I tried to make a pdf viewer it is working fine on desktop. But when I try to run it on the web, I get the following error

[saurabhwadekar]

Question

I tried to make a pdf viewer it is working fine on desktop.
But when I try to run it on the web, I get the following error

Code sample

import flet as ft
from pdf2image import convert_from_path
import base64
import threading
from io import BytesIO


class PdfViewer(ft.UserControl):
    def __init__(
        self,
        pdf_path: str,
        ref: ft.Ref | None = None,
        heigth = None,
        width = None,
        scroll = None,
        on_cut  = None,
    ):
        super().__init__(ref=ref)
        self.pdf_path = pdf_path
        self.pdf_height = heigth
        self.pdf_width = width
        self.on_cut = on_cut
        self.pdf_scroll = scroll
        self.pages = [
             ft.Row(
                [
                    ft.Container(height=30),
                ],
                alignment=ft.MainAxisAlignment.SPACE_AROUND,
            ),
            ft.Row(
                [ft.ProgressRing(),],
                alignment=ft.MainAxisAlignment.SPACE_AROUND,
            ),
        ]
        t = threading.Thread(target=self.return_base64_images)
        t.start()

        self.main_stack = ft.Stack(
            controls=[
                ft.Column(
                    scroll=self.pdf_scroll,
                    controls=self.pages,
                    expand=True
                ),
                ft.IconButton(
                    icon=ft.icons.CANCEL,
                    on_click=self.on_cut
                ),
            ],
            height=self.pdf_height,
            width=self.pdf_width,
        )
        
    def build(self):
        return self.main_stack

    def return_base64_images(self):
        images = convert_from_path(self.pdf_path)
        self.pages.clear()
        for img in range(len(images)):
            buffered = BytesIO()
            images[img].save(buffered, format="png")
            img_base64_str = base64.b64encode(buffered.getvalue()).decode()
            self.pages.append(
                ft.Image(
                    src_base64=img_base64_str,
                )
            )
            del img_base64_str
            del buffered
            del img

        del images
        self.update()

Error message

╭─saurabh@saurabh in repo: sscc/sscc_student_app on  main [!] via  v3.10.9 (venv) took 18s
╰─λ flet run main.py --web
http://127.0.0.1:36265
Opening in existing browser session.
MESA-INTEL: warning: Haswell Vulkan support is incomplete
libva error: /usr/lib/dri/iHD_drv_video.so init failed
Exception in thread Thread-24 (return_base64_images):
Traceback (most recent call last):
File "/usr/lib/python3.10/threading.py", line 1016, in _bootstrap_inner
self.run()
File "/usr/lib/python3.10/threading.py", line 953, in run
self._target(*self._args, **self._kwargs)
File "/home/saurabh/Desktop/sscc/sscc_student_app/components/pdf_viewer.py", line 75, in return_base64_images
self.update()
File "/home/saurabh/Desktop/sscc/sscc_student_app/venv/lib/python3.10/site-packages/flet_core/control.py", line 261, in update
self.__page.update(self)
File "/home/saurabh/Desktop/sscc/sscc_student_app/venv/lib/python3.10/site-packages/flet_core/page.py", line258, in update
r = self.__update(*controls)
File "/home/saurabh/Desktop/sscc/sscc_student_app/venv/lib/python3.10/site-packages/flet_core/page.py", line362, in __update
results = self.__conn.send_commands(self._session_id, commands).results
File "/home/saurabh/Desktop/sscc/sscc_student_app/venv/lib/python3.10/site-packages/flet/sync_websocket_connection.py", line 130, in send_commands
response = self._send_message_with_result(
File "/home/saurabh/Desktop/sscc/sscc_student_app/venv/lib/python3.10/site-packages/flet/sync_websocket_connection.py", line 145, in _send_message_with_result
self.__ws.send(j)
File "/home/saurabh/Desktop/sscc/sscc_student_app/venv/lib/python3.10/site-packages/flet/reconnecting_websocket.py", line 51, in send
self.wsapp.send(message)
File "/home/saurabh/Desktop/sscc/sscc_student_app/venv/lib/python3.10/site-packages/websocket/_app.py", line239, in send
if not self.sock or self.sock.send(data, opcode) == 0:
File "/home/saurabh/Desktop/sscc/sscc_student_app/venv/lib/python3.10/site-packages/websocket/_core.py", line 283, in send
return self.send_frame(frame)
File "/home/saurabh/Desktop/sscc/sscc_student_app/venv/lib/python3.10/site-packages/websocket/_core.py", line 311, in send_frame
l = self._send(data)
File "/home/saurabh/Desktop/sscc/sscc_student_app/venv/lib/python3.10/site-packages/websocket/_core.py", line 525, in _send
return send(self.sock, data)
File "/home/saurabh/Desktop/sscc/sscc_student_app/venv/lib/python3.10/site-packages/websocket/_socket.py", line 170, in send
return _send()
File "/home/saurabh/Desktop/sscc/sscc_student_app/venv/lib/python3.10/site-packages/websocket/_socket.py", line 147, in _send
return sock.send(data)
ConnectionResetError: [Errno 104] Connection reset by peer

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• I have searched for answers to my question both in the issues and in previous discussions.

[ipritom]

I'm facing the similar issue while working with OpenCV. Did you solve it?

[saurabhwadekar]

No . But I think it will be solved in the upcoming updates.