Gain insights into clean architecture using Python. Delve into layered systems, design efficient applications, and integrate web components, error handling, and databases with test-driven development practices.

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Python Execution

Flask

Flask + Postgres

Python Test

Clean architecture is a software design methodology that separates the processes of an application into discrete steps instead of presenting them as “spaghetti code.” With the versatility of Python, software engineers can build performant, modular applications quickly using the Flask framework.

This course will help you build better applications using the principles of clean architecture. You’ll start with an introduction to data flow in clean systems and learn about the advantages of layered architectures. Next, you’ll learn system components and the connections between application layers. You’ll then design and build a clean system using Python by layering components in guided coding exercises. Finally, you’ll learn how to add functional components for the web, handle errors, and work with external databases using both Postgres and MongoDB. At each step, you’ll use test-driven development practices to ensure robust functionality.

Clean Architecture in Python

## The `Room` domain model

Let’s start with a simple definition of the `Room` domain model. As we mentioned before, clean architecture models are lighter than their counterparts in common web frameworks.


### Implementing test case for initialization
Following the **#key# TDD: Test-Driven Development #key# methodology**, the first thing we’ll write is the test. The test ensures that the model initializes with the correct values.

import uuid
from rentomatic.domain.room import Room

def test_room_model_init():
    code = uuid.uuid4()
    room = Room(
        code,
        size=200,
        price=10,
        longitude=-0.09998975,
        latitude=51.75436293,
    )

    assert room.code == code
    assert room.size == 200
    assert room.price == 10
    assert room.longitude == -0.09998975
    assert room.latitude == 51.75436293

Let’s make a note to create an empty file `__init__.py` in every subdirectory of `tests/` we create. In this case, we have the `tests/domain/__init__.py` file.

### Implement the `Room` domain model
Now let’s write the `Room` domain model to the file `rentomatic/domain/room.py`.


# The `Room` domain model

Let’s start with a simple definition of the `Room` domain model. As we mentioned before, clean architecture models are lighter than their counterparts in common web frameworks.


## Implementing test case for initialization
Following the **#key# TDD: Test-Driven Development #key# methodology**, the first thing we’ll write is the test. The test ensures that the model initializes with the correct values.

Let’s make a note to create an empty file `__init__.py` in every subdirectory of `tests/` we create. In this case, we have the `tests/domain/__init__.py` file.

## Implement the `Room` domain model
Now let’s write the `Room` domain model to the file `rentomatic/domain/room.py`.


Let’s learn about the importance of domain models in clean architecture.

Get Started

A Day in the Life of a Clean System

Components of Clean Architecture

A Simple Coding Example

Add a Web Application

Error Management

Integration with a Real External System Postgres

Integration with a Real External System MongoDB

Run a Production-ready System

Appendix

Domain Models

The `Room` domain model

Implementing test case for initialization

Domain Models

The Room domain model

Implementing test case for initialization

The `Room` domain model