Loans API Documentation

Overview

This documentation outlines how to set up and use the Loans API, a Django backend designed for secure and efficient management of customer and loan data.

API Endpoints

The API is structured around the following endpoints:

Authentication

Obtain Token Pair: POST /api/token-auth/ - Obtain an access token pair.

Getting Started

Prerequisites

Python 3.10.0 or higher
Django 5.0.6 or higher
Django REST framework 3.15.1 or higher

Installation

Clone the repository:

git clone https://github.com/Sergioarg/loans_api.git

Navigate to the project directory:
```
cd users_api/
```
Create a virtual environment (optional but recommended):
```
python3 -m venv venv
```
Activate the virtual environment:
- On Windows:
```
.\venv\Scripts\activate
```
- On Unix or MacOS:
```
source venv/bin/activate
```
Install the required packages:
```
pip3 install -r requirements.txt
```
Apply migrations to set up the database:
```
python3 manage.py migrate
```

Create an admin user:

 python3 manage.py createsuperuser --username admin --email admin@example.com

Running the Server

To start the server, run:

python manage.py runserver

The server will start at http://localhost:8000.

API Endpoints

Usage

To interact with the API, you can use tools like curl, Postman, or any HTTP client library in your preferred programming language.

Endpoint: http://127.0.0.1:8000/api/token-auth/

Obtain API Token

Endpoint: /api/token-auth/
Method: POST

Body:

{
  "username": "exampleuser",
  "password": "examplepassword"
}

Response:
```
{
  "token": "API-TOKEN"
}
```

Accessing the API Endpoints

Once the application is running, you can access the API endpoints using a web browser or a tool like curl or Postman.

Curl Example:

  curl --location --request GET 'http://127.0.0.1:8000/api/customers/' \
  --header 'Content-Type: application/json' \
  --header 'Authorization: Token <YOUR_TOKEN>'

Customers Management

Table of methods

Endpoint	Method	Description	Response	Request Body	Parameters
/api/customers/	GET	Retrieves a list of all customers.	An array of `Customer` objects.	N/A	N/A
/api/customers/{id}/	GET	Retrieves a specific customer by their ID.	A `Customer` object or `404 Not Found` if the customer does not exist.	N/A	`id`: The ID of the customer.
/api/customers/{id}/balance	GET	Retrieves the balance of the customer by their ID.	Balance of the customer	N/A	`id`: The ID of the customer.
/api/customers/{id}/loans	GET	Retrieves the loans of the customer by their ID.	Array of loans	N/A	`id`: The ID of the customer.
/api/customers/{id}/payments	GET	Retrieves the payments of the customer by their ID.	Array of payments	N/A	`id`: The ID of the customer.
/api/customers/	POST	Creates a new customer.	`201 Created` with the created `Customer` object and the location of the new resource.	A `Customer` object.	N/A
/api/customers/{id}/	PUT	Updates an existing customer.	`204 No Content` if the update is successful, or `404 Not Found` if the customer does not exist.	A `Customer` object with the fields to update.	`id`: The ID of the customer to update.
/api/customers/{id}/	DELETE	Deletes a specific customer by their ID.	`200 OK` if the deletion is successful, or `404 Not Found` if the customer does not exist.	N/A	`id`: The ID of the customer to delete.

Endpoint: http://127.0.0.1:8000/api/customers/

Create a Customer

Endpoint: /api/customers/
Method: POST

Body:

{
  "score": 6000,
  "external_id": "customer_01"
}

Response:

{
  "score": "6000.00",
  "status": 1,
  "external_id": "customer_01",
  "preapproved_at": null
}

Loan Management

Endpoint: http://127.0.0.1:8000/api/loans/

Create a Loan

Endpoint: /api/loans/
Method: POST

Body:

{
  "amount": 4000,
  "external_id": "loan_01",
  "customer": 1
}

Response:

{
  "external_id": "loan_01",
  "amount": "4000.00",
  "status": 1,
  "outstanding": "4000.00",
  "customer_external_id": "customer_01"
}

Payment Management

Endpoint: http://127.0.0.1:8000/api/payments/

Create a Payment

Endpoint: /api/payments/
Method: POST

Body:

  {
    "total_amount": 2000,
    "external_id": "payment_01",
    "customer": 1,
    "payment_loan_detail": [
        {"loan": 1, "amount": 2000},
    ]
  }

Response:

{
  "total_amount": "2000",
  "status": 4,
  "paid_at": "2024-05-11T23:34:29.703632Z",
  "external_id": "payment_01",
  "customer_external_id": "customer_01",
  "loan_external_id": "loan_01",
  "payment_amount": 2000.0
}

Run Tests

Execute the Django test runner to run all tests in the project.

python3 manage.py test

Model ER

This is the ER diagram of the project.