Source code for dedoc.metadata_extractors.concrete_metadata_extractors.base_metadata_extractor

from typing import Optional

from dedoc.metadata_extractors.abstract_metadata_extractor import AbstractMetadataExtractor


class BaseMetadataExtractor(AbstractMetadataExtractor):
    """
    This metadata extractor allows to extract metadata from the documents of any format.

    It returns the following information about the given file:
        - file name;
        - file name during parsing (unique);
        - file type (MIME);
        - file size in bytes;
        - time when the file was last accessed;
        - time when the file was created;
        - time when the file was last modified.
    """

    def can_extract(self,
                    file_path: str,
                    converted_filename: Optional[str] = None,
                    original_filename: Optional[str] = None,
                    parameters: Optional[dict] = None,
                    mime: Optional[str] = None,
                    extension: Optional[str] = None) -> bool:
        """
        This extractor can handle any file so the method always returns True.
        Look to the :meth:`~dedoc.metadata_extractors.AbstractMetadataExtractor.can_extract` documentation to get the information about parameters.
        """
        return True

    def extract(self,
                file_path: str,
                converted_filename: Optional[str] = None,
                original_filename: Optional[str] = None,
                parameters: Optional[dict] = None) -> dict:
        """
        Gets the basic meta-information about the file.
        Look to the :meth:`~dedoc.metadata_extractors.AbstractMetadataExtractor.extract` documentation to get the information about parameters.
        """
        from base64 import b64encode
        import os

        parameters = {} if parameters is None else parameters
        file_dir, file_name, converted_filename, original_filename = self._get_names(file_path, converted_filename, original_filename)
        meta_info = self._get_base_meta_information(file_dir, file_name, original_filename)

        if parameters.get("is_attached", False) and str(parameters.get("return_base64", "false")).lower() == "true":
            with open(os.path.join(file_dir, converted_filename), "rb") as file:
                meta_info["base64_encode"] = b64encode(file.read()).decode("utf-8")

        return meta_info

    @staticmethod
    def _get_base_meta_information(directory: str, filename: str, name_actual: str) -> dict:
        import os
        from dedoc.utils.utils import get_file_mime_type

        (mode, ino, dev, nlink, uid, gid, size, atime, mtime, ctime) = os.stat(os.path.join(directory, filename))
        meta = {
            "file_name": name_actual,
            "temporary_file_name": filename,
            "file_type": get_file_mime_type(os.path.join(directory, filename)),
            "size": size,  # in bytes
            "access_time": atime,
            "created_time": ctime,
            "modified_time": mtime
        }

        return meta