Simple Blazor app to register an email address with a password

THIS REPOSITORY IS ARCHIVED

Description

The frontend app requires the user to enter a valid email and a password that is strong enough (8 characters long minimum and contains letters, numbers and symbols). It also requires the user to retype the password to reduce the possiblity of mistyping.

Email validity is checked using EmailValidation. Password strength is checked using PasswordValidator.

When all validation checks are completed, the 'Register' button is enabled. When the user presses this button, the following happens:

1. The email address is checked against the backend service to verify it isn't already found in the database. If it is, the user is notified
2. Next, the password is encrypted using BCrypt.Net-Core before sending a POST request to the backend server
3. Lastly, the form is cleared and a message is shown to the user of whether the registration was a success or not

The backend service and database

The backend service consists of single controller called Users that provides a GET endpoint to check for an existing email address and POST endpoint for adding a new email/password combination.

The database is implemented using SQLite and is created at launch if not present. All SQL scripts for creating the Users table, querying for users and inserting new ones are attached as embedded resources to the backend DLL.

Requirements and instructions to build

This project is built using and depends on:

• .NET 6 SDK
• Various NuGet packages mentioned above for providing email and password checks and password encryption
• Xunit and NSubstitute for unit and integration tests

How to run

• Clone this repository to your machine
• Make sure you have .NET 6 SDK installed
• If you have Visual Studio on your machine, open the solution file and mark both Backend and Fronted solutions as startup projects, then rebuild and run
• You can also use dotnet CLI tool to run the project. In this mode, Run Backend.csproj and Frontend.csproj on their own terminals

Caveat! Make sure ports 5000 and 5001 are free on your machine, otherwise one or both apps fail to launch

Tests

Both projects contain unit tests for the service classes the "business logic" is implemented in. Furthermore, BackendIntegrationTests verify that the SQLite database can be setup and used properly without having to just run the project and hope for the best.

Limitations

• All network traffic flows unencrypted via plain HTTP. Dealing with certificate errors and exceptions seemed too much for this so I decided not to enable HTTPS
• Blazor is a new ASP.NET technology for quickly building interactive web UIs. As it's so new, it's bound to have some limitations that prevent production use at this stage but for a tech demo / interview homework it seemed like a good tool
• I didn't code any UI tests for this as the register form is quite simple and easily testable manually

Potential improvements

• Both projects could be Dockerized and deployed to a Kubernetes cluster with an ingress controller setup. This way the apps themselves can remain using unencrypted HTTP for communication between them within the closed cluster and the ingress controller would take care of allowing only HTTPS to the frontend from internet.
• Email verification mechanism for newly registered accounts
• DatabaseService could be split into two services, like a base service that offers generic DB operations. That would definitely be good to do if this project would require more than one DB connection but I decided go with KISS principle here since abstraction just for the sake of abstraction isn't healthy :)