The beginning of the data in the template gives a clue to what’s happening. ' is the HTML entity for a single quote ‘. Combined with the preceding b, b’, it looks like the representation of a byte string, rather than the contents of the string. Decode the byte string to a string before trying … Read more
The downside of your approach is that there are many ways it could fail especially around stopping and restarting your flask application. You will have to deal with graceful shutdown to give your worker a chance to finish its current task. Sometime your worker won’t stop on time and might linger while you start another … Read more
Your code has the line from app.models import User in __init__.py. The problem is that app.models has from . import db. This is a circular import: __init__ tries to import User, which tries to import db, which isn’t defined until after __init__ tries to import User. To solve this, move your local app imports below … Read more
The main idea here is to assign the choices list to the field after instantiation. To do so you need to use argument coerce=int. The coerce keyword arg to SelectField says that we use int() to coerce form data. The default coerce is unicode(). Correct FormModel: class AddName(FlaskForm): name =StringField(‘Device name’, validators=[InputRequired(),Length(min=4, max=30)]) groupID = … Read more
There are several ways to do this. send_file and then immediately delete (Linux only) Flask has an after_this_request decorator which could work for this use case: @app.route(‘/files/<filename>/download’) def download_file(filename): file_path = derive_filepath_from_filename(filename) file_handle = open(file_path, ‘r’) @after_this_request def remove_file(response): try: os.remove(file_path) file_handle.close() except Exception as error: app.logger.error(“Error removing or closing downloaded file handle”, error) return … Read more
The mobiusklein answers is pretty good, but there is “hack” you should consider. Define your Javascript method to receive params and send data as params to your function. main.py @app.route(“https://stackoverflow.com/”) def hello(): data = {‘username’: ‘Pang’, ‘site’: ‘stackoverflow.com’} return render_template(‘settings.html’, data=data) app.js function myFunc(vars) { return vars } settings.html <html> <head> <script type=”text/javascript” {{ url_for(‘static’, … Read more
Ok, found it: If a tuple is returned the items in the tuple can provide extra information. Such tuples have to be in the form (response, status, headers). The status value will override the status code and headers can be a list or dictionary of additional header values. (Flask docs.) So return (resp.text, resp.status_code, resp.headers.items()) … Read more
I have created people_photo in static folder and placed an image named shovon.jpg. From the application.py I passed the image as variable to template and showed it using img tag in the template. In application.py: from flask import Flask, render_template import os PEOPLE_FOLDER = os.path.join(‘static’, ‘people_photo’) app = Flask(__name__) app.config[‘UPLOAD_FOLDER’] = PEOPLE_FOLDER @app.route(“https://stackoverflow.com/”) @app.route(‘/index’) def … Read more
I fixed the problem with the help of the Application Factory pattern. I declare the database in a third module and configure it later in the same module in which I start the application. This results in the following imports: database.py → app.py views.py → app.py database.py → views.py There is no circular import. It … Read more
Flask-WTF adds a CSRF protection field. If it’s not present, the CSRF validation will fail, and the form will be invalid. Use form.hidden_tag() to include any hidden fields in your form (including the CSRF field). <form method=”post”> {{ form.hidden_tag() }} … In general, if a form is not validating, you should check form.errors after calling … Read more