Application Factory Pattern: AttributeError: 'tuple' object has no attribute 'shell_context_processor' [closed] - python-3.x

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I am trying to cast my Flask app into a App Factory Pattern, but I got stuck on the following error:
Traceback (most recent call last):
File "/usr/local/bin/flask", line 8, in <module>
sys.exit(main())
File "/usr/local/lib/python3.7/site-packages/flask/cli.py", line 967, in main
cli.main(args=sys.argv[1:], prog_name="python -m flask" if as_module else None)
File "/usr/local/lib/python3.7/site-packages/flask/cli.py", line 586, in main
return super(FlaskGroup, self).main(*args, **kwargs)
File "/usr/local/lib/python3.7/site-packages/click/core.py", line 782, in main
rv = self.invoke(ctx)
File "/usr/local/lib/python3.7/site-packages/click/core.py", line 1259, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File "/usr/local/lib/python3.7/site-packages/click/core.py", line 1066, in invoke
return ctx.invoke(self.callback, **ctx.params)
File "/usr/local/lib/python3.7/site-packages/click/core.py", line 610, in invoke
return callback(*args, **kwargs)
File "/usr/local/lib/python3.7/site-packages/click/decorators.py", line 73, in new_func
return ctx.invoke(f, obj, *args, **kwargs)
File "/usr/local/lib/python3.7/site-packages/click/core.py", line 610, in invoke
return callback(*args, **kwargs)
File "/usr/local/lib/python3.7/site-packages/flask/cli.py", line 848, in run_command
app = DispatchingApp(info.load_app, use_eager_loading=eager_loading)
File "/usr/local/lib/python3.7/site-packages/flask/cli.py", line 305, in __init__
self._load_unlocked()
File "/usr/local/lib/python3.7/site-packages/flask/cli.py", line 330, in _load_unlocked
self._app = rv = self.loader()
File "/usr/local/lib/python3.7/site-packages/flask/cli.py", line 388, in load_app
app = locate_app(self, import_name, name)
File "/usr/local/lib/python3.7/site-packages/flask/cli.py", line 240, in locate_app
__import__(module_name)
File "/home/chrdina/python/werda/werda.py", line 7, in <module>
#app.shell_context_processor
AttributeError: 'tuple' object has no attribute 'shell_context_processor'
I tried to find out where the AttributeError happens, but I'm totally stuck. I don't unterstand where the mentioned tuple is located in my code. I tried deleting the shell_context_processor part, but then the app seems to not know it's an app at all and throws this "Error: Failed to find Flask application or factory in module "werda". Use "FLASK_APP=werda:name to specify one.").
If I then try to export FLASK_APP again (it's already set in my .flaskenv) nothing changes.
I define the shell_context_processor in my werda.py (which is my app) in the top level of my directory.
werda.py:
from app import create_app, db
from app.models import User, Role, Employee, Language, Employee_Languages, Attendance, AttendanceArchive
app = create_app()
#app.shell_context_processor
def make_shell_context():
return {'db': db, 'User': User, 'Role': Role, 'Employee':Employee, 'Language':Language, 'Employee_Languages':Employee_Languages, 'Attendance':Attendance, 'AttendanceArchive':AttendanceArchive}
init.py:
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate
from flask_admin import Admin
from flask_bootstrap import Bootstrap
from flask_security import Security, SQLAlchemyUserDatastore
from flask_mail import Mail
import logging
from logging.handlers import SMTPHandler, RotatingFileHandler
import os
from config import Config
db = SQLAlchemy()
migrate = Migrate()
bootstrap = Bootstrap()
from app.models import User, Role
user_datastore = SQLAlchemyUserDatastore(db, User, Role)
security = Security()
mail = Mail()
admin = Admin()
def create_app(config_class=Config):
app=Flask(__name__)
app.config.from_object(Config)
db.init_app(app)
migrate.init_app(app, db)
from app.models import User, Role
user_datastore = SQLAlchemyUserDatastore(db, User, Role)
security.init_app(app, user_datastore)
bootstrap.init_app(app)
mail.init_app(app)
app.config['FLASK_ADMIN_SWATCH'] = 'cerulean'
from app.errors import bp as errors_bp
app.register_blueprint(errors_bp)
from app.main import bp as main_bp
app.register_blueprint(main_bp)
admin = Admin(app, name='werda', template_mode='bootstrap3')
#send errors via mail:
if not app.debug:
if app.config['MAIL_SERVER']:
auth = None
if app.config['MAIL_USERNAME'] or app.config['MAIL_PASSWORD']:
auth = (app.config['MAIL_USERNAME'], app.config['MAIL_PASSWORD'])
secure = None
if app.config['MAIL_USE_TLS']:
secure = ()
mail_handler = SMTPHandler(
mailhost=(app.config['MAIL_SERVER'], app.config['MAIL_PORT']),
fromaddr='no-reply#' + app.config['MAIL_SERVER'],
toaddrs=app.config['ADMINS'], subject='werda Failure',
credentials=auth, secure=secure)
mail_handler.setLevel(logging.ERROR)
app.logger.addHandler(mail_handler)
#save errors to log file:
if not os.path.exists('logs'):
os.mkdir('logs')
file_handler = RotatingFileHandler('logs/werda.log', maxBytes=10240,
backupCount=10)
file_handler.setFormatter(logging.Formatter(
'%(asctime)s %(levelname)s: %(message)s [in %(pathname)s:%(lineno)d]'))
file_handler.setLevel(logging.INFO)
app.logger.addHandler(file_handler)
app.logger.setLevel(logging.INFO)
app.logger.info('werda startup')
return app, admin
from app import models
Directory Structure
.
├── app
│   ├── cli.py
│   ├── errors
│   │   ├── handlers.py
│   │   ├── __init__.py
│   │   └── __pycache__
│   ├── __init__.py
│   ├── __init__.pyc
│   ├── main
│   │   ├── forms.py
│   │   ├── __init__.py
│   │   ├── __pycache__
│   │   └── routes.py
│   ├── models.py
│   └── templates
│   ├── addnextweek.html
│   ├── base.html
│   ├── errors
│   │   ├── 403.html
│   │   ├── 404.html
│   │   └── 500.html
│   ├── index.html
│   ├── movetoarchive.html
│   ├── nextweek.html
│   ├── now.html
│   ├── russ.html
│   ├── security
│   │   ├── login_user.html
│   │   └── register_user.html
│   ├── thisweek.html
│   ├── thisweek_working.html
│   └── today.html
├── app.db
├── config.py
├── libc6_2.31-0ubuntu8+lp1871129~1_amd64.deb
├── README.md
├── requirements.txt
├── werda.py

Answer 1

Consider to use the init_app() function in your factory function. You also should modify your app.config.from_object(Config) to app.config.from_object(class_config)
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate
from flask_admin import Admin
from flask_bootstrap import Bootstrap
from flask_security import Security, SQLAlchemyUserDatastore
from flask_mail import Mail
import logging
from logging.handlers import SMTPHandler, RotatingFileHandler
import os
from config import Config
from app.models import User, Role #<-----------repositioned
db = SQLAlchemy()
migrate = Migrate()
bootstrap = Bootstrap()
user_datastore = SQLAlchemyUserDatastore() #<-------------modified
security = Security()
mail = Mail()
admin = Admin()
def create_app(config_class=Config):
app=Flask(__name__)
app.config.from_object(class_config) #<------modified
db.init_app(app)
migrate.init_app(app, db)
user_datastore.init_app = SQLAlchemyUserDatastore(app, db, User, Role) #<-------modified
security.init_app(app, user_datastore)
bootstrap.init_app(app)
mail.init_app(app)
app.config['FLASK_ADMIN_SWATCH'] = 'cerulean'
from app.errors import bp as errors_bp
app.register_blueprint(errors_bp)
from app.main import bp as main_bp
app.register_blueprint(main_bp)
admin = Admin(app, name='werda', template_mode='bootstrap3')
#send errors via mail:
if not app.debug:
if app.config['MAIL_SERVER']:
auth = None
if app.config['MAIL_USERNAME'] or app.config['MAIL_PASSWORD']:
auth = (app.config['MAIL_USERNAME'], app.config['MAIL_PASSWORD'])
secure = None
if app.config['MAIL_USE_TLS']:
secure = ()
mail_handler = SMTPHandler(
mailhost=(app.config['MAIL_SERVER'], app.config['MAIL_PORT']),
fromaddr='no-reply#' + app.config['MAIL_SERVER'],
toaddrs=app.config['ADMINS'], subject='werda Failure',
credentials=auth, secure=secure)
mail_handler.setLevel(logging.ERROR)
app.logger.addHandler(mail_handler)
#save errors to log file:
if not os.path.exists('logs'):
os.mkdir('logs')
file_handler = RotatingFileHandler('logs/werda.log', maxBytes=10240,
backupCount=10)
file_handler.setFormatter(logging.Formatter(
'%(asctime)s %(levelname)s: %(message)s [in %(pathname)s:%(lineno)d]'))
file_handler.setLevel(logging.INFO)
app.logger.addHandler(file_handler)
app.logger.setLevel(logging.INFO)
app.logger.info('werda startup')
return app, admin
from app import models

Answer 2

I got it!
I return'ed app and admin in create_app(), which caused the problem. And it seems that's also where the mysterious Tuple was situated.
If create_app() only return's app my app starts as it should. Now to work out how to run flask-admin correctly.
Corrected code for now:
init.py:
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate
from flask_admin import Admin
from flask_bootstrap import Bootstrap
from flask_security import Security, SQLAlchemyUserDatastore
from flask_mail import Mail
import logging
from logging.handlers import SMTPHandler, RotatingFileHandler
import os
from config import Config
db = SQLAlchemy()
migrate = Migrate()
bootstrap = Bootstrap()
from app.models import User, Role
user_datastore = SQLAlchemyUserDatastore(db, User, Role)
security = Security()
mail = Mail()
admin = Admin()
def create_app(config_class=Config):
app=Flask(__name__)
app.config.from_object(Config)
db.init_app(app)
migrate.init_app(app, db)
from app.models import User, Role
user_datastore = SQLAlchemyUserDatastore(db, User, Role)
security.init_app(app, user_datastore)
bootstrap.init_app(app)
mail.init_app(app)
app.config['FLASK_ADMIN_SWATCH'] = 'cerulean'
from app.errors import bp as errors_bp
app.register_blueprint(errors_bp)
from app.main import bp as main_bp
app.register_blueprint(main_bp)
admin = Admin(app, name='werda', template_mode='bootstrap3')
#send errors via mail:
if not app.debug:
if app.config['MAIL_SERVER']:
auth = None
if app.config['MAIL_USERNAME'] or app.config['MAIL_PASSWORD']:
auth = (app.config['MAIL_USERNAME'], app.config['MAIL_PASSWORD'])
secure = None
if app.config['MAIL_USE_TLS']:
secure = ()
mail_handler = SMTPHandler(
mailhost=(app.config['MAIL_SERVER'], app.config['MAIL_PORT']),
fromaddr='no-reply#' + app.config['MAIL_SERVER'],
toaddrs=app.config['ADMINS'], subject='werda Failure',
credentials=auth, secure=secure)
mail_handler.setLevel(logging.ERROR)
app.logger.addHandler(mail_handler)
#save errors to log file:
if not os.path.exists('logs'):
os.mkdir('logs')
file_handler = RotatingFileHandler('logs/werda.log', maxBytes=10240,
backupCount=10)
file_handler.setFormatter(logging.Formatter(
'%(asctime)s %(levelname)s: %(message)s [in %(pathname)s:%(lineno)d]'))
file_handler.setLevel(logging.INFO)
app.logger.addHandler(file_handler)
app.logger.setLevel(logging.INFO)
app.logger.info('werda startup')
return app #deleted admin here
from app import models