I am using python anywhere to host a flask app that has 2 components: 1) a website to show some stuff from a txt file and 2) a python script to do some API stuff and change the data in the txt file.
Currently, I can run both of these separately without issue but I cannot use them together. I have tried to use threading but it doesn't work.
Basically, the background script (part 2) is in backend.py called by mainloop() consists of some API calls to other websites, modifying the txt file then sleeping for an hour.
wsgi.py
import sys
path = '/home/michalis95/API-updater'
if path not in sys.path:
sys.path.append(path)
from threading import Thread
import website
application = website.create_app()
/website/__init.py__
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from os import path
from threading import Thread
from flask_login import LoginManager
db = SQLAlchemy()
DB_NAME = "database.db"
def create_app():
app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = f'sqlite:///{DB_NAME}'
db.init_app(app)
from .views import views
from .auth import auth
app.register_blueprint(views, url_prefix='/')
app.register_blueprint(auth, url_prefix='/')
from .models import User, Note
create_database(app)
login_manager = LoginManager()
login_manager.login_view = 'auth.login'
login_manager.init_app(app)
#login_manager.user_loader
def load_user(id):
return User.query.get(int(id))
import backend
def run():
t=Thread(target=backend.mainloop())
t.start()
run()
return app
def create_database(app):
if not path.exists('website/' + DB_NAME):
db.create_all(app=app)
print('Created Database!')
backend.py
def mainloop():
while True:
#do stuff
time.sleep(3600)
You might need to look into Always-on tasks,
"Always-on tasks are scripts that are kept running all the time, and restarted if they crash."
I use them, they are really effective.Depending on the plan you have, They cost about a buck per month, but they do the job.
The problem was in
def run():
t=Thread(target=backend.mainloop())
...
it should be
def run():
t=Thread(target=backend.mainloop())
...
Related
I am trying to find a way to structure my code such that I can view logs in the production server hosted on Heroku.
Every tutorial I found seems to do logging like this:
How to show stdout logs in Heroku using Flask?
However, I am using the application factory pattern which utilizes Blueprints. As such here are some sample:
main.py
from app import create_app
app = create_app()
if __name__ == "__main__":
app.run()
app/_ _ init _ _.py
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
...
db = SQLAlchemy()
...
def create_app():
app = Flask(__name__)
...
db.init_app(app)
from .routes.demo_blueprint import demo_blueprint
...
# Register the routes to the Flask object
app.register_blueprint(demo_blueprint)
...
app/routes/demo_blueprint.py
from app import db
...
demo_blueprint = Blueprint('demo_blueprint', __name__)
#demo_blueprint.route('/demo', methods=['GET'])
...
In order to perform logging at the blueprint level, I would need to import app from main.py. However, this would cause an import error since __init__.py imports the blueprint before app is created. I was wondering if there were any work arounds for this.
Turns out it was a simple fix. To access the application context in the Blueprint, just use current_app. Following the example:
How to show stdout logs in Heroku using Flask?
main.py
from app import create_app
app = create_app()
if __name__ == "__main__":
app.run()
app/_ _ init _ _.py
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
...
db = SQLAlchemy()
...
def create_app():
app = Flask(__name__)
if __name__ != '__main__':
gunicorn_logger = logging.getLogger('gunicorn.error')
app.logger.handlers = gunicorn_logger.handlers
app.logger.setLevel(gunicorn_logger.level)
...
db.init_app(app)
from .routes.demo_blueprint import demo_blueprint
...
# Register the routes to the Flask object
app.register_blueprint(demo_blueprint)
...
app/routes/demo_blueprint.py
from flask import ***current_user***
from app import db
...
demo_blueprint = Blueprint('demo_blueprint', __name__)
#demo_blueprint.route('/demo', methods=['GET'])
def demo():
current_app.logger.debug('debug message: %s', 'test')
...
I am getting the following error when trying to set up a scheduled job for my flask app:
This typically means that you attempted to use functionality that needed
to interface with the current application object in some way. To solve
this, set up an application context with app.app_context(). See the
documentation for more information.
I have tried to include the function 'print_session' (which is just a dummy function to check the session data will pull through - in reality this function will query a database) with a 'current_app.appcontext() with loop as I have seen on a few other apps but no joy. Does anyone know why it is still out of the application context?
main.py
from website import create_app
app = create_app()
if __name__=="__main__":
app.run(debug=True,host='localhost',port=5000,threaded=True)
init.py
from flask import Flask, session
from flask_sqlalchemy import SQLAlchemy
from os import path
from flask_session import Session
from flask_login import LoginManager
import redis
db = SQLAlchemy()
DB_NAME = 'sqlite:///db.sqlite3'
sess=Session()
login_manager = LoginManager()
def create_app():
app = Flask(__name__)
app.config['SECRET_KEY'] = "SECRET_KEY"
app.config['SQLALCHEMY_DATABASE_URI'] = SQLALCHEMY_DATABASE_URI
app.config['SESSION_TYPE'] = 'SESSION_TYPE'
app.config['SESSION_REDIS'] = 'SESSION_REDIS'
db.init_app(app)
sess.init_app(app)
login_manager.login_view = 'auth.login'
login_manager.init_app(app)
# with app.app_context():
from .views import views
from .auth import auth
app.register_blueprint(views,url_prefix='/')
app.register_blueprint(auth,url_prefix='/')
from .models import User,Token
create_database(app)
return app
def create_database(app):
db.create_all(app=app)
print('Created database')
views.py
from flask import Blueprint,render_template,session,redirect,request,url_for
from flask import current_app
from apscheduler.schedulers.background import BackgroundScheduler
from apscheduler.schedulers.blocking import BlockingScheduler
import datetime
from flask_login import login_required,current_user
from requests_oauthlib import OAuth2Session
from . import db
from .models import Token
from functools import wraps
def print_session(value):
with current_app.app_context():
print('Yes',value)
return(redirect(url_for('views.home')))
#views.route('/start_schedule')
#login_required
def start_xero_schedule():
with app.app_context():
sched = BackgroundScheduler()
sched.add_job(print_session,'interval',args=[session['value']],seconds=10)
sched.start()
return(redirect(url_for('views.xero')))
I have an extremely large application that is factored into many blueprints. I need to configure the entire application to save files into a directory when a user uploads files. So I am setting ["SESSION_FILE_DIR"] = 'C:/some/path' to the path where files would live after upload in the app.py file.
The documentation reads that configuration settings are shared across the blueprints. I'm experiencing one issue that is not working and below is a stripped down example to replicate my problem to support my question. So, to debug I've created an extremely simple version just printing the path to screen to see what is happening.
If I head over to the URL .../print_dir then the ["SESSION_FILE_DIR"] = 'C:/some/path' is printed to screen. However, if I head over to the URL defined within the blueprint .../new then I am given an error of NameError: name 'server' is not defined.
How can I configure my app such that the same ["SESSION_FILE_DIR"] can be used across blueprints?
The contents of my main app.py are as follows:
from flask import Flask, render_template, request, session
from flask_session import Session
import tempfile
server = Flask(__name__)
server.config["SESSION_PERMANENT"] = False
server.config["SESSION_TYPE"] = "filesystem"
server.config["SESSION_FILE_DIR"] = 'C:/some/path'
server.secret_key = 'abcdefg'
### Import and Register Blueprints
from tools.routes import my_bp
server.register_blueprint(my_bp)
#server.route('/')
def homepage():
return "Hello"
#server.route('/print_dir')
def homepage2():
return server.config["SESSION_FILE_DIR"]
if __name__ == '__main__':
server.run(debug=True)
and now suppose the blueprint lives in a subdirectory called tools and contains the following:
from flask import Flask, render_template, request, session, Blueprint
from flask_session import Session
my_bp = Blueprint("my_bp", __name__)
#my_bp.route('/new', methods=['POST', 'GET'])
def path():
path = server.config["SESSION_FILE_DIR"]
return path
To access the app.config from within a Blueprint, you can import current_app from flask.
Example:
# ./app.py
from flask import Flask
from views.blueprint import bp
app = Flask(__name__)
# Set the config you want:
app.config['IMPORTANT_DIRECTORY'] = '~/path/to/important/directory'
# Register your blueprint
app.register_blueprint(bp)
# ./views/blueprint.py
from flask import Blueprint, current_app
bp = Blueprint('bp', __name__)
#bp.route('/path')
def get_path():
# access the config
path = current_app.config['IMPORTANT_DIRECTORY']
return path
You can find more info in the api docs for flask.
I want to set up a basic admin interface using flask-admin, and I want all of this to sit in a blueprint. Here's a minimal version my code:
#app.py
from flask import Flask
from bp import bp
app = Flask(__name__)
app.register_blueprint(bp)
if __name__ == "__main__":
app.run(debug=True)
#bp.py
from flask import Blueprint, current_app
from flask_admin import Admin
from flask_admin.contrib.pymongo import ModelView
import pymongo
conn = pymongo.MongoClient()
bp = Blueprint('bp', __name__,
template_folder='templates')
admin = Admin(current_app)
admin.add_view(ModelView(conn.my_db.my_collection))
When running python app.py, it crashes with RuntimeError: working outside of application context, because admin is in no way hooked (or whatever word is used to describe that) to bp.
Normally, one would write
#bp.route('/<page>')
def show(page):
pass
But I can't find the right decorator in the context of creating an Admin object. One thing I tried is to do admin = Admin() in bp.py, import admin in app.py and then admin.app = app in app.py. That works, but it feels like I'm splitting logic in several files, so I'm not really comfortable with that. What's the pythonic way to deal with this situation?
You need the actual app object to init the Flask admin Class. Current_app won't work. This call should be placed on app.py. Then on the blueprint you can use
from app import admin
It work out in this way. just for your reference.
#YourApp/init.py
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_admin import Admin
db = SQLAlchemy()
admin = Admin(name='TuozhanOA', template_mode='bootstrap3')
def create_app(config_class=Config):
app = Flask(name)
app.config.from_object(Config)
db.init_app(app)
admin.init_app(app)
from YourApp.main.routes import main
app.register_blueprint(main)
from YourApp.adminbp.routes import adminbp, user_datastore
app.register_blueprint(adminbp)
security = Security(app, user_datastore)
return app
#YourApp/adminbp/routes.py
from flask import render_template, Blueprint
from YourApp.models import User, Role
from YourApp import db, admin
from flask_admin.contrib.sqla import ModelView
from wtforms.fields import PasswordField
from flask_admin.contrib.fileadmin import FileAdmin
import os.path as op
from flask_security import current_user, login_required, RoleMixin, Security,
SQLAlchemyUserDatastore, UserMixin, utils
adminbp = Blueprint('adminbp', name)
admin.add_view(ModelView(User, db.session, category="Team"))
admin.add_view(ModelView(Role, db.session, category="Team"))
path = op.join(op.dirname(file), 'tuozhan')
admin.add_view(FileAdmin(path, '/static/tuozhan/', name='File Explore'))
I am trying to integrate Flask-SocketIO with my Flask application.
For some reason I am getting an import error that is triggered by the
from .. import socketio that I have in my events.py and I am not sure why.
I would greatly appreciate any help provided.
app.py
from factory import create_app
app = create_app()
factory.py
from flask import Flask
from flask.ext.socketio import SocketIO
from flask.ext.login import LoginManager
import os
from celery import Celery
lm = LoginManager()
socketio = SocketIO()
lm.login_view = 'main.login'
lm.session_protection = 'strong'
def create_app():
app = Flask(__name__)
app.config.from_object(os.environ.get('APP_CONFIG')) # export APP_CONFIG=settings.Development
lm.init_app(app)
from project.main import main as main_blueprint
app.register_blueprint(main_blueprint)
socketio.init_app(app)
return app
main/____init____.py
from flask import Blueprint
main = Blueprint('main', __name__)
import views, events
main/events.py
# from __future__ import absolute_import
from uuid import uuid4
from flask import current_app, session, request
from flask.ext.socketio import emit, disconnect
from .. import socketio
#socketio.on('status', namespace='/events')
def events_message(message):
print 'socketio.on: status'
emit('status', {'status': message['status']})
#socketio.on('disconnect request', namespace='/events')
def disconnect_request():
print 'socketio.on: disconnect request'
emit('status', {'status': 'Disconnected!'})
disconnect()
#socketio.on('connect', namespace='/events')
def events_connect():
print 'socketio.on: connect'
websocket_id = str(uuid4())
session['websocket_id'] = websocket_id
current_app.clients[websocket_id] = request.namespace
emit('websocket_id', {'websocket_id': websocket_id})
Rename main/____init____.py to main/__init__.py and you can do:
from . import socketio
if socketio is defined in __init__.py like you said. However, it looks like it's defined in factory.py, in which case you'd do:
from ..factory import socketio