依赖注入中的其他数据

Question

我有如下代码：

class ISaver(abc.ABC):
    @abstractmethod
    def save(self, text):
        pass

class FileSaver(ISaver):
    def __init__(self, filepath):
        self.filepath = filepath  # <----- This part is important, please remember it

    def save(self, text):
        with open(self.filepath, 'w') as file:
            file.write(text)

class Scraper1:
    def __init__(self):
        self.file_saver = FileSaver('one.html')  # <----- And this

    def scrape(self, url):
        res = requests.get('https://example.com')
        self.file_saver.save(res.content)

class Scraper2:
    def __init__(self):
        self.file_saver = FileSaver('two.html')  # <----- And this

    def scrape(self, url):
        res = requests.get('https://anotherexample.com')
        self.file_saver.save(res.content)

现在，我想通过FileSaver将Scraper传递给python依赖注入器库。

结果应该是这样的：

class DIContainer(containers.DeclarativeContainer):
    file_saver = providers.Factory(FileSaver)  # <----- I don't want to pass the filepath here

class Scraper1:
    def __init__(self, file_saver = Provide[DIContainer.file_saver]):
        self.file_saver = file_saver  # <----- How should I pass the filepath here
    .
    .
    .

class Scraper2:
    def __init__(self, file_saver = Provide[DIContainer.file_saver]):
        self.file_saver = file_saver  # <----- Or here?
    .
    .
    .

我不能在我提到的行中编写filepath，因为它与项目场景相关。但我需要Scraper1和Scraper2中的这个变量。

有人能帮我解决这个问题吗？

Answer 1

你能有一个文件设置器并从Scraper1内部调用它吗？尽管这不再遵循DI模式；文件路径是Scraper1的依赖项，因此应该将其注入其中。

from dependency_injector import containers, providers
import abc

class ISaver(abc.ABC):
    @abc.abstractmethod
    def save(self, text):
        pass

class FileSaver(ISaver):
    def __init__(self):
        self.filepath = None

    def set_filepath(self, filepath):
        self.filepath = filepath

    def save(self, text):
        print(f"writing {text} to {self.filepath}")
        with open(self.filepath, 'w') as file:
            file.write(text)

class Scraper1:
    def __init__(self, file_saver):
        self.file_saver = file_saver
        self.file_saver.set_filepath('foo/bar')

class Container(containers.DeclarativeContainer):
    file_saver = providers.Factory(FileSaver)
    file_scraper = providers.Factory(Scraper1, file_saver)

if __name__ == "__main__":
    container = Container()
    container.wire(modules=[__name__])
    file_scraper = container.file_scraper()
    file_scraper.file_saver.save("hello")