Implement OAuth Authentication (GitHub & Google) and Email/Password Login, Registration Page and Login Page

[Rajshah1302]

Description

This PR introduces GitHub OAuth, Google OAuth, and email/password authentication methods across both the frontend and backend.

Frontend:

• Created a login page with options for GitHub OAuth, Google OAuth, and email/password login.
• Integrated GitHub and Google OAuth login flows in the frontend, including token handling and user details display after successful login.
• Added error handling for invalid login credentials and empty fields in the email/password login form.

Backend:

• Implemented the GitHub OAuth authentication API to handle user login via GitHub, including token exchange and user info retrieval from GitHub.
• Implemented the Google OAuth authentication API to handle user login via Google, with token exchange and user info retrieval from Google.
• Created email/password login and registration APIs, including password hashing, email validation, and error handling for missing or incorrect credentials.
• Updated the user model to store GitHub ID, Google ID, and password.

Database:

• Modified the user schema to support OAuth credentials (GitHub and Google), in addition to email/password authentication.
• Ensured secure password storage using bcrypt hashing.

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Related Issue

#108

Motivation and Context

This change introduces multiple authentication options to make the application more flexible and secure. By adding OAuth integrations for GitHub and Google alongside the traditional email/password login, users can authenticate via their preferred method. This enhances user experience and makes the application more accessible.

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Screenshots (In case of UI changes):

• Login Page
  

• Registration Page:
  

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Types of changes

• New feature (non-breaking change which adds functionality)

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Checklist:

• My code follows the code style of this project.
• All new and existing tests have passed and it does not give any unexpected errors.

[Rajshah1302]

Demo

Webiu.mp4

[Rajshah1302]

@rajutkarsh07 Please review this PR

[Rajshah1302]

ENV File Format

To get Google OAuth working, you'll need to generate an mkcert as Google OAuth allows only HTTPS requests.
Here's the .env file setup for the server:

PORT=5100
MONGODB_URI=
JWT_SECRET=
GITHUB_ACCESS_TOKEN=
# Google OAuth
GOOGLE_CLIENT_ID=
GOOGLE_CLIENT_SECRET=
GOOGLE_REDIRECT_URI=

# GitHub OAuth
GITHUB_CLIENT_ID=
GITHUB_CLIENT_SECRET=
GITHUB_REDIRECT_URI=

SSL_KEY_PATH=
SSL_CERT_PATH=