Do Dash apps reload all data upon client log in?
The only thing that is called on every page load is the function you can assign to app.layout. This is useful if you want to display dynamic content like the current date on your page.
Everything else is just executed once when the app is starting. 
This means if you load your data outside the app.layout (which I assume is the case) everything is loaded just once.
I'm wondering about how a dash app works in terms of loading data, parsing and doing initial calcs when serving to a client who logs onto the website.
For instance, my app initially loads a bunch of static local csv data, parses a bunch of dates and loads them into a few pandas data frames. This data is then displayed on a map for the client.
Does the app have to reload/parse all of this data every time a client logs onto the website? Or does the dash server load all the data only the first time it is instantiated and then just dish it out every time a client logs on?
If the data reloads every time, I would then use quick parsers like udatetime, but if not, id prefer to use a convenient parser like pendulum which isn't as efficient (but wouldn't matter if it only parses once).
I hope that question makes sense. Thanks in advance!