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Error with Python subprocess when running Flask app using nginx + WSGI

I have developed a Python web server using Flask, and some of the endpoints make use of the subprocess module to call different executables. On development, using the Flask debug server, everything works fine. However, when running the server along with nginx+WSGI (on the exact same machine), some subprocess calls fail.
For example, one of the tools I'm using is Microsoft's dotnet, which I installed from my user as sudo apt-get install -y aspnetcore-runtime-5.0 and is then called from Python with the subprocess module. When I run the server with python3 server.py, it works like a charm. However, when using nginx and WSGI, the subprocess call fails with an exception that says: /bin/sh: 1: dotnet: not found.
I suspect this is due to the command not being accessible to the user and group running the server. I have used this guide as a reference to deploy the app, and on the wsgi .ini file, I have set uid = javierd and gid = www-data, while on the systemd .service file I have User=javierd, Group=www-data.
I have tried to add the executables' paths to /etc/profile, but it didn't work, and I don't know any other way to fix it. I find also very surprising that this happens to some executables, but not to all, and that it happes to dotnet, for example, which is located at /usr/bin/dotnet and therefore should be accessible to every user. Any idea on how to solve this problem? Furthermore, if somebody could explain me why this is happening, I would really appreciate the effort.
Thanks a lot!

Ok, finally after having a big headache, I noticed the error, and it was really simple.
On the tutorial I linked, when creating the system service file, the following line was included: Environment="PATH=/home/myuser/myfolder/enviroment/bin".
Of course, as this was overriding the path, there was no way of executing the commands. Once I notices it I just removed that line, restarted the service, and it was fixed.

Pycharm CE not hitting breakpoints in my Django project

I have my project properly configured to run manage.py in the right place, with the right settings.
I also have debug breakpoints set in a method that I know with certainty is being executed (I've put a print statement there and it executed as expected). The breakpoints are not disabled or conditional:
When I hit the "Run in debug mode" button, using the above run configuration (I'm sure it's the same one because it's the only one I've configured for this project), this is the console output I get:
pydev debugger: process 38083 is connecting
Connected to pydev debugger (build 192.5728.105)
Watching for file changes with StatReloader
Performing system checks...
System check identified no issues (0 silenced).
December 23, 2020 - 19:22:22
Django version 3.1.4, using settings 'FEArena.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.
When I tried putting a breakpoint in manage.py, it worked as expected, triggering just when I hit the 'debug' button. However, after the app has started, when I use a REST client to trigger the above method, the one with breakpoints in it, the breakpoints do not trigger and the debugger doesn't start. I get a 200 OK response in my REST client, but PyCharm does not stop and execute the debugger at any point.
I looked at other answers that advised setting "Gevent compatible debugging" (which I don't have, because I'm using Community Edition), and I've tried deleting the .idea/ folder for the project, which also didn't fix the issue. I'm not sure what else could be causing this. I just want to debug my program.
My PyCharm version information is
PyCharm 2019.2 (Community Edition)
Build #PC-192.5728.105, built on July 23, 2019
Runtime version: 11.0.3+12-b304.10 x86_64
VM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
macOS 10.15.7
GC: ParNew, ConcurrentMarkSweep
Memory: 4029M
Cores: 8
Registry:
Non-Bundled Plugins: com.karateca.jstoolbox, mobi.hsz.idea.latex, net.seesharpsoft.intellij.plugins.csv, nl.rubensten.texifyidea, org.intellij.plugins.markdown
What could be causing the breakpoints to not be triggered, and how do I fix this? I need breakpoints to debug other parts of my program.

Are you running your server in a console by any chance? If thats the case try stopping the server runing in console and restart the one in PyCharm

I was having a similar issue previously in PyCharm when I was invoking executor.submit. I had to insert a line requesting the results of the code in order to re-invoke the expected debugging behaviour. If your code is threaded, you may wish to start there.
future = executor.submit(control, channel) # spawn a function control(channel)
print(f'Future result is: {future.result()}') # new line I had to add to enable debugging
Edit: Adding the link to the thread that helped me with similar behaviour in PyCharm. concurrent.futures.ThreadPoolExecutor doesn't print errors

My current working configuration is on this :
It does not have any script path or parameters.
When I click on the "Debug" green button, the command automatically launched is :
/Users/.../virtualenv/bin/python /Applications/PyCharm.app/Contents/plugins/python/helpers/pydev/pydevd.py --multiproc --qt-support=auto --client 127.0.0.1 --port 55583 --file /Users/.../manage.py runserver 8000
What about yours ?

Hi I am writing this answer as I cannot comment because of my reputation no. By any chance, did you installed cython debugger toolkit that pycharm keeps on suggesting? If so, i have faced the same issue. The solution is to delete cython speedups somehow. You can follow this link to do that.
Basically you have to go to the directory called _pydevd_bundle and delete pydev*.so files. Now that requires root privilege. If you have that and you are able to delete them, then most likely it will work(provided you had installed cython debugger extension).

using flask in spyder stuck in local server

I am trying to create a web application using flask. I have already gotten somewhat comfortable with using python, and have done so using spyder, inside of Anacanda Navigator. Now I am playing around with flask doing basic functions and have successful so far by testing it out in local server 127.0.0.1:5000. The problem I am having is that I cannot stop the server once I run the script in spyder. I have stopped the script and run other scripts through the console, but the local server remains the same.
The reason this is a problem for me is because when I try to change files and run a different flask script, the server does not update with the new information. For example, if I run a flask script that returns "Hello World" on the main page, and then I stop that file, open a new file that has a different flask script that returns "The sky is blue" the server does not change when I check it on chrome or any other browser. It will onyl return "Hello World"
I have been able to fix this problem by completely restarting my computer, but I am wondering if there is another way, just to restart the local server, 127.0.0.1:5000. Thank You!
Also I am using windows

I do : "Run > Configuration per file > Execute in an external system terminal",
then when you run your .py containing the app.run, it will be launched in an external console. If you close the console the server will be closed too.

To Kill the local server, you may use Ctrl+C command and not any other command. This command is also mentioned when the server is up and running.

I've been having this precise issue and have been smashing my head against the wall for a couple of hours. I posted the referenced StackOverflow question (my first actually) and it seems that running a script from inside Spyder is the wrong way to go as it leaves runaway background processes running, even after restarting Spyder.
I got the recommendation to only launch my *.py code from the command prompt. Furthermore I was told to do this:
set FLASK_APP=main1.py then set FLASK_DEBUG=1 then flask run
though I'm not sure what that does, so I will investigate. I was about to restart my computer as a last ditch effort until I looked in my Windows Task Manager and found some Python tasks running. After [end task] them both I was able to launch the updated webpage on my local host.

django devserver can't connect

I have a situation where if I run Apache with wsgi (now uninstalled), a test website works, but running the same server with runserver 0.0.0.0:8080 gives ERR_CONNECTION_REFUSED from local or remote (even with the apache2 service stopped).
Edit: I don't think it's Apache, I've reproduced the problem on a clean server with no Apache installed, so unless Apache somehow modified something under source control it's not that
My knowledge of web details is hazy, I don't even know where to troubleshoot this problem - the devserver runs (runserver prints as expected and doesn't give any errors) but never receives a request, I have nothing in iptables.

Sorry for anyone who read this, it would probably have been impossible to solve given my supplied information.
What had actually happened was that I'd been having to modify my wsgi.py script in order to make it happy inside the Apache server, and I'd added a line which said "os.system('/bin/bash --rcfile )" to try and make sure that when running inside apache it got the virtualenv activated.
This line must have been causing some strange problem, another symptom was that I realised when I was running "runserver", it wasn't crashing the the python process was backgrounding itself, where normally it runs inside that console window.
Thanks everyone who asked questions helping me debug!

How to debug remote python script?

I am looking for a way to debug remote python script without any set up like in the answer here
I set remote interpreter, set up a debug configuration, click a debug button and got error Event not found:
ssh://myuser#my_ip:my_port/usr/local/bin/python -u /myuser/.pycharm_helpers/pydev/pydevd.py --multiproc --qt-support --client '0.0.0.0' --port 46994 --file /opt/my_work_dir/my_script.py
/: Event not found.
Seems like pyCharm takes care about all debug setting --multiproc --qt-support --client '0.0.0.0' --port 46994 but I have the wrong configuration.
Is there a way how to debug python script without putting pydevd.settrace('host', port=21000, stdoutToServer=True, stderrToServer=True) and other actions?

I was able to fix this problem by reinstalling PyCharm.
(# 1 and 5 are optional)
Export minimum settings you want to restore such as Keymap (File > Export Settings)
Uninstall your current PyCharm
Install new PyCharm
Launch new PyCharm and don't import your pre-existing setting at the first start up
Import your settings from the old PyCharm (File > Import Settings)
I guess this happens when some environment related settings are messed up.
Notice that you need to remember your settings for the remote interpreter as it will be gone when reinstalling.

I use vagrant quite often with pycharm and debugging has always worked great for me as long as i setup the interpreter to the one inside the vagrant box running.
If you go to settings->project->project interpreter and then setup a connection to your remote interpreter it will usually install the pycharm-debug.egg etc and you can debug run your project against this interpreter and set breakpoints in pycharm and it will break on those.
Here is their docs on setting this up https://www.jetbrains.com/help/pycharm/2016.1/configuring-remote-python-interpreters.html

I set up remote debugging as described under the section
Remote debug with a remote interpreter
(not the Server!!) and it works very well.
Here the link: https://www.jetbrains.com/help/pycharm/2016.1/remote-debugging.html
You just have to set up the remote interpreter (I used ssh) and then set up your run configurations. Let me know if you need further help.
Here is my run configuration in PyCharm:

It might be the same issue as this. Use bash as your login shell if you use another one like csh or tcsh.