Announcement & RFC: Pixbooster module

taophp · April 12, 2024, 3:57pm

Modern image file formats such as AVIF, JXL and WebP seem to be powerful, overcome previous formats and are recommended by search engines. But most CMS and related tools rarely support them. So I have the idea to provide such support at the Caddy level using an http handler module: Pixbooster

After a few days of work, I managed to create a first version which do not work too badly. As this is my first module for Caddy and my first project in Go, before going further, I would like to submit my work to your code review. All comments are welcome if kindly provided!

matt · April 12, 2024, 7:09pm

Very cool, thanks for sharing!

Might I suggest, instead of using httptest.NewRecorder:

github.com

PixyBlue/caddy-pixbooster/blob/6f6a8299983af35c5106d7a0bff3b91d75297bce/module.go#L112


      
          		w.Header().Set("Content-Type", format.mimeType)
          
          		if _, err := io.Copy(w, imgStream); err != nil {
          			p.logger.Error("Error sending image data: " + err.Error())
          			http.Error(w, "Internal server error", http.StatusInternalServerError)
          			return nil
          		}
          	}
          
          	if next != nil {
          		rec := httptest.NewRecorder()
          		err := next.ServeHTTP(rec, r)
          		if err != nil {
          			return err
          		}
          
          		contentType := rec.Header().Get("Content-Type")
          		if strings.HasPrefix(contentType, "text/html") {
          
          			body := rec.Body.Bytes()
          			doc, err := html.Parse(bytes.NewReader(body))

Use caddyhttp.ResponseRecorder:

https://pkg.go.dev/github.com/caddyserver/caddy/v2/modules/caddyhttp#NewResponseRecorder

This type is designed to be more efficient because it only buffers if necessary.

taophp · April 13, 2024, 1:45pm

Thanks for your comments, @matt, as kind as always. I will make the suggested change.
Another question: the WebP library I’m using requires CGO_ENABLED=1 to compile. Is this a problem for distributing the module through the Caddy download page? I tried to find a library that didn’t require this, but couldn’t find any, except for bindings that require external libraries installed on the host.

matt · April 13, 2024, 1:46pm

Yes, we don’t typically build C/cgo packages on our build server, so you’ll need to find another way to distribute that unfortunately.

taophp · April 13, 2024, 1:52pm

I thought so. It’s a shame that WebP encoding support is so poorly implemented in Go. I think I’ll drop it. AVIF and JXL alone should make the trick.

matt · April 13, 2024, 1:54pm

You might be able to make it optional behind a build flag that only includes it if cgo is enabled.

// +build cgo

taophp · April 13, 2024, 2:07pm

Thanks for the tip ! I’ll try it next monday !

taophp · April 15, 2024, 4:09pm

Done !