app.py

import os

import click
import sentry_sdk
from flask import Flask, render_template
from flask_debugtoolbar import DebugToolbarExtension
from flask_session import Session
from flask_talisman import Talisman
from flask_migrate import Migrate

from models import db
from web.views import web as web_blueprint
from dash.views import dash as dash_blueprint

app = Flask(__name__)
app.secret_key = '3n13m3@n13myn13m0-{{APP_SLUG}}'

toolbar = DebugToolbarExtension(app)
app.config['DEBUG_TB_INTERCEPT_REDIRECTS'] = False

database_url = os.environ["DATABASE_URL"]
if database_url.startswith("postgres://"):  # https://help.heroku.com/ZKNTJQSK/
    database_url = database_url.replace("postgres://", "postgresql://", 1)

# setup the database
app.config['SQLALCHEMY_DATABASE_URI'] = database_url
app.config['SQLALCHEMY_ENGINE_OPTIONS'] = {
    "connect_args": {"options": "-c timezone=utc"},  # https://stackoverflow.com/a/26106482/625840
}
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
db.init_app(app)

# secure the session cookies
app.config['SESSION_COOKIE_SECURE'] = True
app.config['SESSION_COOKIE_HTTPONLY'] = True
app.config['SESSION_COOKIE_SAMESITE'] = "Lax"

if os.environ.get("REDIS_URL"):
    from cache import redis_connection
    app.config['SESSION_TYPE'] = 'redis'
    app.config['SESSION_REDIS'] = redis_connection
    sess = Session()
    sess.init_app(app)

if os.environ.get("SENTRY_DSN"):
    sentry = sentry_sdk.init(dsn=os.environ["SENTRY_DSN"])

app.register_blueprint(web_blueprint)
app.register_blueprint(dash_blueprint)

import tasks
for name in dir(tasks):
    item = getattr(tasks, name)
    if type(item) == click.core.Command:
        app.cli.add_command(item)

Talisman(app, content_security_policy={
    "default-src": "*"
})

migrate = Migrate(app, db)

# add a timestamp-based cache buster to static files
static_last_update = 0
for directory in os.walk("static/"):
    file_names = directory[2]
    for file_name in file_names:
        if file_name.startswith("."):
            continue  # ignore config files
        ext = file_name.split(".")[-1]
        if ext not in ["css", "js"]:
            continue  # skip fonts and images
        file_path = os.path.join(directory[0], file_name)
        updated_at = os.path.getmtime(file_path)
        if updated_at > static_last_update:
            static_last_update = updated_at
app.config['static_last_update'] = str(int(static_last_update))[-6:]


@app.template_filter('snake_to_title')
def snake_to_title(s):
    return " ".join([word.title() for word in s.split("_")])

@app.template_filter('env')
def env(default_value, key):
    # usage in template: {{ 'default_value' | env('KEY_NAME') }}
    return os.getenv(key, default_value)

@app.errorhandler(404)
def not_found(e):
    return render_template("404.html"), 404

@app.errorhandler(500)
def server_error(e):
    return render_template("500.html"), 500

if __name__ == '__main__':
    app.run(debug=True)

    # to run your local development server over SSL (recommened for finding content issues)
    # https://blog.filippo.io/mkcert-valid-https-certificates-for-localhost/
    # app.run(debug=True, ssl_context=(os.environ["LOCAL_SSL_CERT_PATH"], os.environ["LOCAL_SSL_KEY_PATH"]))