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How to remove older css files after webassets rebuilds the scss for a python flask app?

I have a Python 3.9 flask app which uses the flask_assets library.
My flask init.py file looks like:
import logging
import os
from flask import Flask, request, current_app
from config import Config
from flask_assets import Environment
from app.utils.assets import bundles
def create_app(config_class=Config):
app = Flask(__name__)
app.config.from_object(config_class)
assets = Environment(app)
assets.debug = True
assets.versions = 'timestamp'
# assets.cache = False
from app.main import bp as main_bp
app.register_blueprint(main_bp)
assets.register(bundles)
if not app.debug and not app.testing:
app.logger.setLevel(logging.INFO)
app.logger.info('Application starting.')
return app
Since flask_assets is built on top of webassets, I import the Environment and a css Bundle I created which compiles my scss code to css.
Here is how my Bundle looks like:
from flask_assets import Bundle
bundles = {
'css': Bundle (
'scss/_main.scss',
'scss/_base.scss',
'scss/_typography.scss',
'scss/_page_home.scss',
'scss/_page_technote.scss',
filters='pyscss',
depends=('**/*.scss'),
output='css/style.%(version)s.scss.css'
)
}
The problem I have:
Every time I make a change to my scss files, the css successfully rebuilds with a new version for cache busting. However, the older css files remain.
What's the best automatic way to remove them every time a rebuild happens? Is there any reason for keeping the older files?
Also - side question - is it possible for the Bundle object to automatically consider all files of certain type in a directory? Rather than me listing every file individually?
Here is how my files look like:
Thank you!

You can use rmtree. Even though I believe a better way exists, this does it.
from os.path import join
from shutil import rmtree
app = Flask(__name__)
rmtree(join(app.static_folder, 'css'), ignore_errors=True)
You can improve this by checking the file meta by date or similar to not delete the unchanged ones.

How to access app library via iPython for a Flask application?

I have a Flask project where the entry point is application.py and then I have several other modules like, e.g. variant.py, etc.
The project structure is:
>my_app_dir/
application.py
views/
__init__.py
users.py
variant.py
...
For variant.py, it's a function like:
import ...
from views import *
def variant(variant_id, subset='all', language='en'):
...
if subset == 'all':
return json.dumps(x)
return json.dumps([{subset: y[subset]} for y in x])
The point is I want to use variant.py like an API, so I am testing via iPython, something like, but it's returning an error:
from views import variant as v
aa = v.variant('22-38212762-A-G')
...
RuntimeError: Working outside of request context.
This typically means that you attempted to use functionality that needed
an active HTTP request. Consult the documentation on testing for
information about how to avoid this problem.
I've tried googling but couldn't find any similar case, yet I experimented several things for no avail.

In the end, I found out a way to get what I was looking for:
from views import application, autocomplete
from views.variant import variant
ctx = application.test_request_context(path='/login',method='POST', data={'user':'demo','password':'demo123'})
ctx.push()
variant('22-38212762-A-G')[:50]
autocomplete.autocomplete('ttll','gene').json
So, essentially, the trick bit is:
ctx = application.test_request_context(path='/login',method='POST', data={'user':'demo','password':'demo123'})
ctx.push()

Retrieving config from a blueprint in Sanic app

I have a Sanic application, and want to retrieve app.config from a blueprint as it holds MONGO_URL, and I will pass it to a repository class from the blueprint.
However, I could not find how to get app.config in a blueprint. I have also checked Flask solutions, but they are not applicable to Sanic.
My app.py:
from sanic import Sanic
from routes.authentication import auth_route
from routes.user import user_route
app = Sanic(__name__)
app.blueprint(auth_route, url_prefix="/auth")
app.blueprint(user_route, url_prefix="/user")
app.config.from_envvar('TWEETBOX_CONFIG')
app.run(host='127.0.0.1', port=8000, debug=True)
My auth blueprint:
import jwt
from sanic import Blueprint
from sanic.response import json, redirect
from domain.user import User
from repository.user_repository import UserRepository
...
auth_route = Blueprint('authentication')
mongo_url = ?????
user_repository = UserRepository(mongo_url)
...
#auth_route.route('/signin')
async def redirect_user(request):
...

The Sanic way...
Inside a view method, you can access the app instance from the request object. And, therefore access your configuration.
#auth_route.route('/signin')
async def redirect_user(request):
configuration = request.app.config
2021-10-10 Update
There are two newer ways to get to the configuration values (or, perhaps more accuratlely getting the application instance from which you can get the configuration). The first version might be more on point to answering the question of how to get to the config from the blueprint. However, the second option is probably the preferred method since it is precisely intended for this kind of use.
Alternative #1
Blueprints have access to the Sanic applications they are attached to beginning with v21.3.
Therefore, if you have a blueprint object, you can trace that back to the application instance, and therefore also the config value.
app = Sanic("MyApp")
bp = Blueprint("MyBlueprint")
app.blueprint(bp)
assert bp.apps[0] is app
The Blueprint.apps property is a set because it is possible to attach a single blueprint to multiple applications.
Alternative #2
Sanic has a built-in method for retrieving an application instance from the global scope beginning in v20.12. This means that once an application has been instantiated, you can retrieve it using: Sanic.get_app().
app = Sanic("MyApp")
assert Sanic.get_app() is app
This method will only work if there is a single Sanic instance available. If you have multiple application instances, you will need to use the optional name argument:
app1 = Sanic("MyApp")
app2 = Sanic("MyOtherApp")
assert Sanic.get_app("MyApp") is app1

I would suggest a slightly different approach, based on the 12 Factor App (very interesting read which, among others, provides a nice guideline on how to protect and isolate your sensitive info).
The general idea is to place your sensitive and configuration variables in a file that is going to be gitignored and therefore will only be available locally.
I will try to present the method I tend to use in order to be as close as possible to the 12 Factor guidelines:
Create a .env file with your project variables in it:
MONGO_URL=http://no_peeking_this_is_secret:port/
SENSITIVE_PASSWORD=for_your_eyes_only
CONFIG_OPTION_1=config_this
DEBUG=True
...
(Important) Add .env and .env.* on your .gitignore file, thus protecting your sensitive info from been uploaded to GitHub.
Create an env.example (be careful not to name it with a . in the beginning, because it will get ignored).
In that file, you can put an example of the expected configuration in order to be reproducible by simply copy, paste, rename to .env.
In a file named settings.py, use decouple.config to read your config file into variables:
from decouple import config
MONGO_URL = config('MONGO_URL')
CONFIG_OPTION_1 = config('CONFIG_OPTION_1', default='')
DEBUG = config('DEBUG', cast=bool, default=True)
...
Now you can use these variables wherever is necessary for your implementation:
myblueprint.py:
import settings
...
auth_route = Blueprint('authentication')
mongo_url = settings.MONGO_URL
user_repository = UserRepository(mongo_url)
...
As a finisher, I would like to point out that this method is framework (and even language) agnostic so you can use it on Sanic as well as Flask and everywhere you need it!

I think you can create a config.py to save your configuration, just like
config.py
config = {
'MONGO_URL'：'127.0.0.1:27017'
}
and use it in app.py
from config import config
mongo_url = config['MONGO_URL']

There is a variable named current_app in Flask. You can use current_app.config["MONGO_URL"].
But I am not familiar with Sanic.

Python/Django generate runtime exception

I'm using werkzeug in a Django project using Apache/mod_wsgi. What I want to do is access the werkzeug python shell without there actually being an error. The only way I can figure to do this is to intentionally cause an error when the url pattern url(r'^admin/shell', forceAnError()) is matched.
Admittedly, intentionally causing an error isn't the optimal course of action, so if there's a way to simply call/import/render/access the werkzeug python shell from a template or something, that would be the better solution.

If you wrap your WSGI application in a werkzeug.debug.DebuggedApplication with evalex on, you'll get a shell available at /console:
from werkzeug.wrappers import Request, Response
from werkzeug.debug import DebuggedApplication
#Request.application
def app(request):
return Response("Normal application, nothing to see here...")
app = DebuggedApplication(app, evalex=True)
# console_path is another optional keyword argument.
# you can guess what it does.

Cant fetch production db results using Google app engine remote_api

Hey, I'm trying to work out with /remote_api with a django-patch app engine app i got running.
i want to select a few rows from my online production app locally.
i cant seem to manage to do so, everything authenticates fine, it doesnt breaks on imports, but when i try to fetch something it just doesnt print anything.
Placed the test python inside my local app dir.
#!/usr/bin/env python
#
import os
import sys
# Hardwire in appengine modules to PYTHONPATH
# or use wrapper to do it more elegantly
appengine_dirs = ['myworkingpath']
sys.path.extend(appengine_dirs)
# Add your models to path
my_root_dir = os.path.abspath(os.path.dirname(__file__))
sys.path.insert(0, my_root_dir)
from google.appengine.ext import db
from google.appengine.ext.remote_api import remote_api_stub
import getpass
APP_NAME = 'Myappname'
os.environ['AUTH_DOMAIN'] = 'gmail.com'
os.environ['USER_EMAIL'] = 'myuser#gmail.com'
def auth_func():
return (raw_input('Username:'), getpass.getpass('Password:'))
# Use local dev server by passing in as parameter:
# servername='localhost:8080'
# Otherwise, remote_api assumes you are targeting APP_NAME.appspot.com
remote_api_stub.ConfigureRemoteDatastore(APP_NAME,
'/remote_api', auth_func)
# Do stuff like your code was running on App Engine
from channel.models import Channel, Channel2Operator
myresults = mymodel.all().fetch(10)
for result in myresults:
print result.key()
it doesn't give any error or print anything. so does the remote_api console example google got. when i print the myresults i get [].

App Engine patch monkeypatches the ext.db module, mutilating the kind names. You need to make sure you import App Engine patch from your script, to give it the opportunity to mangle things as per usual, or you won't see any data returned.