Method from_filename

awscli/s3transfer/utils.py:470–506

Convenience factory function to create from a filename. :type start_byte: int :param start_byte: The first byte from which to start reading. :type chunk_size: int :param chunk_size: The max chunk size to read. Trying to read pass the end of the chunk si

(
        cls,
        filename,
        start_byte,
        chunk_size,
        callbacks=None,
        enable_callbacks=True,
    )

    @classmethod
    def from_filename(
        cls,
        filename,
        start_byte,
        chunk_size,
        callbacks=None,
        enable_callbacks=True,
    ):
        """Convenience factory function to create from a filename.

        :type start_byte: int
        :param start_byte: The first byte from which to start reading.

        :type chunk_size: int
        :param chunk_size: The max chunk size to read.  Trying to read
            pass the end of the chunk size will behave like you've
            reached the end of the file.

        :type full_file_size: int
        :param full_file_size: The entire content length associated
            with ``fileobj``.

        :type callbacks: function(amount_read)
        :param callbacks: Called whenever data is read from this object.

        :type enable_callbacks: bool
        :param enable_callbacks: Indicate whether to invoke callback
            during read() calls.

        :rtype: ``ReadFileChunk``
        :return: A new instance of ``ReadFileChunk``

        """
        f = open(filename, 'rb')
        f.seek(start_byte)
        file_size = os.fstat(f.fileno()).st_size
        return cls(f, chunk_size, file_size, callbacks, enable_callbacks)

    def _calculate_file_size(
        self, fileobj, requested_size, start_byte, actual_file_size