def get_shortest_routes(route_db):
'''
Find all shortest routes for each prefix in routeDb
:param route_db: RouteDatabase
:return list of UnicastRoute of prefix & corresponding shortest nexthops
'''
shortest_routes = []
for route in sorted(route_db.routes,
key=lambda x: x.prefix.prefixAddress.addr):
if not route.paths:
continue
min_metric = min(route.paths, key=lambda x: x.metric).metric
nexthops = []
for path in route.paths:
if path.metric == min_metric:
nexthops.append(path.nextHop)
nexthops[-1].ifName = path.ifName
shortest_routes.append(ip_types.UnicastRoute(dest=route.prefix,
nexthops=nexthops))
return shortest_routes
def get_routes(self, route_db):
'''
Find all shortest routes for each prefix in routeDb
'''
shortest_routes = []
for route in sorted(route_db.routes):
if not route.paths:
continue
min_metric = min(route.paths, key=lambda x: x.metric).metric
nexthops = []
for path in route.paths:
if path.metric == min_metric:
nexthops.append(path.nextHop)
nexthops[-1].ifName = path.ifName
shortest_routes.append(
ip_types.UnicastRoute(dest=route.prefix, nexthops=nexthops))
return shortest_routes
def build_routes(prefixes, nexthops):
'''
:param prefixes: List of prefixes in string representation
:param nexthops: List of nexthops ip addresses in string presentation
:returns: list ip_types.UnicastRoute (structured routes)
:rtype: list
'''
prefixes = [utils.ip_str_to_prefix(p) for p in prefixes]
nhs = []
for nh_iface in nexthops:
iface, addr = None, None
# Nexthop may or may not be link-local. Handle it here well
if '@' in nh_iface:
addr, iface = nh_iface.split('@')
elif '%' in nh_iface:
addr, iface = nh_iface.split('%')
else:
addr = nh_iface
nexthop = utils.ip_str_to_addr(addr)
nexthop.ifName = iface
nhs.append(nexthop)
return [ip_types.UnicastRoute(dest=p, nexthops=nhs) for p in prefixes]
