src/emuvim/dcemulator/node.py

   1 """
   2 Distributed Cloud Emulator (dcemulator)
   3 (c) 2015 by Manuel Peuster <manuel.peuster@upb.de>
   4 """
   5 from mininet.node import Docker
   6 from mininet.link import Link
   7 from emuvim.dcemulator.resourcemodel import NotEnoughResourcesAvailable
   8 import logging
   9 import time
  10 import json
  11
  12 LOG = logging.getLogger("dcemulator")
  13 LOG.setLevel(logging.DEBUG)
  14
  15
  16 DCDPID_BASE = 1000  # start of switch dpid's used for data center switches
  17
  18
  19 class EmulatorCompute(Docker):
  20     """
  21     Emulator specific compute node class.
  22     Inherits from Dockernet's Docker host class.
  23     Represents a single container connected to a (logical)
  24     data center.
  25     We can add emulator specific helper functions to it.
  26     """
  27
  28     def __init__(
  29             self, name, dimage, **kwargs):
  30         self.datacenter = kwargs.get("datacenter")  # pointer to current DC
  31         self.flavor_name = kwargs.get("flavor_name")
  32         LOG.debug("Starting compute instance %r in data center %r" % (name, str(self.datacenter)))
  33         # call original Docker.__init__
  34         Docker.__init__(self, name, dimage, **kwargs)
  35
  36     def getNetworkStatus(self):
  37         """
  38         Helper method to receive information about the virtual networks
  39         this compute instance is connected to.
  40         """
  41         # format list of tuples (name, Ip, MAC, isUp, status)
  42         return [(str(i), i.IP(), i.MAC(), i.isUp(), i.status())
  43                 for i in self.intfList()]
  44
  45     def getStatus(self):
  46         """
  47         Helper method to receive information about this compute instance.
  48         """
  49         status = {}
  50         status["name"] = self.name
  51         status["network"] = self.getNetworkStatus()
  52         status["image"] = self.dimage
  53         status["flavor_name"] = self.flavor_name
  54         status["cpu_quota"] = self.cpu_quota
  55         status["cpu_period"] = self.cpu_period
  56         status["cpu_shares"] = self.cpu_shares
  57         status["cpuset"] = self.cpuset
  58         status["mem_limit"] = self.mem_limit
  59         status["memswap_limit"] = self.memswap_limit
  60         status["state"] = self.dcli.inspect_container(self.dc)["State"]
  61         status["id"] = self.dcli.inspect_container(self.dc)["Id"]
  62         status["datacenter"] = (None if self.datacenter is None
  63                                 else self.datacenter.label)
  64         return status
  65
  66
  67 class Datacenter(object):
  68     """
  69     Represents a logical data center to which compute resources
  70     (Docker containers) can be added at runtime.
  71
  72     Will also implement resource bookkeeping in later versions.
  73     """
  74
  75     DC_COUNTER = 1
  76
  77     def __init__(self, label, metadata={}, resource_log_path=None):
  78         self.net = None  # DCNetwork to which we belong
  79         # each node (DC) has a short internal name used by Mininet
  80         # this is caused by Mininets naming limitations for swtiches etc.
  81         self.name = "dc%d" % Datacenter.DC_COUNTER
  82         Datacenter.DC_COUNTER += 1
  83         # use this for user defined names that can be longer than self.name
  84         self.label = label
  85         # dict to store arbitrary metadata (e.g. latitude and longitude)
  86         self.metadata = metadata
  87         # path to which resource information should be logged (e.g. for experiments). None = no logging
  88         self.resource_log_path = resource_log_path
  89         # first prototype assumes one "bigswitch" per DC
  90         self.switch = None
  91         # keep track of running containers
  92         self.containers = {}
  93         # pointer to assigned resource model
  94         self._resource_model = None
  95
  96     def __repr__(self):
  97         return self.label
  98
  99     def _get_next_dc_dpid(self):
 100         global DCDPID_BASE
 101         DCDPID_BASE += 1
 102         return DCDPID_BASE
 103
 104     def create(self):
 105         """
 106         Each data center is represented by a single switch to which
 107         compute resources can be connected at run time.
 108
 109         TODO: This will be changed in the future to support multiple networks
 110         per data center
 111         """
 112         self.switch = self.net.addSwitch(
 113             "%s.s1" % self.name, dpid=hex(self._get_next_dc_dpid())[2:])
 114         LOG.debug("created data center switch: %s" % str(self.switch))
 115
 116     def start(self):
 117         pass
 118
 119     def startCompute(self, name, image=None, command=None, network=None, flavor_name="tiny"):
 120         """
 121         Create a new container as compute resource and connect it to this
 122         data center.
 123         :param name: name (string)
 124         :param image: image name (string)
 125         :param command: command (string)
 126         :param network: networks list({"ip": "10.0.0.254/8"}, {"ip": "11.0.0.254/24"})
 127         :param flavor_name: name of the flavor for this compute container
 128         :return:
 129         """
 130         assert name is not None
 131         # no duplications
 132         if name in [c.name for c in self.net.getAllContainers()]:
 133             raise Exception("Container with name %s already exists." % name)
 134         # set default parameter
 135         if image is None:
 136             image = "ubuntu:trusty"
 137         if network is None:
 138             network = {}  # {"ip": "10.0.0.254/8"}
 139         if isinstance(network, dict):
 140             network = [network]  # if we have only one network, put it in a list
 141         if isinstance(network, list):
 142             if len(network) < 1:
 143                 network.append({})
 144
 145         # create the container
 146         d = self.net.addDocker(
 147             "%s" % (name),
 148             dimage=image,
 149             dcmd=command,
 150             datacenter=self,
 151             flavor_name=flavor_name
 152         )
 153
 154         # apply resource limits to container if a resource model is defined
 155         if self._resource_model is not None:
 156             try:
 157                 self._resource_model.allocate(d)
 158                 self._resource_model.write_allocation_log(d, self.resource_log_path)
 159             except NotEnoughResourcesAvailable as ex:
 160                 LOG.warning("Allocation of container %r was blocked by resource model." % name)
 161                 LOG.info(ex.message)
 162                 # ensure that we remove the container
 163                 self.net.removeDocker(name)
 164                 return None
 165
 166         # connect all given networks
 167         # if no --net option is given, network = [{}], so 1 empty dict in the list
 168         # this results in 1 default interface with a default ip address
 169         for nw in network:
 170             # TODO we cannot use TCLink here (see: https://github.com/mpeuster/dockernet/issues/3)
 171             self.net.addLink(d, self.switch, params1=nw, cls=Link)
 172         # do bookkeeping
 173         self.containers[name] = d
 174         return d  # we might use UUIDs for naming later on
 175
 176     def stopCompute(self, name):
 177         """
 178         Stop and remove a container from this data center.
 179         """
 180         assert name is not None
 181         if name not in self.containers:
 182             raise Exception("Container with name %s not found." % name)
 183         LOG.debug("Stopping compute instance %r in data center %r" % (name, str(self)))
 184
 185         # call resource model and free resources
 186         if self._resource_model is not None:
 187             self._resource_model.free(self.containers[name])
 188             self._resource_model.write_free_log(self.containers[name], self.resource_log_path)
 189
 190         # remove links
 191         self.net.removeLink(
 192             link=None, node1=self.containers[name], node2=self.switch)
 193
 194         # remove container
 195         self.net.removeDocker("%s" % (name))
 196         del self.containers[name]
 197
 198         return True
 199
 200     def listCompute(self):
 201         """
 202         Return a list of all running containers assigned to this
 203         data center.
 204         """
 205         return list(self.containers.itervalues())
 206
 207     def getStatus(self):
 208         """
 209         Return a dict with status information about this DC.
 210         """
 211         return {
 212             "label": self.label,
 213             "internalname": self.name,
 214             "switch": self.switch.name,
 215             "n_running_containers": len(self.containers),
 216             "metadata": self.metadata
 217         }
 218
 219     def assignResourceModel(self, rm):
 220         """
 221         Assign a resource model to this DC.
 222         :param rm: a BaseResourceModel object
 223         :return:
 224         """
 225         if self._resource_model is not None:
 226             raise Exception("There is already an resource model assigned to this DC.")
 227         self._resource_model = rm
 228         self.net.rm_registrar.register(self, rm)
 229         LOG.info("Assigned RM: %r to DC: %r" % (rm, self))
 230