Source code for openlr_dereferencer.observer.abstract

"Contains the abstract observer class for the decoder"
from abc import abstractmethod
from typing import Sequence

from openlr import LocationReferencePoint

from ..decoding.candidate import Candidate
from ..maps import Line


class DecoderObserver:
    "Abstract class representing an observer to the OpenLR decoding process"

    @abstractmethod
    def on_candidates_found(self, lrp: LocationReferencePoint, candidates: Sequence[Candidate]):
        "Called by the decoder when it finds a list of candidates for a location reference point"

    @abstractmethod
    def on_route_success(self, from_lrp: LocationReferencePoint, to_lrp: LocationReferencePoint,
                         from_line: Line, to_line: Line, path: Sequence[Line]):
        """Called after the decoder successfully finds a route between two candidate
        lines for successive location reference points"""

    @abstractmethod
    def on_route_fail(self, from_lrp: LocationReferencePoint, to_lrp: LocationReferencePoint,
                      from_line: Line, to_line: Line):
        """Called after the decoder fails to find a route between two candidate
        lines for successive location reference points"""