[Rerun Viewer] Save blueprint... doesn't open file dialog inside Docker container.

[Tuntenfisch]

Describe the bug
I have a VS Code Dev Container set up with Rerun. Everything works fine except for the fact that any action inside the Rerun viewer that normally opens a file dialog does nothing.

To Reproduce
Steps to reproduce the behavior:

1. Open an empty folder in VS Code
2. Create .devcontainer/devcontainer.json:

{
	"build": {
		"dockerfile": "dockerfile",
		"context": ".."
	},
	"initializeCommand": [".devcontainer/initialize_command"],
	"runArgs": ["--network=host", "--runtime=nvidia"]
}

3. Create .devcontainer/dockerfile:

FROM ubuntu:24.04

SHELL ["/bin/bash", "-c"]

RUN apt-get update && apt-get -y install --no-install-recommends \
    sudo

RUN echo ubuntu ALL=\(root\) NOPASSWD:ALL > /etc/sudoers.d/ubuntu && \
    chmod 0440 /etc/sudoers.d/ubuntu

USER ubuntu

RUN sudo apt-get update && sudo apt-get install -y --no-install-recommends \
        libclang-dev \
        libatk-bridge2.0 \
        libfontconfig1-dev \
        libfreetype6-dev \
        libglib2.0-dev \
        libgtk-3-dev \
        libssl-dev \
        libxcb-render0-dev \
        libxcb-shape0-dev \
        libxcb-xfixes0-dev \
        libxkbcommon-dev \
        patchelf \
        vulkan-tools \
        mesa-vulkan-drivers \
        libxkbcommon-x11-0

RUN sudo apt install -y --no-install-recommends \
        python3-dev \
        python3-pip && \
    pip install --break-system-packages \
        rerun-sdk

ENV NVIDIA_DRIVER_CAPABILITIES=all
ENV NVIDIA_VISIBLE_DEVICES=all

4. Create .devcontainer/initialize_command:

#!/usr/bin/env bash

setup_xhost_forwarding() {
  # Ensure docker can forward GUI applications.
  if [[ -x "$(command -v xhost)" ]]; then
    xhost +local:docker > /dev/null
  fi
}

setup_xhost_forwarding

5. Open the VS Code command palette and start the container via > Dev Containers: Reopen in Container
6. Inside the container, open a terminal and execute rerun
7. Inside the opened Rerun viewer, select an action from the top left menu such as "Save blueprint..." or "Open...".
8. Observe that nothing happens.

Expected behavior
When triggering an action inside the Rerun viewer that normally opens up a file dialog, e.g. "Save blueprint..." or "Open...", a file dialog should open up.

Actual behavior
No file dialog opens up. The action simply fails silently.

Desktop:
Output of lsb_release -a:

No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 22.04.4 LTS
Release:	22.04
Codename:	jammy

Rerun version

rerun-cli 0.16.1 [rustc 1.76.0 (07dca489a 2024-02-04), LLVM 17.0.6] x86_64-unknown-linux-gnu 6447/merge d24e449, built 2024-05-29T15:06:39Z

Additional context
Output inside the terminal when starting Rerun:

[2024-07-05T21:47:46Z INFO  re_sdk_comms::server] Hosting a SDK server over TCP at 0.0.0.0:9876. Connect with the Rerun logging SDK.
[2024-07-05T21:47:47Z INFO  winit::platform_impl::platform::x11::window] Guessed window scale factor: 1
error: XDG_RUNTIME_DIR is invalid or not set in the environment.
error: XDG_RUNTIME_DIR is invalid or not set in the environment.
error: XDG_RUNTIME_DIR is invalid or not set in the environment.
error: XDG_RUNTIME_DIR is invalid or not set in the environment.
[2024-07-05T21:47:47Z INFO  egui_wgpu] There were 2 available wgpu adapters: {backend: Vulkan, device_type: DiscreteGpu, name: "NVIDIA GeForce RTX 4070 Laptop GPU", driver: "NVIDIA", driver_info: "535.183.01", vendor: 0x10DE, device: 0x2820}, {backend: Vulkan, device_type: Cpu, name: "llvmpipe (LLVM 17.0.6, 256 bits)", driver: "llvmpipe", driver_info: "Mesa 24.0.5-1ubuntu1 (LLVM 17.0.6)", vendor: 0x10005}

[Tuntenfisch]

Okay, I'm not familiar at all with Rust but I compiled from source and found out that if I change the rfd dependency inside rerun-io/rerun/Cargo.toml to

rfd = { version = "0.12", default-features = false, features = ["gtk3"] }

a file dialog opens. So it seems to work if the backend is gtk3 and fails if the backend is xdg-portal. But I have no idea what to do with this information. Can I change something in my Docker container to make it work with xdg-portal?

[Tuntenfisch]

Okay, I've noticed that changing the rfd dependency to

rfd = { version = "0.14.1", default-features = false, features = ["async-std", "xdg-portal"] }

allows the file dialog to open just fine inside the container while still using xdg-portal as a backend. Not sure of the implications of bumping the rfd version, tho...

[emilk]

Bumping rfd sounds good to me! You wanna make a PR?

[Tuntenfisch]

Bumping rfd sounds good to me! You wanna make a PR?

Okay, will do. After some more testing I noticed that rfd version 0.14.1 works because of PolyMeilex/rfd@ad3cdef which added a zenity fallback for xdg-portal. So I additionally need to have zenity installed inside my Docker container (which I don't mind).