builder_pattern.py

class NetworkService:
    def __init__(self, url: str = "", auth: str = "", cache: int = 0):
        self.components = {}

        if url:
            self.components["URL"] = url
        if auth:
            self.components["Authorization"] = auth
        if cache:
            self.components["Cache-Control"] = cache

    def show(self):
        print(self.components)


if __name__ == "__main__":

    service1 = NetworkService(url="google.com")
    service1.show()

    service2 = NetworkService(url="youtube.com", auth="abc123", cache=60000)
    service2.show()

# you have the option to create different versions of the same class as instance.
# Its not mandatory for all the objects to be added here

# class NetworkService:
#     def __init__(self):
#         self.components = {}

#     def add(self, key: str, value: str):
#         self.components[key] = value

#     def show(self):
#         print(self.components)


# class NetworkServiceBuilder:
#     def __init__(self):
#         self._service = NetworkService()

#     def add_target_url(self, url: str):
#         self._service.add("URL", url)

#     def add_auth(self, auth: str):
#         self._service.add("Authorization", auth)

#     def add_caching(self, cache: int):
#         self._service.add("Cache-Control", cache)

#     def build(self) -> NetworkService:
#         service = self._service
#         self._service = NetworkService()
#         return service


# if __name__ == "__main__":
#     builder = NetworkServiceBuilder()
#     builder.add_target_url("google.com")

#     service1 = builder.build()
#     service1.show()

#     builder.add_target_url("youtube")
#     builder.add_auth("abc123")
#     builder.add_caching(60000)

#     service2 = builder.build()
#     service2.show()