Node.js API with SOLID principles

API for a gym chek-in app.

Functional Requirements

• Should be able to sign up;
• Should be able to sign in;
• Should be able to fetch the profile of a authenticated user;
• Should be able to fetch the number of check-ins of a user;
• Should be able to obtain the check-in history of the user;
• Should be possible to search gyms nearby;
• Should be possible to search gyms by name;
• Should be possible to check-in in a gym;
• Should be possible to validate a user's check-in;
• Should be possible to add a gym;

Business rules

• The user shouldn't be able to sign up with a duplicated e-mail;
• The user cannot check-in twice in the same day;
• The user cannot check-in if they aren't near (100m) a gym;
• Check-in can be validated up to 20 minutes after being created;
• Check-in can only be validated by admins;
• Gyms can only be added by admins;

Non-functional requirements

• User password must be encrypted;
• All the data must be persisted in a PostgresSQL database;
• All data lists must be paginated with 20 items per page;
• User mus be identified by a JWT.