model.py

#!/usr/bin/env python3

import logging
from json import load

logging.basicConfig(level=logging.DEBUG,
                    format='%(asctime)s [%(levelname)s] %(message)s')
log = logging.getLogger('model')


class ClientModel(object):
    def __init__(self, definition_file='lwm2m-object-definitions.json', data_file='data.json'):
        with open(definition_file) as f:
            self.definition = load(f)
        with open(data_file) as f:
            self.data = load(f)
        # simple validation: check if all data objects are in the definition
        for obj in self.objects():
            if not self.has_definition(obj):
                exit(f'{data_file} contains undefined object with ID {obj}. Aborting.')

    def objects(self):
        return [x for x in sorted([int(i) for i in self.data.keys()])]

    def instances(self, obj):
        _insts = self.data[str(obj)]
        return [x for x in sorted([int(i) for i in _insts.keys()])]

    def resources(self, obj, inst=0):
        return [x for x in sorted([int(i) for i in self.data[str(obj)][str(inst)].keys()])]

    def resource(self, obj, inst, res):
        return self.data[str(obj)][str(inst)][str(res)]

    def has_definition(self, obj):
        return str(obj) in self.definition.keys()

    def is_object_multi_instance(self, obj):
        return self.definition[str(obj)]['instancetype'] == 'multiple'

    def is_resource_multi_instance(self, obj, inst, res):
        return self.definition[str(obj)]['resourcedefs'][str(res)]['instancetype'] == 'multiple'

    def resource_iter(self):
        for obj in self.objects():
            for inst in self.instances(obj):
                for res in self.resources(obj, inst):
                    yield (str(obj), str(inst), str(res))

    def instance_iter(self):
        for obj in self.objects():
            for inst in self.instances(obj):
                yield (str(obj), str(inst))

    def get_object_links(self):
        for obj in self.objects():
            for inst in self.instances(obj):
                yield f'</{obj}/{inst}>'

    def is_path_valid(self, path):
        if len(path) == 3:
            _obj = int(path[0])
            _inst = int(path[1])
            _res = int(path[2])
            return _obj in self.objects() and _inst in self.instances(_obj) and _res in self.resources(_obj, _inst)
        elif len(path) == 2:
            _obj = int(path[0])
            _inst = int(path[1])
            return _obj in self.objects() and _inst in self.instances(_obj)
        elif len(path) == 1:
            _obj = int(path[0])
            return _obj in self.objects()
        else:
            raise AttributeError(f'invalid path length: {len(path)}')

    def is_resource_readable(self, obj, inst, res):
        _ops = self.definition[obj]['resourcedefs'][str(res)]['operations']
        return False if _ops == 'NONE' else 'R' in _ops

    def is_resource_executable(self, obj, inst, res):
        _ops = self.definition[obj]['resourcedefs'][str(res)]['operations']
        return False if _ops == 'NONE' else 'E' in _ops

    def set_resource(self, obj, inst, res, content):
        self.data[str(obj)][str(inst)][str(res)] = content

    def apply(self, data):
        for obj in data.keys():
            for inst in data[obj].keys():
                for res in data[obj][inst].keys():
                    log.debug(
                        f'applying {obj}/{inst}/{res} = {data[obj][inst][res]}')
                    self.set_resource(obj, inst, res, data[obj][inst][res])


if __name__ == '__main__':
    model = ClientModel()
    log.debug(f'object links: {",".join(model.get_object_links())}')
    log.debug(f'objects: {model.objects()}')
    for obj in model.objects():
        log.debug(
            f'object {obj} is multi-instance: {model.is_object_multi_instance(obj)}')
        log.debug(f'instances for object {obj}: {model.instances(obj)}')
        for inst in model.instances(obj):
            log.debug(
                f'resources for /{obj}/{inst}: {model.resources(obj, inst)}')
            log.debug(
                '===============================================================================================')
            for res in model.resources(obj, inst):
                log.debug(
                    f'resource /{obj}/{inst}/{res} is multi-instance: {model.is_resource_multi_instance(obj, inst, res)}')
                log.debug(
                    f'resource /{obj}/{inst}/{res}: "{model.resource(obj, inst, res)}"')
            log.debug(
                '===============================================================================================')