apps/pci/optimizers/solver/optimizer.py

   1 # -------------------------------------------------------------------------
   2 #   Copyright (c) 2018 AT&T Intellectual Property
   3 #   Copyright (C) 2020 Wipro Limited.
   4 #
   5 #   Licensed under the Apache License, Version 2.0 (the "License");
   6 #   you may not use this file except in compliance with the License.
   7 #   You may obtain a copy of the License at
   8 #
   9 #       http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 #   Unless required by applicable law or agreed to in writing, software
  12 #   distributed under the License is distributed on an "AS IS" BASIS,
  13 #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 #   See the License for the specific language governing permissions and
  15 #   limitations under the License.
  16 #
  17 # -------------------------------------------------------------------------
  18 #
  19
  20 from collections import defaultdict
  21 import itertools
  22 import os
  23 import pymzn
  24
  25 from apps.pci.optimizers.solver.ml_model import MlModel
  26 from apps.pci.optimizers.solver.pci_utils import get_id
  27 from apps.pci.optimizers.solver.pci_utils import mapping
  28 from osdf.config.base import osdf_config
  29
  30 BASE_DIR = os.path.dirname(__file__)
  31 cell_id_mapping = dict()
  32 id_cell_mapping = dict()
  33
  34
  35 def pci_optimize(network_cell_info, cell_info_list, request_json):
  36     global cell_id_mapping, id_cell_mapping
  37     cell_id_mapping, id_cell_mapping = mapping(network_cell_info)
  38     original_pcis = get_original_pci_list(network_cell_info)
  39     unchangeable_pcis = get_ids_of_fixed_pci_cells(request_json['cellInfo'].get('fixedPCICells', []))
  40     neighbor_edges = get_neighbor_list(network_cell_info)
  41     second_level_edges = get_second_level_neighbor(network_cell_info)
  42     ignorable_links = get_ignorable_links(network_cell_info, request_json)
  43     anr_flag = is_anr(request_json)
  44
  45     dzn_data = build_dzn_data(cell_info_list, ignorable_links, neighbor_edges, second_level_edges, anr_flag,
  46                               original_pcis, unchangeable_pcis)
  47
  48     ml_enabled = osdf_config.core['PCI']['ml_enabled']
  49     if ml_enabled:
  50         MlModel().get_additional_inputs(dzn_data, network_cell_info)
  51
  52     return build_pci_solution(dzn_data, ignorable_links, anr_flag)
  53
  54
  55 def get_ids_of_fixed_pci_cells(fixed_pci_list):
  56     fixed_pci_ids = set()
  57     for cell in fixed_pci_list:
  58         fixed_pci_ids.add(cell_id_mapping[cell])
  59     return fixed_pci_ids
  60
  61
  62 def get_cell_id_pci_mapping(network_cell_info):
  63     original_pcis = dict()
  64     for cell in network_cell_info['cell_list']:
  65         for nbr in cell['nbr_list']:
  66             if cell_id_mapping[nbr['targetCellId']] not in original_pcis:
  67                 original_pcis[cell_id_mapping[nbr['targetCellId']]] = nbr['pciValue']
  68     return original_pcis
  69
  70
  71 def get_original_pci_list(network_cell_info):
  72     cell_id_pci_mapping = get_cell_id_pci_mapping(network_cell_info)
  73     original_pcis_list = []
  74     for i in range(len(cell_id_pci_mapping)):
  75         original_pcis_list.append(cell_id_pci_mapping.get(i))
  76     return original_pcis_list
  77
  78
  79 def build_pci_solution(dzn_data, ignorable_links, anr_flag):
  80     mzn_solution = solve(get_mzn_model(anr_flag), dzn_data)
  81     if mzn_solution == 'UNSATISFIABLE':
  82         return mzn_solution
  83     solution = {'pci': mzn_solution[0]['pci']}
  84
  85     if anr_flag:
  86         removables = defaultdict(list)
  87         used_ignorables = mzn_solution[0]['used_ignorables']
  88         index = 0
  89         for i in ignorable_links:
  90             if used_ignorables[index] > 0:
  91                 removables[i[0]].append(i[1])
  92             index += 1
  93         solution['removables'] = removables
  94     return solution
  95
  96
  97 def build_dzn_data(cell_info_list, ignorable_links, neighbor_edges, second_level_edges, anr_flag, original_pcis,
  98                    unchangeable_pcis):
  99     dzn_data = {
 100         'NUM_NODES': len(cell_info_list),
 101         'NUM_PCIS': len(cell_info_list),
 102         'NUM_NEIGHBORS': len(neighbor_edges),
 103         'NEIGHBORS': get_list(neighbor_edges),
 104         'NUM_SECOND_LEVEL_NEIGHBORS': len(second_level_edges),
 105         'SECOND_LEVEL_NEIGHBORS': get_list(second_level_edges),
 106         'PCI_UNCHANGEABLE_CELLS': unchangeable_pcis,
 107         'ORIGINAL_PCIS': original_pcis
 108     }
 109     if anr_flag:
 110         dzn_data['NUM_IGNORABLE_NEIGHBOR_LINKS'] = len(ignorable_links)
 111         dzn_data['IGNORABLE_NEIGHBOR_LINKS'] = get_list(ignorable_links)
 112     return dzn_data
 113
 114
 115 def get_mzn_model(anr_flag):
 116     if anr_flag:
 117         mzn_model = os.path.join(BASE_DIR, 'min_confusion_inl.mzn')
 118     else:
 119         mzn_model = os.path.join(BASE_DIR, 'no_conflicts_no_confusion.mzn')
 120     return mzn_model
 121
 122
 123 def is_anr(request_json):
 124     return 'pci-anr' in request_json["requestInfo"]["optimizers"]
 125
 126
 127 def get_list(edge_list):
 128     array_list = []
 129     for s in edge_list:
 130         array_list.append([s[0], s[1]])
 131     return sorted(array_list)
 132
 133
 134 def solve(mzn_model, dzn_data):
 135     return pymzn.minizinc(mzn=mzn_model, data=dzn_data)
 136
 137
 138 def get_neighbor_list(network_cell_info):
 139     neighbor_list = set()
 140     for cell in network_cell_info['cell_list']:
 141         add_to_neighbor_list(network_cell_info, cell, neighbor_list)
 142     return neighbor_list
 143
 144
 145 def add_to_neighbor_list(network_cell_info, cell, neighbor_list):
 146     for nbr in cell.get('nbr_list', []):
 147         host_id = cell['id']
 148         nbr_id = get_id(network_cell_info, nbr['targetCellId'])
 149         if nbr_id and host_id != nbr_id:
 150             neighbor_list.add((host_id, nbr_id))
 151
 152
 153 def get_second_level_neighbor(network_cell_info):
 154     second_neighbor_list = set()
 155     for cell in network_cell_info['cell_list']:
 156         comb_list = build_second_level_list(network_cell_info, cell)
 157         for comb in comb_list:
 158             if comb[0] and comb[1]:
 159                 second_neighbor_list.add((comb[0], comb[1]))
 160     return sorted(second_neighbor_list)
 161
 162
 163 def build_second_level_list(network_cell_info, cell):
 164     second_nbr_list = []
 165     for nbr in cell.get('nbr_list', []):
 166         second_nbr_list.append(get_id(network_cell_info, nbr['targetCellId']))
 167     return [list(elem) for elem in list(itertools.combinations(second_nbr_list, 2))]
 168
 169
 170 def get_ignorable_links(network_cell_info, request_json):
 171     ignorable_list = set()
 172     anr_input_list = request_json["cellInfo"].get('anrInputList', [])
 173     if anr_input_list:
 174         for anr_info in anr_input_list:
 175             cell_id = get_id(network_cell_info, anr_info['cellId'])
 176             anr_removable = anr_info.get('removeableNeighbors', [])
 177             for anr in anr_removable:
 178                 ignorable_list.add((cell_id, get_id(network_cell_info, anr)))
 179     return ignorable_list