bug fix due to tx_osnr add

tx_osnr was impacting automatic mode selection feature : this commit solves the error
+ add a novel version of the excel example with an empty mode cases

Signed-off-by: EstherLerouzic <esther.lerouzic@orange.com>

examples/meshTopologyExampleV2_services.json

@@ -10,7 +10,7 @@
         "te-bandwidth": {
           "technology": "flexi-grid",
           "trx_type": "Voyager",
-          "trx_mode": "mode 1",
+          "trx_mode": null,
           "effective-freq-slot": [
             {
               "n": "null",
@@ -45,7 +45,7 @@
             }
           ],
           "spacing": 50000000000.0,
-          "max-nb-of-channel": 80,
+          "max-nb-of-channel": null,
           "output-power": 0.0012589254117941673,
           "path_bandwidth": 0
         }
@@ -133,8 +133,8 @@
             }
           ],
           "spacing": 50000000000.0,
-          "max-nb-of-channel": 80,
+          "max-nb-of-channel": null,
-          "output-power": 0.0012589254117941673,
+          "output-power": null,
           "path_bandwidth": 60000000000.0
         }
       },
@@ -152,7 +152,7 @@
         "te-bandwidth": {
           "technology": "flexi-grid",
           "trx_type": "vendorA_trx-type1",
-          "trx_mode": "mode 2",
+          "trx_mode": null,
           "effective-freq-slot": [
             {
               "n": "null",
@@ -160,8 +160,8 @@
             }
           ],
           "spacing": 75000000000.0,
-          "max-nb-of-channel": 63,
+          "max-nb-of-channel": null,
-          "output-power": 0.0019952623149688794,
+          "output-power": null,
           "path_bandwidth": 150000000000.0
         }
       },
@@ -188,7 +188,7 @@
           ],
           "spacing": 75000000000.0,
           "max-nb-of-channel": 63,
-          "output-power": 0.0019952623149688794,
+          "output-power": null,
           "path_bandwidth": 20000000000.0
         }
       },

examples/path_requests_run.py

@@ -69,6 +69,7 @@ def requests_from_json(json_data,equipment):
         # nb_channel is computed based on min max frequency and spacing
         trx_params = trx_mode_params(equipment,params['trx_type'],params['trx_mode'],True)
         params.update(trx_params)
+        print(trx_params['tx_osnr'])
         # optical power might be set differently in the request. if it is indicated then the 
         # params['power'] is updated
         if req['path-constraints']['te-bandwidth']['output-power']:
@@ -208,6 +209,7 @@ def compute_path_with_disjunction(network, equipment, pathreqlist, pathlist):
                     pathreq.tsp_mode = mode['format']
                     pathreq.format = mode['format']
                     pathreq.OSNR = mode['OSNR']
+                    pathreq.tx_osnr = mode['tx_osnr']
                     pathreq.bit_rate = mode['bit_rate']
                 else :
                     total_path = []

gnpy/core/equipment.py

@@ -173,6 +173,7 @@ def trx_mode_params(equipment, trx_type_variety='', trx_mode='', error_message=F
                        "OSNR": None,
                        "bit_rate": None,
                        "roll_off": None,
+                       "tx_osnr":None,
                        "cost":None}
         trx_params = {**mode_params}
         trx_params['frequency'] = equipment['Transceiver'][trx_type_variety].frequency

gnpy/core/request.py

@@ -410,22 +410,26 @@ def propagate_and_optimize_mode(path, req, equipment, show=False):
                 if m['baud_rate'] == b]
             modes_to_explore = sorted(modes_to_explore, 
                 key = lambda x: x['bit_rate'], reverse=True)
+            print(modes_to_explore)
             # step2 : computes propagation for each baudrate: stop and select the first that passes
             found_a_feasible_mode = False
             # TODO : the case of roll of is not included: for now use SI one
             # TODO : if the loop in mode optimization does not have a feasible path, then bugs
+            for m in modes_to_explore :
                 si = create_input_spectral_information(
                 req.frequency['min'], equipment['SI']['default'].roll_off,
-            b, req.power, req.spacing, req.nb_channel, req.tx_osnr)
+                b, req.power, req.spacing, req.nb_channel, m['tx_osnr'])
                 for el in path:
                     si = el(si)
                 if show :
                     print(el)
-            for m in modes_to_explore :
+                if path[-1].snr is not None:
                     if round(mean(path[-1].snr+lin2db(b/(12.5e9))),2) > m['OSNR'] :
                         found_a_feasible_mode = True
                         return path, m
-        # only get to this point if no budrate/mode staisfies OSNR requirement
+                else:  
+                    return [], None
+        # only get to this point if no baudrate/mode satisfies OSNR requirement
         # returns the last propagated path and mode
         msg = f'Warning! Request {req.request_id}: no mode satisfies path SNR requirement.\n'
         print(msg)