address already in use

[anizeani]

I watched the "Best Practices for Compose-managed Python Apps", thx for that! super informative and helpful.

I then tried to follow the same steps to debug the
project I'm working on: https://github.com/encointer/polkascan-os
My goal is to debug the explorer-api, which is a falcon (python) app.

So I:

1. added the port 5678 in the docker-compose file.
2. added the entry ptvsd==4.3.2 in the requirements.txt file
3. added the code snipped ptvsd.enable_attach(address=('0.0.0.0',5678)) // why 0.0.0.0 here?
4. docker-compose build and than docker-compose up
5. in vscode, I added the configuration file with "localRoot": "${workspaceFolder}/explorer-api/app" and
   "remoteRoot": "/usr/src/app/app/" // here I add the folder that points to main.py, is this correct?

The error I'm getting is: OSError: [Errno 98] Address already in use

I struggle to understand, where the problem is, I guess somehow this port is already in use, but if i change the port, the same error appears which leads me to think, that somehow the debugger or so creates 2 instances that try to connect to that port.

I'm not sure this is the correct place to file the issue, if somebody knows a solution or a better place to get answers to my question, I'd be very thankful.

Here is the error message trace log (i get it 3x):

ptvsd.enable_attach(address=('0.0.0.0',5678))

File "/usr/local/lib/python3.8/site-packages/ptvsd/attach_server.py", line 101, in enable_attach
ptvsd_enable_attach(address)
File "/usr/local/lib/python3.8/site-packages/ptvsd/_remote.py", line 76, in enable_attach
pydevd.settrace(host=host,
File "/usr/local/lib/python3.8/site-packages/ptvsd/_vendored/pydevd/pydevd.py", line 2169, in settrace
_locked_settrace(
File "/usr/local/lib/python3.8/site-packages/ptvsd/_vendored/pydevd/pydevd.py", line 2230, in _locked_settrace
debugger.connect(host, port) # Note: connect can raise error.
File "/usr/local/lib/python3.8/site-packages/ptvsd/_vendored/pydevd/pydevd.py", line 1060, in connect
s = start_client(host, port)
File "/usr/local/lib/python3.8/site-packages/ptvsd/pydevd_hooks.py", line 136, in _start_client
return start_client(daemon, h, p)
File "/usr/local/lib/python3.8/site-packages/ptvsd/_remote.py", line 62, in
start_client=(lambda daemon, h, port: start_daemon()),
File "/usr/local/lib/python3.8/site-packages/ptvsd/_remote.py", line 50, in start_daemon
_, next_session = daemon.start_server(addr=(host, port))
File "/usr/local/lib/python3.8/site-packages/ptvsd/daemon.py", line 161, in start_server
self._server = create_server(addr.host, addr.port)
File "/usr/local/lib/python3.8/site-packages/ptvsd/socket.py", line 79, in create_server
server.bind((host, port))
OSError: [Errno 98] Address already in use