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 import logging
   7
   8
   9 DCDPID_BASE = 1000  # start of switch dpid's used for data center switches
  10
  11
  12 class EmulatorCompute(Docker):
  13     """
  14     Emulator specific compute node class.
  15     Inherits from Dockernet's Docker host class.
  16     Represents a single container connected to a (logical)
  17     data center.
  18     We can add emulator specific helper functions to it.
  19     """
  20
  21     def __init__(
  22             self, name, dimage, **kwargs):
  23         logging.debug("Create EmulatorCompute instance: %s" % name)
  24         self.datacenter = None  # pointer to current DC
  25
  26         # call original Docker.__init__
  27         Docker.__init__(self, name, dimage, **kwargs)
  28
  29     def getNetworkStatus(self):
  30         """
  31         Helper method to receive information about the virtual networks
  32         this compute instance is connected to.
  33         """
  34         # format list of tuples (name, Ip, MAC, isUp, status)
  35         return [(str(i), i.IP(), i.MAC(), i.isUp(), i.status())
  36                 for i in self.intfList()]
  37
  38     def getStatus(self):
  39         """
  40         Helper method to receive information about this compute instance.
  41         """
  42         status = {}
  43         status["name"] = self.name
  44         status["network"] = self.getNetworkStatus()
  45         status["image"] = self.dimage
  46         status["cpu_quota"] = self.cpu_quota
  47         status["cpu_period"] = self.cpu_period
  48         status["cpu_shares"] = self.cpu_shares
  49         status["cpuset"] = self.cpuset
  50         status["mem_limit"] = self.mem_limit
  51         status["memswap_limit"] = self.memswap_limit
  52         status["state"] = self.dcli.inspect_container(self.dc)["State"]
  53         status["id"] = self.dcli.inspect_container(self.dc)["Id"]
  54         status["datacenter"] = (None if self.datacenter is None
  55                                 else self.datacenter.label)
  56         return status
  57
  58
  59 class Datacenter(object):
  60     """
  61     Represents a logical data center to which compute resources
  62     (Docker containers) can be added at runtime.
  63
  64     Will also implement resource bookkeeping in later versions.
  65     """
  66
  67     DC_COUNTER = 1
  68
  69     def __init__(self, label):
  70         self.net = None  # DCNetwork to which we belong
  71         # each node (DC) has a short internal name used by Mininet
  72         # this is caused by Mininets naming limitations for swtiches etc.
  73         self.name = "dc%d" % Datacenter.DC_COUNTER
  74         Datacenter.DC_COUNTER += 1
  75         self.label = label  # use this for user defined names
  76         self.switch = None  # first prototype assumes one "bigswitch" per DC
  77         self.containers = {}  # keep track of running containers
  78
  79     def _get_next_dc_dpid(self):
  80         global DCDPID_BASE
  81         DCDPID_BASE += 1
  82         return DCDPID_BASE
  83
  84     def create(self):
  85         """
  86         Each data center is represented by a single switch to which
  87         compute resources can be connected at run time.
  88
  89         TODO: This will be changed in the future to support multiple networks
  90         per data center
  91         """
  92         self.switch = self.net.addSwitch(
  93             "%s.s1" % self.name, dpid=hex(self._get_next_dc_dpid())[2:])
  94         logging.debug("created data center switch: %s" % str(self.switch))
  95
  96     def start(self):
  97         pass
  98
  99     def startCompute(self, name, image=None, network=None):
 100         """
 101         Create a new container as compute resource and connect it to this
 102         data center.
 103
 104         TODO: This interface will change to support multiple networks to which
 105         a single container can be connected.
 106         """
 107         assert name is not None
 108         # no duplications
 109         if name in [c.name for c in self.net.getAllContainers()]:
 110             raise Exception("Container with name %s already exists." % name)
 111         # set default parameter
 112         if image is None:
 113             image = "ubuntu"
 114         if network is None:
 115             network = {}  # {"ip": "10.0.0.254/8"}
 116         # create the container and connect it to the given network
 117         d = self.net.addDocker("%s" % (name), dimage=image)
 118         self.net.addLink(d, self.switch, params1=network)
 119         # do bookkeeping
 120         self.containers[name] = d
 121         d.datacenter = self
 122         return d  # we might use UUIDs for naming later on
 123
 124     def stopCompute(self, name):
 125         """
 126         Stop and remove a container from this data center.
 127         """
 128         assert name is not None
 129         if name not in self.containers:
 130             raise Exception("Container with name %s not found." % name)
 131         self.net.removeLink(
 132             link=None, node1=self.containers[name], node2=self.switch)
 133         self.net.removeDocker("%s" % (name))
 134         del self.containers[name]
 135         return True
 136
 137     def listCompute(self):
 138         """
 139         Return a list of all running containers assigned to this
 140         data center.
 141         """
 142         return list(self.containers.itervalues())
 143
 144     def getStatus(self):
 145         """
 146         Return a dict with status information about this DC.
 147         """
 148         return {"label": self.label}