Develop Reference

python -m SimpleHTTPServer no longer working

python -m SimpleHTTPServer 8000 was working fine in order to render my web pages on localhost. When it quit, I used 7800, which also failed eventually, and now no numerical string works. For example, having launched the server using python -m SimpleHTTPServer 7600, I get the following when trying to render through the browser (any browser):
Serving HTTP on 0.0.0.0 port 7600 ...
127.0.0.1 - - [21/Feb/2022 20:14:04] code 404, message File not found
127.0.0.1 - - [21/Feb/2022 20:14:04] "GET /favicon.ico HTTP/1.1" 404 -
127.0.0.1 - - [21/Feb/2022 20:14:19] code 404, message File not found
127.0.0.1 - - [21/Feb/2022 20:14:19] "GET /FrontandBackMatter/css/style.css HTTP/1.1" 404 -
I get this result having changed nothing in the files.

How to run Django with Uvicorn webserver?

I have a Django project running on my local machine with dev server manage.py runserver and I'm trying to run it with Uvicorn before I deploy it in a virtual machine. So in my virtual environment I installed uvicorn and started the server, but as you can see below it fails to find Django static css files.
(envdev) user#lenovo:~/python/myproject$ uvicorn myproject.asgi:application --port 8001
Started server process [17426]
Waiting for application startup.
ASGI 'lifespan' protocol appears unsupported.
Application startup complete.
Uvicorn running on http://127.0.0.1:8001 (Press CTRL+C to quit)
INFO: 127.0.0.1:45720 - "GET /admin/ HTTP/1.1" 200 OK
Not Found: /static/admin/css/base.css
Not Found: /static/admin/css/base.css
INFO: 127.0.0.1:45720 - "GET /static/admin/css/base.css HTTP/1.1" 404 Not Found
Not Found: /static/admin/css/dashboard.css
Not Found: /static/admin/css/dashboard.css
INFO: 127.0.0.1:45724 - "GET /static/admin/css/dashboard.css HTTP/1.1" 404 Not Found
Not Found: /static/admin/css/responsive.css
Not Found: /static/admin/css/responsive.css
INFO: 127.0.0.1:45726 - "GET /static/admin/css/responsive.css HTTP/1.1" 404 Not Found
Uvicorn has an option --root-path so I tried to specify the directory where these files are located but there is still the same error (path is correct). How can I solve this issue?

When not running with the built-in development server, you'll need to either
use whitenoise which does this as a Django/WSGI middleware (my recommendation)
use the classic staticfile deployment procedure which collects all static files into some root and a static file server is expected to serve them. Uvicorn doesn't seem to support static file serving, so you might need something else too (see e.g. https://www.uvicorn.org/deployment/#running-behind-nginx).
(very, very unpreferably!) have Django serve static files like it does in dev

Add below code your settings.py file
STATIC_ROOT = os.path.join(BASE_DIR, 'static', )
Add below code in your urls.py
from django.conf.urls.static import static
from django.conf import settings
urlpatterns = [.
.....] + static(settings.STATIC_URL, document_root=settings.STATIC_ROOT)
Then run below command but static directory must exist
python manage.py collectstatic --noinput
start server
uvicorn main.asgi:application --host 0.0.0.0

flask.cli.NoAppException: Failed to find Flask application or factory in module "flaskr". Use "FLASK_APP=flaskr:name to specify one

I am building a python web application using flask and following tutorial from http://flask.pocoo.org/docs/1.0/tutorial/factory/ . I am running the flask from the parent directory but getting following error.
(venv) E:\python-code\python-web>flask run
* Serving Flask app "flaskr" (lazy loading)
* Environment: development
* Debug mode: on
* Restarting with stat
* Debugger is active!
* Debugger PIN: 294-690-396
* Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)
127.0.0.1 - - [16/Mar/2019 13:10:43] "GET /hello HTTP/1.1" 500 -
Traceback (most recent call last):
File "e:\python-code\python-web\venv\lib\site-packages\flask\_compat.py", line 35, in reraise
raise value
File "e:\python-code\python-web\venv\lib\site-packages\flask\cli.py", line 95, in find_best_app
module=module.__name__
flask.cli.NoAppException: Failed to find Flask application or factory in module "flaskr". Use "FLASK_APP=flaskr:name to specify one.
127.0.0.1 - - [16/Mar/2019 13:10:43] "GET /hello?__debugger__=yes&cmd=resource&f=style.css HTTP/1.1" 200 -
127.0.0.1 - - [16/Mar/2019 13:10:43] "GET /hello?__debugger__=yes&cmd=resource&f=jquery.js HTTP/1.1" 200 -
127.0.0.1 - - [16/Mar/2019 13:10:43] "GET /hello?__debugger__=yes&cmd=resource&f=debugger.js HTTP/1.1" 200 -
127.0.0.1 - - [16/Mar/2019 13:10:43] "GET /hello?__debugger__=yes&cmd=resource&f=ubuntu.ttf HTTP/1.1" 200 -
127.0.0.1 - - [16/Mar/2019 13:10:44] "GET /hello?__debugger__=yes&cmd=resource&f=console.png HTTP/1.1" 200 -
127.0.0.1 - - [16/Mar/2019 13:10:44] "GET /hello?__debugger__=yes&cmd=resource&f=console.png HTTP/1.1" 200 -
Please help.
I have tried Running Flask app from cli gives "no module named flaskr"
and
flask.cli.NoAppException: Failed to find application in module?

I have found my problem. I was missing return app as the last statement in my code. Sorry for confusion and apologies.

I got that error
flask.cli.NoAppException flask.cli.NoAppException: Failed to find
Flask application or factory in module "flaskr". Use
"FLASK_APP=flaskr:name to specify one.
I tried all answers, and it got resolved after I changed the function name from create_function to create_app

I followed the instructions just like the official tutorial said but still got the same error.
My problem was with the IDE that I was using ( Pycharm )
Even though I had an init.py file in the flaskr directory, it still wasn't considered as a package.
So I deleted the flaskr directory and created a "new package". Then just copy the code in the init.py and that'll solve the problem

is your application dir not named properly? for example, if you wrote FLASK_APP=flaskr but your project name is something else, you will get this error. Also, what is in your flaskr/flaskr/__init__.py file if the project is named flaskr like in the tutorial?

You can't name the FLASK_APP enviroment var as Flask.py. Try with another name please and try again.
No puedes poner el nombre de la variable de ambiente FLASK_APP como Flask.py. Prueba cambiando el nombre del archivo.

Depending on the OS you are using you need to export flaskr in your environment
For Linux and Mac:
export FLASK_APP=flaskr
export FLASK_ENV=development
flask run
For Windows cmd, use set instead of export:
set FLASK_APP=flaskr
set FLASK_ENV=development
flask run
For Windows PowerShell, use $env: instead of export:
$env:FLASK_APP = "flaskr"
$env:FLASK_ENV = "development"
flask run```

Flask can't find/run my app even though its in my Pythonpath

I have a very simple Flask app setup locally but when I try to run it I get this error:
NoAppException: The file/path provided (cowork_map) does not appear to exist. Please verify the path is correct. If app is not on PYTHONPATH, ensure the extension is .py
Im in a virtual env with flask and all other requirements installed and up to date, I have added the path to my project folder to my $PYTHONPATH and have checked that its there.
I have also used the second answer here to force check if its in my sys.path:
How to add something to PYTHONPATH?
I have tried force running it with 'python -m flask run' as advised here
Flask can't find app file
I ran export 'FLASK_APP=myapp.py' as advised in the official docs.
I have also tried running with with 'FLASK_DEBUG=1' and this is the output:
127.0.0.1 - - [05/Mar/2017 16:55:13] "GET /? __debugger__=yes&cmd=resource&f=style.css HTTP/1.1" 200 -
127.0.0.1 - - [05/Mar/2017 16:55:13] "GET /?__debugger__=yes&cmd=resource&f=jquery.js HTTP/1.1" 200 -
127.0.0.1 - - [05/Mar/2017 16:55:13] "GET /?__debugger__=yes&cmd=resource&f=debugger.js HTTP/1.1" 200 -
127.0.0.1 - - [05/Mar/2017 16:55:13] "GET /?__debugger__=yes&cmd=resource&f=ubuntu.ttf HTTP/1.1" 200 -
127.0.0.1 - - [05/Mar/2017 16:55:13] "GET /?__debugger__=yes&cmd=resource&f=console.png HTTP/1.1" 200 -
127.0.0.1 - - [05/Mar/2017 16:55:13] "GET /?__debugger__=yes&cmd=resource&f=console.png HTTP/1.1" 200 -
Whats even stranger is that I have another Flask project folder with its own env and that runs just fine, I can't see whats different with this one though.
I should add that everything in my app file is setup correctly with a Flask app initialized.
Also, if I run 'python -mflask run' (with DEBUG on) I get this error on the page when viewed locally:
__main__.NoAppException
but just 'flask run' displays this:
flask.cli.NoAppException

OK I figured this out, I have both Python 2.7 and 3 on my machine and there was a module I had imported that was installed on the other version of Python to the one I was using in my env. A very noob error I suppose!

Problems with Django static files

I have downloaded this project and trying to make it work: http://sourceforge.net/p/etconf/git/ci/master/tree/
The problem is, after I managed to install all prerequisites, it runs, but does not load staticfiles. According to settings it should look for them in the /media directory, but however I tried to change MEDIA_ROOT, STATIC_URL and various different parameters in settings.py it shows in the console:
[09/Oct/2015 10:56:08] "GET /static/configurator/admin/css/base.css HTTP/1.1" 404 2281
[09/Oct/2015 10:56:08] "GET /static/configurator/configurator.css HTTP/1.1" 404 2275
[09/Oct/2015 10:56:08] "GET /static/configurator/prototype.js HTTP/1.1" 404 2263
[09/Oct/2015 10:56:08] "GET /static/configurator/configurator.js HTTP/1.1" 404 2272
What am I doing wrong? Maybe it's some sort of old bug or something (project is using python 2 and django 1.1)

I guess you missed to run below command after configuration:
python manage.py collectstatic
What I see is you get 404 error for static files which means that the files are not located where it is been searched for.