Hanging chromium processes

[makarychev13]

Version
Gotenberg 7.5.3
go 1.18.3

Description of the problem
Child chromium processes keep running after pdf conversion. And these processes die only after restarting the application. This problem was "fixed" in this PR.

There is a similar open issue in chromedp.

Code example

package main

import (
	"bytes"
	"context"
	"io"
	"mime/multipart"
	"net/http"
	"os"
)

func main() {
	var buf bytes.Buffer

	//read html from disk
	html, err := os.ReadFile("index.html")
	if err != nil {
		panic(err)
	}

	//prepare http request
	w := multipart.NewWriter(&buf)

	fw, _ := w.CreateFormFile("files", "index.html")
	if _, err := io.Copy(fw, bytes.NewReader(html)); err != nil {
		panic(err)
	}

	if err = w.Close(); err != nil {
		panic(err)
	}

	req, err := http.NewRequestWithContext(context.Background(), http.MethodPost, "http://127.0.0.1:3000/forms/chromium/convert/html", &buf)
	if err != nil {
		panic(err)
	}
        req.Header.Set("Content-Type", w.FormDataContentType())

	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		panic(err)
	}

	//save pdf to disk
	var pdf bytes.Buffer
	if _, err = io.Copy(&pdf, resp.Body); err != nil {
		panic(err)
	}

	if err := os.WriteFile("index.pdf", pdf.Bytes(), 0666); err != nil {
		panic(err)
	}
}

Effects

[gulien]

Hello @makarychev13,

It was indeed resolved in versions 6.x.x, where I was handling the Chrome process myself. In versions 7.x.x, I let chromedp do the heavy lifting.

That being said, I have no idea why it happens in our case:

• chromedp waits for the child process.
• I use tini to reap zombies, if any:

All Tini does is spawn a single child (Tini is meant to be run in a container), and wait for it to exit all the while reaping zombies and performing signal forwarding.

Also, on the demo instance, there is 0 zombie process 🤔 (it has been up for 124 consecutive days)

[ismurov]

Hi, @gulien. 👋

We found the problem. We just redefine ENTRYPOINT of Docker container while using in K8S by command property instead using arguments. And Tini was not used in our pods. Ha-Ha!

We apologize for the trouble.

[gulien]

Hello @ismurov,

Thanks for the heads up! I'll update the documentation so that one could avoid this mistake 😄