Source code for caspia.gateway.network

import hashlib
from copy import deepcopy

import caspia.meadow
import caspia.node
from caspia.gateway.cidmanagement import CidManagement


class Network:
    """ Manages Caspia CAN Network """
    def __init__(self, pollen_client, cidmng: CidManagement):
        self.pollen_client = pollen_client
        self.cidmng = cidmng
        self.nodes = dict()
        self._component_cache = dict()

    def get_node(self, name):
        """ Return node for a given name.
            Create a new one, if it does not exist yet.
        """
        if name in self.nodes:
            return self.nodes[name]
        cid = self.cidmng.lease(name)
        node = caspia.node.Node(self.pollen_client, cid)
        self.nodes[name] = node
        return node

    def reset_configuration(self):
        self._component_cache = dict()

    def get_configured_component(self, node, comp_cls, comp_cfg):
        """ Return existing or a new Component instance
            configured based on given config
        """
        # We have to make a deep copy of the config, because it will contain
        # rules-specific configuration, which has to be cleared on reset_configuration().
        comp_cfg = deepcopy(comp_cfg)
        cfg_hash = self._get_config_hash(node, comp_cfg)
        if cfg_hash in self._component_cache:
            return self._component_cache[cfg_hash]
        else:
            _, comp = node.register_component(comp_cls)
            comp.config = comp_cfg
            self._component_cache[cfg_hash] = comp
            return comp

    def _get_config_hash(self, node, comp_cfg):
        hsh = hashlib.sha1(comp_cfg.get_bytes())
        hsh.update(int.to_bytes(node.can_id, 3, 'little'))
        return hsh.hexdigest()