mirror of
https://github.com/rjNemo/design-patterns
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27 lines
747 B
Python
27 lines
747 B
Python
from abc import abstractmethod
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from typing import Any, Optional
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from behavioral.chain_responsibility.handler import Handler
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class AbstractHandler(Handler):
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"""
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The default chaining behavior can be implemented inside a base handler
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class.
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"""
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_next_handler: Handler = None
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def set_next(self, handler: Handler) -> Handler:
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self._next_handler = handler
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# Returning a handler from here will let us link handlers in a
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# convenient way like this:
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# monkey.set_next(squirrel).set_next(dog)
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return handler
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@abstractmethod
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def handle(self, request: Any) -> Optional[str]:
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if self._next_handler:
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return self._next_handler.handle(request)
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return None
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