Source code for bexchange.backend

# Copyright (C) 2021- Swedish Meteorological and Hydrological Institute (SMHI)
#
# This file is part of baltrad-exchange.
#
# baltrad-exchange is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# baltrad-exchange is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
# See the GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with baltrad-exchange.  If not, see <http://www.gnu.org/licenses/>.
###############################################################################

## Abstract backend

## @file
## @author Anders Henja, SMHI
## @date 2021-08-18

from abc import abstractmethod, ABCMeta

import pkg_resources

from bexchange.util import abstractclassmethod

from bexchange import config



class DuplicateEntry(Exception):
    """thrown to indicate that an entry already exists
    """




class IntegrityError(RuntimeError):
    """thrown to indicate a conflict between resources
    """
    pass




class Backend(object):
    """Backend interface
    """
    __metaclass__ = ABCMeta



    @abstractmethod
    def store_file(self, path, nodename):
        """store a file in the database
        :param path: path to the file
        :type path: string
        :param nodename: The origin that tries to store the file
        """
        raise NotImplementedError()




    @abstractmethod
    def post_message(self, json_message, node_name):
        """ensures that a posted message arrives to interested parties
        :param json_message: The json message
        :type path: string
        :param nodename: The origin that sent the message
        """
        raise NotImplementedError()





    @abstractmethod
    def metadata_from_file(self, path):
        """Parses a file and returns the metadata for this file.
        :param path: path to the file
        :type path: string
        :return the metadata for this file
        """
        raise NotImplementedError()

    


    @abstractmethod
    def get_storage_manager(self):
        """Returns the storage manager
        :return the storage manager
        """
        raise NotImplementedError()    

    


    @abstractmethod
    def get_auth_manager(self):
        """Returns the auth manager
        :return the auth manager
        """
        raise NotImplementedError()    




    @abstractmethod
    def get_tmp_folder(self):
        """Returns the global temporary folder name if defined
        :return the temporary folder name
        """
        raise NotImplementedError()