Hoping Virne to support multiple link/path attributes

[lin-yifan1]

I used virne to create a physical network and several virtual networks with both bandwidth and latency attributes, by modifying the yaml setting files. However, when I ran the program, I encountered the following error:

Traceback (most recent call last):
  File "/home/*/virne/main.py", line 25, in <module>
    run(config)
  File "/home/*/virne/main.py", line 13, in run
    scenario.run()
  File "/home/*/virne/virne/base/scenario.py", line 99, in run
    solution = self.solver.solve(instance)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/*/virne/virne/solver/heuristic/node_rank.py", line 45, in solve
    link_mapping_result = self.link_mapping(v_net, p_net, solution)
                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/*/virne/virne/solver/heuristic/node_rank.py", line 84, in link_mapping
    link_mapping_result = self.controller.link_mapping(v_net, p_net, solution=solution, 
                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/*/virne/virne/base/controller.py", line 812, in link_mapping
    return self.safely_link_mapping(v_net, p_net, solution, sorted_v_links, shortest_method, k, inplace)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/*/virne/virne/base/controller.py", line 845, in safely_link_mapping
    route_result, route_info = self.route(v_net, p_net, v_link, p_pair, solution, shortest_method=shortest_method, k=k)
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/*/virne/virne/base/controller.py", line 423, in route
    return self.safely_route(v_net, p_net, v_link, pl_pair, solution, shortest_method, k, rank_path_func)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/*/virne/virne/base/controller.py", line 459, in safely_route
    check_result, check_info = self.check_path_constraints(v_net, p_net, v_link, p_path)
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/*/virne/virne/base/controller.py", line 238, in check_path_constraints
    result, info = self.check_link_constraints(v_net, p_net, v_link, p_link)
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/*/virne/virne/base/controller.py", line 208, in check_link_constraints
    final_result, link_satisfiability_info = self.check_attributes(v_link, p_link, self.all_link_attrs)
                                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/*/virne/virne/base/controller.py", line 135, in check_attributes
    result, value = attr.check(v, p)
    ^^^^^^^^^^^^^
TypeError: cannot unpack non-iterable bool object

By examining the code I concluded that Virne does not support multiple link attributes or path constraints (e.g, latency) checking (I noticed the TODO sign in the check_path_constraints method). Hoping the new version of Virne will support these features.

---

Btw, 这个项目真的特别棒！VNE 领域的算法很多，但代码真的很少，希望大佬可以继续完善这个项目，感激不尽。

[GeminiLight]

Thanks! This feature has been in our update plans. Actually, latency constraints in VNE are complex due to multifaceted guarantees at various levels, including link-to-path and graph-to-graph. We intend to implement this feature as concisely and easily as possible. Please look forward to the update of the later version of Virne!