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