#!/usr/bin/env python
# coding: utf8
#
# Copyright (c) 2020 Centre National d'Etudes Spatiales (CNES).
#
# This file is part of CARS
# (see https://github.com/CNES/cars).
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
"""
This module contains class application factory.
"""
# Standard imports
import logging
from cars.applications.application_template import ScalingApplicationTemplate
# CARS imports
from cars.conf.input_parameters import ConfigType
[docs]
class Application:
"""
Application factory:
A class designed for registered all available Cars application and
instantiate when needed.
"""
# Dict (application_name:str, class: object) containing registered
# applications
available_applications = {}
def __new__(
cls,
app_name: str,
cfg: ConfigType = None,
scaling_coeff: float = 1,
):
"""
Return the instance of application associated with the application
name given as parameter
:param app_name: name of the application.
:type app_name: str
:param cfg: configuration {'matching_cost_method': value}
:type cfg: dictionary
:param scaling_coeff: scaling factor for resolution
:type scaling_coeff: float
"""
return cls.create_app(app_name, cfg, scaling_coeff)
[docs]
@classmethod
def create_app(cls, name: str, cfg: ConfigType, scaling_coeff: float = 1):
"""Factory command to create the application
Return the instance of application associated with the application
name given as parameter
:param app_name: name of the application.
:type app_name: str
:param cfg: configuration {'matching_cost_method': value}
:type cfg: dictionary
:param scaling_coeff: scaling factor for resolution
:type scaling_coeff: float
"""
try:
app_class = cls.available_applications[name]
except KeyError:
logging.error("No application named {0} supported".format(name))
return None
if issubclass(app_class, ScalingApplicationTemplate):
return app_class(scaling_coeff=scaling_coeff, conf=cfg)
return app_class(conf=cfg)
[docs]
@classmethod
def print_applications(cls):
"""
Print all registered applications
"""
for app_name in cls.available_applications:
print(app_name)
[docs]
@classmethod
def register(cls, app_name: str):
"""
Allows to register the application with its name
:param app_name: the application to be registered
:type app_name: string
"""
def decorator(app):
"""
Registers the class in the available methods
:param app: the app class to be registered
:type app: object
"""
cls.available_applications[app_name] = app
return app
return decorator