routinglib.py 文件源码

def generateRoutes(baseRange, numRoutes, subnetSize=None):
    baseNetwork = ip_network(baseRange)

    # We need to get at least 2 addresses out of each subnet, so the biggest
    # prefix length we can have is /30
    maxPrefixLength = baseNetwork.max_prefixlen - 2

    if subnetSize is not None:
        return list(baseNetwork.subnets(new_prefix=subnetSize))

    trySubnetSize = baseNetwork.prefixlen + 1
    while trySubnetSize <= maxPrefixLength and \
            len(list(baseNetwork.subnets(new_prefix=trySubnetSize))) < numRoutes:
        trySubnetSize += 1

    if trySubnetSize > maxPrefixLength:
        raise Exception("Can't get enough routes from input parameters")

    return list(baseNetwork.subnets(new_prefix=trySubnetSize))[:numRoutes]