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