Readers

Base class for all Readers

koheesio.pandas.readers.Reader

Base class for all Readers

A Reader is a Step that reads data from a source based on the input parameters and stores the result in self.output.df (DataFrame).

When implementing a Reader, the execute() method should be implemented. The execute() method should read from the source and store the result in self.output.df.

The Reader class implements a standard read() method that calls the execute() method and returns the result. This method can be used to read data from a Reader without having to call the execute() method directly. Read method does not need to be implemented in the child class.

The Reader class also implements a shorthand for accessing the output Dataframe through the df-property. If the output.df is None, .execute() will be run first.

execute abstractmethod

execute() -> Output

Execute on a Reader should handle self.output.df (output) as a minimum Read from whichever source -> store result in self.output.df

Source code in src/koheesio/pandas/readers/__init__.py

@abstractmethod
def execute(self) -> PandasStep.Output:
    """Execute on a Reader should handle self.output.df (output) as a minimum
    Read from whichever source -> store result in self.output.df
    """
    # self.output.df  # output dataframe
    ...