Connection interrupted when run "indirectly". Bottle.py on Ubuntu - python

I'm running a local web service on Ubuntu on localhost:8090, written with bottle.py.
The connection uses SSL.
If I execute the main.py file from Nautilus or the terminal and connect to https://localhost:8090 everything works fine.
When I execute it from a link to the file, an .sh script or a .desktop file the server starts running fine, but when I browse to the address firefox says "The connection to localhost:8090 was interrupted while the page was loading"
$telnet 127.0.0.1 8090 gives this:
Trying 127.0.0.1...
Connected to 127.0.0.1...
Escape character is '^]'.
Connection closed by foreign host.
$sudo netstat -ntlupp | grep 8090 gives this:
tcp 0 0 127.0.0.1:8090 0.0.0.0:* LISTEN
iptables is default
I've got the feeling it's blocking the connection when the server is executed "indirectly" (link, script or .desktop), since when I actually click on the file or run it through terminal it runs fine.
I don't have a clue on where to prevent it from blocking the connection, though. Any help is greatly appreciated.
Any workaround will do, even just pretending the file is being run directly from the user.
Thanks in advance

Watch the server logs.
The major difference between the different methods of invocation probably is the current working directory.
I think that it is unlikely that the network configuration is involved in what you are observing.
Depending on the complexity of your web application it might be that a Python import fails if the main script is not run from the right directory. This would trigger a Python exception, which might lead to an immediate connection reset. I have not worked with bottle, but other Python web frameworks distinguish a development mode in which Python tracebacks are shown in the browser, and a production mode in which an HTTP error is sent to the client.
This is what you should do in order to debug your issue: run your server from a terminal (cd to the right directory, then run python application.py). Carefully watch stdout and stderr of that server process while connecting to the web application with your browser.

Ok, problem solved.
It was actually depending on the current working directory not being the same as the python file running the WSGI server.
If I run the .sh script or the link from the same directory everything works fine, and if I give a cd command in the script everything works smoothly.
Thanks for the help Jan-Philip!

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