Debugging with CLI

It is possible to do most things, including source-level debugging, profiling and hot reload when you debug Flutter apps for eLinux.

1. Getting the Observatory port

You will find the following message in the console when you run Flutter apps. You need to attach a debugger to this port when you want to debug it. Note that the URI changes every time after launching.

flutter: Observatory listening on http://127.0.0.1:43377/390I4oPyQ0U=/

Use fixed observatory URI

If you want to fix always same observatory URI, you can use the following command options. Note that this option is only available in debug/profile mode.

$ flutter-elinux run -d elinux-wayland --disable-service-auth-codes\
    --device-vmservice-port=12345 --host-vmservice-port=42771

(snip)

An Observatory debugger and profiler on eLinux is available at: http://127.0.0.1:42771/

2. Flutter attach debugger

$ cd <path_to_flutter_project>/
$ flutter-elinux attach --device-id=flutter-tester --debug-uri=http://127.0.0.1:43377/390I4oPyQ0U=/
Syncing files to device Flutter test device...                      8.5s

Flutter run key commands.
r Hot reload. 🔥🔥🔥
R Hot restart.
h List all available interactive commands.
d Detach (terminate "flutter run" but leave application running).
c Clear the screen
q Quit (terminate the application on the device).

💪 Running with sound null safety 💪

An Observatory debugger and profiler on Flutter test device is available at: http://127.0.0.1:43377/390I4oPyQ0U=/.,
The Flutter DevTools debugger and profiler on Flutter test device is available at:
http://127.0.0.1:9102?uri=http://127.0.0.1:43377/390I4oPyQ0U=/.,