Login with CPF with Nodejs, Reactjs and Mongodb

Question

Well I built an API for registrations in the remote mongodb database (Atlas), I can register, the intention is to offer a form for the user data(Name, Cpf, phone) and then do the CPF, made the login the user should be directed to a page (Dashboard) with the user name and its data. In Insomnia, I pick up Cpf via req.body {"cpf":"241545444"} and it works, returns my user with that Cpf, because I used user.findOne({req.body.cpf}) to filter the first user with that CPF:

The problem is when I try to make that data appear on the frontend with Reactjs, I used Axios to request the Api, I set up the Login dialog, and ask to return the user data based on the input data (Cpf), I store this data in State and Setstate but this data is not compared with that of the api and returns a requeste.data null...

How do I get the inout Cpf to compare to the one in the api and returns an object as shown in Inuit ???

Answer 1

Good night, Matthew, good night! From what you described, the most I can answer without having the details of the browser debug error is the following: Cors is missing from your Backend, because by default Backend does not respond to requests for a domain not allowed, so when you try to make a request for Axios in Front-end, it returns NULL. Cors is a specification that allows you (owner of your Backend) to tell them which domains (i.e., which Front-ends) can consume data from your API. If this is really the error, if you can log that appears in the Console, you could confirm this hypothesis.

Here a Link teaching how to add Cors to your Node and Express Backend if this is really the problem