All Questions

I have a probability study program that does 10,000,000 iterations. In each iteration you have to apply some heavy formulas that include the calculation of the factorial, and it is taking a long time.

I have been told that I must apply memorization to reduce process times.

Could you tell me what it is and how I use it?

How can you know if it is the first time the app is started?

It would be interesting, in the event that the user updates the application, it is detected as new or update.

I have a structure in HashMap and I need to iterate through a for. How can I do this iteration?

My code:

import java.util.HashMap;
import java.util.Map;

public class Testeo {
    public static void main(String[] args) {
        Map<Integer, String> datos = new HashMap<>();
        datos.put(1, "uno");
        datos.put(2, "dos");
        datos.put(3, "tres");

        //necesito iterar aquí
    }
}

I don't know if it's a recurring theme, that of knowing when to work with the Django authentication scheme, what is the best way to use it and extend it or if it is replaced by a custom one, but always with the idea of ​​preserving the mechanisms and functionalities of authentication.

Due to the above, I want to share this concern that I have about some probable alternatives or design approaches that I have thought about the following situation, with the hope that they can help me analyze/propose or choose the best one:

I am building an application where I have three different types of users:

• Medical
• Patient
• Physiotherapist

All three users must be able to log in to the system and there would be relationships (from the context of the business object of the application or requirements) between the Medical users with the patient users and the Physiotherapist users with the Patient users, understanding that:

• A patient is treated by a doctor
• A patient is treated by a therapist
• A patient could have these three roles in the system (I assume this would not be a problem)

My initial idea is to use Django's default authentication scheme (django.contrib.auth)

I initially thought of the following entity schema, in which the User model/table is equivalent to the auth_user table that Django automatically generates in our database when we apply our first migration, and in which Django users are stored:

In this User table I have three boolean fields that I have added which are: is_patient, is_medicalandis_physiotherapist

The previous one, I think it is an approach that would allow me to do what I am looking for, only that there is a detail and that is that Django's default authentication model cannot be modified, it is immutable, I would think that to modify it you would have to modify the core of Django and this is something more expensive or it would be necessary to do it well or to know what is being done.

is_patientFor this reason, the , is_medicaland fields is_physiotherapistcannot be added to the User table as I intend.

A classic recommendation that Django gives us in its documentation is to extend the User model with a OneToOne relationship to another model that contains the additional data that we want to add to the users. A basic example of what I say is this following figure:

This is how I can get the users I have in Django (managed by Django's default authentication scheme django.contrib.auth) to have additional attributes such as a photo, date of birth, among others that we want.

In relation to the latter, the scheme that I present below, could be useful to manage the different user roles that I need?, that is, patients, doctors and physiotherapists

I must have relationships between these tables:

• Medical Users and Patient Users
• Physiotherapist Users and Patient Users and so between them and other tables

With this approach, these relationships will not be affected?

The three different types of users, their attributes would be stored between the UserProfile and User tables.

In itself, the UserProfile table would have all the fields of the patient, doctor and therapist users.

Is this a good practice in terms of scalability? I know that they would not be normalized of course.

Because another alternative is to think about my initial approach, but without the boolean fields is_patient, is_medicaland is_physiotherapistthen by transitivity work with the different user roles, that is, like this:

In addition to the above, some alternatives are also presented such as:

1. Create a table/Model named Role

If I have a separate or independent role model/table, and this would be related to the Django User model then I could say that a User can have multiple roles. This approach can be useful if I want to store unique information about a particular role.

2. Django Permissions and Authorization System

Django Permissions and Authorization At the moment I don't know the degree of granularity (to what extent it would allow me to work with the models and their instances in terms of operations with them).

I have skimmed that the authorization and permissions system would allow me to work with the create, edit and delete operations

You could also look at the creation of groups, for example, a group called Doctors where medical users belong to it and that this group (and therefore the users that comprise it) can have certain permissions to certain models and operations. And so with the other types of users.

Is this another good alternative?

3. AUTH_USER_MODEL Creating a Custom User model

Another alternative that is presented for when Django's default user management scheme does not satisfy the requirements of user authentication or management in a project, is to replace or customize the user model, but I do not know if this would have its disadvantages in terms of not preserving the authentication mechanisms and more functionalities that Django provides us with its User model.

Does my requirement to have a patient user, a medical user and a physical therapist user require building a custom Users model?

Everything that Django shows us about managing users and the multiple things that they allow us to do with this theme is not something that is complicated in itself at first, but from what I have seen and from my point of view I dare to affirm that it is a somewhat extensive topic, and for the same reason, I feel somewhat confused to make the best decision according to what I need.

If anyone has done something similar or has any suggestions for guidance (I know it may be a very particular case to post it in a free community), I would be very grateful.

Thank you very much for your time and apologies for the long post.

POSTI need to make an API request to Googlethe URL:

https://www.google.com/recaptcha/api/siteverify?secret=ACA_LA_CLAVE&remoteip=IP&response=KEY_RESPONSE

I would like to do it without using a specific gem for that API GOOGLEbut as close to what Ruby2.2.0 brings by default, if possible.