Initializes cross origin resource sharing for the application in Flask-Cors

.env

CORS_ORIGINS=
CORS_METHODS=
CORS_ALLOW_HEADERS=
CORS_EXPOSE_HEADERS=
CORS_SUPPORTS_CREDENTIALS=
CORS_MAX_AGE=

run.py

# https://flask-cors.corydolphin.com/en/latest/api.html

CORS(
    app=app, 
    resources = app.config['CORS_RESOURCES'],
    origins = app.config['CORS_ORIGINS'],
    methods = app.config['CORS_METHODS'],
    allow_headers = app.config['CORS_ALLOW_HEADERS'],
    expose_headers = app.config['CORS_EXPOSE_HEADERS'],
    supports_credentials = app.config['CORS_SUPPORTS_CREDENTIALS'],
    max_age = app.config['CORS_MAX_AGE']
)

@app.after_request
def after_request(response):
    response.headers.add(
        'Access-Control-Allow-Headers', app.config['CORS_ALLOW_HEADERS']
    )
    return response