public function image_format(Request $request){
$this->validate($request, [
'image' => 'required|file',
]);
$raw_img = $request->file('image');
$q = (int)$request->input('quality',100);
$f = $request->input('format','jpg');
$img = Image::make($raw_img->getRealPath())->encode('webp',$q);
header('Content-Type: image/webp');
echo $img;
}
but unfortunately, its not my expected output, it just did display the image.
from this post, I use the code and attempt to achieve my objective
public function image_format(Request $request){
$this->validate($request, [
'image' => 'required|file',
]);
$raw_img = $request->file('image');
$q = (int)$request->input('quality',100);
$f = $request->input('format','jpg');
$img = Image::make($raw_img->getRealPath())->encode('webp',$q);
$headers = [
'Content-Type' => 'image/webp',
'Content-Disposition' => 'attachment; filename='. $raw_img->getClientOriginalName().'.webp',
];
$response = new BinaryFileResponse($img, 200 , $headers);
return $response;
}
but its not working, instead it showed me this error
any help, ideas please?

Answer 1

In Laravel you could use the response()->stream(), however, as mentioned in the comments, Lumen doesn't have a stream method on the response. That being said the stream() method is pretty much just a wrapper to return a new instance of StreamedResponse (which should already be included in your dependencies).
Therefore, something like the following should work for you:
$raw_img = $request->file('image');
$q = (int)$request->input('quality', 100);
$f = $request->input('format', 'jpg');
$img = Image::make($raw_img->getRealPath())->encode($f, $q);
return new \Symfony\Component\HttpFoundation\StreamedResponse(function () use ($img) {
echo $img;
}, 200, [
'Content-Type' => 'image/jpeg',
'Content-Disposition' => 'attachment; filename=' . 'image.' . $f,
]);