[FEAT]: Send email enpoint

[EmmanuelOmoiya]

Description

Endpoint to send mail to customer or user.

Acceptance Criteria

• The endpoint should be accesible at /api/v1/mails/send.

• The endpoint should accept HTTP POST requests.

• The endpoint should be secured to ensure that only a user with an admin role.

• Proper authentication mechanisms (e.g. JWT, OAuth2) should be implemented.

• Requests to the endpoint must include a valid authentication token in the Authorization header. Authorization: Bearer <token>

• Request body

  {
      "template": "login-successful",
      "recipient": "[email protected]",
      "params": {
          "first_name": "Emmanuel",
          "last_name": "Omoiya",
          "ip_address": "10.43.54.263"
      }
  }

• Response (Success)

  {
     "status_code": "200",
     "message": "Mail sending request accepted and is being proccessed",
     "error": "",
  }

• Response (Error)

  {
      "status_code": 401,
      "message": "Unauthorized",
      "error": "Bad Request"
  }

  Invalid params

  {
      "status_code": 400,
      "message": "Invalid params, 'user_name' not found'",
      "error": "Bad Request"
  }

  Internal Server Error

  {
      "status_code": 500,
      "message": "Internal server error",
      "error": "Bad Request"
  }

Purpose

To send mail using a template to a customer / user.

Requirements

• User must be authenticated thereby having a Authoirization: Bearer <token> header in the request body
• User must have the role of an admin
• User account must be active

Expected Outcome

• A response with status_code of 200 and message of "Mail sending request accepted and is being proccessed"

Testing

1. Unit Tests
   The system should have unit tests covering:

• Ensure the request body has the right properties and the value are of the right type
• Test that the appropriate response and status code is returned