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18dc62563c
* doc: add proxy README documentation * doc: edit general README files * add proxy code example Co-authored-by: Ruidy <r.nemausat@empfohlen.de>
28 lines
969 B
Python
28 lines
969 B
Python
from structural.proxy.real_subject import RealSubject
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from structural.proxy.subject import Subject
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class Proxy(Subject):
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"""The Proxy has an interface identical to the RealSubject."""
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def __init__(self, real_subject: RealSubject) -> None:
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self._real_subject = real_subject
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def request(self) -> None:
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"""
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The most common applications of the Proxy pattern are lazy loading,
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caching, controlling the access, logging, etc. A Proxy can perform one
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of these things and then, depending on the result, pass the execution to
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the same method in a linked RealSubject object.
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"""
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if self.check_access():
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self._real_subject.request()
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self.log_access()
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def check_access(self) -> bool:
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print("Proxy: Checking access prior to firing a real request.")
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return True
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def log_access(self) -> None:
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print("Proxy: Logging the time of request.", end="")
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