Synnefo

import logging

from socket import getfqdn

from functools import wraps

from django import dispatch

from django.db import transaction

from django.utils import simplejson as json

from snf_django.lib.api import faults

from django.conf import settings

from synnefo import quotas

from synnefo.api import util

from synnefo.logic import backend

from synnefo.logic.backend_allocator import BackendAllocator

from synnefo.db.models import (NetworkInterface, VirtualMachine, Network,

                               VirtualMachineMetadata, FloatingIP)

from vncauthproxy.client import request_forwarding as request_vnc_forwarding

log = logging.getLogger(__name__)

# server creation signal

server_created = dispatch.Signal(providing_args=["created_vm_params"])

def validate_server_action(vm, action):

    if vm.deleted:

        raise faults.BadRequest("Server '%s' has been deleted." % vm.id)

    # Destroyin a server should always be permitted

    if action == "DESTROY":

        return

    # Check that there is no pending action

    pending_action = vm.task

    if pending_action:

        if pending_action == "BUILD":

            raise faults.BuildInProgress("Server '%s' is being build." % vm.id)

        raise faults.BadRequest("Can not perform '%s' action while there is a"

                                " pending '%s'." % (action, pending_action))

    # Check if action can be performed to VM's operstate

    operstate = vm.operstate

    if operstate == "BUILD" and action != "BUILD":

        raise faults.BuildInProgress("Server '%s' is being build." % vm.id)

    elif (action == "START" and operstate != "STOPPED") or\

         (action == "STOP" and operstate != "STARTED") or\

         (action == "RESIZE" and operstate != "STOPPED") or\

         (action in ["CONNECT", "DISCONNECT"] and operstate != "STOPPED"

          and not settings.GANETI_USE_HOTPLUG):

        raise faults.BadRequest("Can not perform '%s' action while server is"

                                " in '%s' state." % (action, operstate))

    return

def server_command(action):

    """Handle execution of a server action.

    Helper function to validate and execute a server action, handle quota

    commission and update the 'task' of the VM in the DB.

    1) Check if action can be performed. If it can, then there must be no

       pending task (with the exception of DESTROY).

    2) Handle previous commission if unresolved:

       * If it is not pending and it to accept, then accept

       * If it is not pending and to reject or is pending then reject it. Since

       the action can be performed only if there is no pending task, then there

       can be no pending commission. The exception is DESTROY, but in this case

       the commission can safely be rejected, and the dispatcher will generate

       the correct ones!

    3) Issue new commission and associate it with the VM. Also clear the task.

    4) Send job to ganeti

    5) Update task and commit

    """

    def decorator(func):

        @wraps(func)

        @transaction.commit_on_success

        def wrapper(vm, *args, **kwargs):

            user_id = vm.userid

            validate_server_action(vm, action)

            vm.action = action

            commission_name = "client: api, resource: %s" % vm

            quotas.handle_resource_commission(vm, action=action,

                                              commission_name=commission_name)

            vm.save()

            # XXX: Special case for server creation!

            if action == "BUILD":

                # Perform a commit, because the VirtualMachine must be saved to

                # DB before the OP_INSTANCE_CREATE job in enqueued in Ganeti.

                # Otherwise, messages will arrive from snf-dispatcher about

                # this instance, before the VM is stored in DB.

                transaction.commit()

                # After committing the locks are released. Refetch the instance

                # to guarantee x-lock.

                vm = VirtualMachine.objects.select_for_update().get(id=vm.id)

            # Send the job to Ganeti and get the associated jobID

            try:

                job_id = func(vm, *args, **kwargs)

            except Exception as e:

                if vm.serial is not None:

                    # Since the job never reached Ganeti, reject the commission

                    log.debug("Rejecting commission: '%s', could not perform"

                              " action '%s': %s" % (vm.serial,  action, e))

                    transaction.rollback()

                    quotas.reject_serial(vm.serial)

                    transaction.commit()

                raise

            if action == "BUILD" and vm.serial is not None:

                # XXX: Special case for server creation: we must accept the

                # commission because the VM has been stored in DB. Also, if

                # communication with Ganeti fails, the job will never reach

                # Ganeti, and the commission will never be resolved.

                quotas.accept_serial(vm.serial)

            log.info("user: %s, vm: %s, action: %s, job_id: %s, serial: %s",

                     user_id, vm.id, action, job_id, vm.serial)

            # store the new task in the VM

            if job_id is not None:

                vm.task = action

                vm.task_job_id = job_id

            vm.save()

            return vm

        return wrapper

    return decorator

@transaction.commit_on_success

def create(userid, name, password, flavor, image, metadata={},

           personality=[], private_networks=None, floating_ips=None,

           use_backend=None):

    if use_backend is None:

        # Allocate server to a Ganeti backend

        use_backend = allocate_new_server(userid, flavor)

    if private_networks is None:

        private_networks = []

    if floating_ips is None:

        floating_ips = []

    # Fix flavor for archipelago

    disk_template, provider = util.get_flavor_provider(flavor)

    if provider:

        flavor.disk_template = disk_template

        flavor.disk_provider = provider

        flavor.disk_origin = None

        if provider == 'vlmc':

            flavor.disk_origin = image['checksum']

            image['backend_id'] = 'null'

    else:

        flavor.disk_provider = None

    # We must save the VM instance now, so that it gets a valid

    # vm.backend_vm_id.

    vm = VirtualMachine.objects.create(name=name,

                                       backend=use_backend,

                                       userid=userid,

                                       imageid=image["id"],

                                       flavor=flavor,

                                       operstate="BUILD")

    log.info("Created entry in DB for VM '%s'", vm)

    nics = create_instance_nics(vm, userid, private_networks, floating_ips)

    for key, val in metadata.items():

        VirtualMachineMetadata.objects.create(

            meta_key=key,

            meta_value=val,

            vm=vm)

    # Create the server in Ganeti.

    vm = create_server(vm, nics, flavor, image, personality, password)

    return vm

@transaction.commit_on_success

def allocate_new_server(userid, flavor):

    """Allocate a new server to a Ganeti backend.

    Allocation is performed based on the owner of the server and the specified

    flavor. Also, backends that do not have a public IPv4 address are excluded

    from server allocation.

    This function runs inside a transaction, because after allocating the

    instance a commit must be performed in order to release all locks.

    """

    backend_allocator = BackendAllocator()

    use_backend = backend_allocator.allocate(userid, flavor)

    if use_backend is None:

        log.error("No available backend for VM with flavor %s", flavor)

        raise faults.ServiceUnavailable("No available backends")

    return use_backend

@server_command("BUILD")

def create_server(vm, nics, flavor, image, personality, password):

    # dispatch server created signal needed to trigger the 'vmapi', which

    # enriches the vm object with the 'config_url' attribute which must be

    # passed to the Ganeti job.

    server_created.send(sender=vm, created_vm_params={

        'img_id': image['backend_id'],

        'img_passwd': password,

        'img_format': str(image['format']),

        'img_personality': json.dumps(personality),

        'img_properties': json.dumps(image['metadata']),

    })

    # send job to Ganeti

    try:

        jobID = backend.create_instance(vm, nics, flavor, image)

    except:

        log.exception("Failed create instance '%s'", vm)

        jobID = None

        vm.operstate = "ERROR"

        vm.backendlogmsg = "Failed to send job to Ganeti."

        vm.save()

        vm.nics.all().update(state="ERROR")

    # At this point the job is enqueued in the Ganeti backend

    vm.backendjobid = jobID

    vm.save()

    log.info("User %s created VM %s, NICs %s, Backend %s, JobID %s",

             vm.userid, vm, nics, backend, str(jobID))

    return jobID

def create_instance_nics(vm, userid, private_networks=[], floating_ips=[]):

    """Create NICs for VirtualMachine.

    Helper function for allocating IP addresses and creating NICs in the DB

    for a VirtualMachine. Created NICs are the combination of the default

    network policy (defined by administration settings) and the private

    networks defined by the user.

    """

    attachments = []

    for network_id in settings.DEFAULT_INSTANCE_NETWORKS:

        network, address = None, None

        if network_id == "SNF:ANY_PUBLIC":

            network, address = util.allocate_public_address(backend=vm.backend)

        else:

            try:

                network = Network.objects.get(id=network_id, deleted=False)

            except Network.DoesNotExist:

                msg = "Invalid configuration. Setting"\

                      " 'DEFAULT_INSTANCE_NETWORKS' contains invalid"\

                      " network '%s'" % network_id

                log.error(msg)

                raise Exception(msg)

            if network.subnet is not None and network.dhcp:

                address = util.get_network_free_address(network)

        attachments.append((network, address))

    for address in floating_ips:

        floating_ip = add_floating_ip_to_vm(vm=vm, address=address)

        network = floating_ip.network

        attachments.append((network, address))

    for network_id in private_networks:

        network, address = None, None

        network = util.get_network(network_id, userid, non_deleted=True)

        if network.public:

            raise faults.Forbidden("Can not connect to public network")

        if network.dhcp:

            address = util.get_network_free_address(network)

        attachments.append((network, address))

    nics = []

    for index, (network, address) in enumerate(attachments):

        # Create VM's public NIC. Do not wait notification form ganeti

        # hooks to create this NIC, because if the hooks never run (e.g.

        # building error) the VM's public IP address will never be

        # released!

        nic = NetworkInterface.objects.create(machine=vm, network=network,

                                              index=index, ipv4=address,

                                              state="BUILDING")

        nics.append(nic)

    return nics

@server_command("DESTROY")

def destroy(vm):

    log.info("Deleting VM %s", vm)

    return backend.delete_instance(vm)

@server_command("START")

def start(vm):

    log.info("Starting VM %s", vm)

    return backend.startup_instance(vm)

@server_command("STOP")

def stop(vm):

    log.info("Stopping VM %s", vm)

    return backend.shutdown_instance(vm)

@server_command("REBOOT")

def reboot(vm, reboot_type):

    if reboot_type not in ("SOFT", "HARD"):

        raise faults.BadRequest("Malformed request. Invalid reboot"

                                " type %s" % reboot_type)

    log.info("Rebooting VM %s. Type %s", vm, reboot_type)

    return backend.reboot_instance(vm, reboot_type.lower())

@server_command("RESIZE")

def resize(vm, flavor):

    old_flavor = vm.flavor

    # User requested the same flavor

    if old_flavor.id == flavor.id:

        raise faults.BadRequest("Server '%s' flavor is already '%s'."

                                % (vm, flavor))

        return None

    # Check that resize can be performed

    if old_flavor.disk != flavor.disk:

        raise faults.BadRequest("Can not resize instance disk.")

    if old_flavor.disk_template != flavor.disk_template:

        raise faults.BadRequest("Can not change instance disk template.")

    log.info("Resizing VM from flavor '%s' to '%s", old_flavor, flavor)

    commission_info = {"cyclades.cpu": flavor.cpu - old_flavor.cpu,

                       "cyclades.ram": 1048576 * (flavor.ram - old_flavor.ram)}

    # Save serial to VM, since it is needed by server_command decorator

    vm.serial = quotas.issue_commission(user=vm.userid,

                                        source=quotas.DEFAULT_SOURCE,

                                        provisions=commission_info,

                                        name="resource: %s. resize" % vm)

    return backend.resize_instance(vm, vcpus=flavor.cpu, memory=flavor.ram)

@server_command("SET_FIREWALL_PROFILE")

def set_firewall_profile(vm, profile, index=0):

    log.info("Setting VM %s, NIC index %s, firewall %s", vm, index, profile)

    if profile not in [x[0] for x in NetworkInterface.FIREWALL_PROFILES]:

        raise faults.BadRequest("Unsupported firewall profile")

    backend.set_firewall_profile(vm, profile=profile, index=index)

    return None

@server_command("CONNECT")

def connect(vm, network):

    if network.state != 'ACTIVE':

        raise faults.BuildInProgress('Network not active yet')

    address = None

    if network.subnet is not None and network.dhcp:

        # Get a free IP from the address pool.

        address = util.get_network_free_address(network)

    log.info("Connecting VM %s to Network %s(%s)", vm, network, address)

    nic = NetworkInterface.objects.create(machine=vm,

                                          network=network,

                                          ipv4=address,

                                          state="BUILDING")

    return backend.connect_to_network(vm, nic)

@server_command("DISCONNECT")

def disconnect(vm, nic_index):

    nic = util.get_nic_from_index(vm, nic_index)

    log.info("Removing NIC %s from VM %s", str(nic.index), vm)

    if nic.dirty:

        raise faults.BuildInProgress('Machine is busy.')

    else:

        vm.nics.all().update(dirty=True)

    return backend.disconnect_from_network(vm, nic)

def console(vm, console_type):

    """Arrange for an OOB console of the specified type

    This method arranges for an OOB console of the specified type.

    Only consoles of type "vnc" are supported for now.

    It uses a running instance of vncauthproxy to setup proper

    VNC forwarding with a random password, then returns the necessary

    VNC connection info to the caller.

    """

    log.info("Get console  VM %s, type %s", vm, console_type)

    # Use RAPI to get VNC console information for this instance

    if vm.operstate != "STARTED":

        raise faults.BadRequest('Server not in ACTIVE state.')

    if settings.TEST:

        console_data = {'kind': 'vnc', 'host': 'ganeti_node', 'port': 1000}

    else:

        console_data = backend.get_instance_console(vm)

    if console_data['kind'] != 'vnc':

        message = 'got console of kind %s, not "vnc"' % console_data['kind']

        raise faults.ServiceUnavailable(message)

    # Let vncauthproxy decide on the source port.

    # The alternative: static allocation, e.g.

    # sport = console_data['port'] - 1000

    sport = 0

    daddr = console_data['host']

    dport = console_data['port']

    password = util.random_password()

    if settings.TEST:

        fwd = {'source_port': 1234, 'status': 'OK'}

    else:

        fwd = request_vnc_forwarding(sport, daddr, dport, password)

    if fwd['status'] != "OK":

        raise faults.ServiceUnavailable('vncauthproxy returned error status')

    # Verify that the VNC server settings haven't changed

    if not settings.TEST:

        if console_data != backend.get_instance_console(vm):

            raise faults.ServiceUnavailable('VNC Server settings changed.')

    console = {

        'type': 'vnc',

        'host': getfqdn(),

        'port': fwd['source_port'],

        'password': password}

    return console

@server_command("CONNECT")

def add_floating_ip(vm, address):

    floating_ip = add_floating_ip_to_vm(vm, address)

    nic = NetworkInterface.objects.create(machine=vm,

                                          network=floating_ip.network,

                                          ipv4=floating_ip.ipv4,

                                          state="BUILDING")

    log.info("Connecting VM %s to floating IP %s. NIC: %s", vm, floating_ip,

             nic)

    return backend.connect_to_network(vm, nic)

def add_floating_ip_to_vm(vm, address):

    """Get a floating IP by it's address and add it to VirtualMachine.

    Helper function for looking up a FloatingIP by it's address and associating

    it with a VirtualMachine object (without adding the NIC in the Ganeti

    backend!). This function also checks if the floating IP is currently used

    by any instance and if it is available in the Backend that hosts the VM.

    """

    user_id = vm.userid

    try:

        # Get lock in VM, to guarantee that floating IP will only by assigned

        # once

        floating_ip = FloatingIP.objects.select_for_update()\

                                        .get(userid=user_id, ipv4=address,

                                             deleted=False)

    except FloatingIP.DoesNotExist:

        raise faults.ItemNotFound("Floating IP '%s' does not exist" % address)

    if floating_ip.in_use():

        raise faults.Conflict("Floating IP '%s' already in use" %

                              floating_ip.id)

    bnet = floating_ip.network.backend_networks.filter(backend=vm.backend_id)

    if not bnet.exists():

        msg = "Network '%s' is a floating IP pool, but it not connected"\

              " to backend '%s'" % (floating_ip.network, vm.backend)

        raise faults.ServiceUnavailable(msg)

    floating_ip.machine = vm

    floating_ip.save()

    return floating_ip

@server_command("DISCONNECT")

def remove_floating_ip(vm, address):

    user_id = vm.userid

    try:

        floating_ip = FloatingIP.objects.select_for_update()\

                                        .get(userid=user_id, ipv4=address,

                                             deleted=False, machine=vm)

    except FloatingIP.DoesNotExist:

        raise faults.ItemNotFound("Floating IP '%s' does not exist" % address)

    try:

        nic = NetworkInterface.objects.get(machine=vm, ipv4=address)

    except NetworkInterface.DoesNotExist:

        raise faults.ItemNotFound("Floating IP '%s' is not attached to"

                                  "VM '%s'" % (floating_ip, vm))

    log.info("Removing NIC %s from VM %s. Floating IP '%s'", str(nic.index),

             vm, floating_ip)

    return backend.disconnect_from_network(vm, nic)

def rename(server, new_name):

    """Rename a VirtualMachine."""

    old_name = server.name

    server.name = new_name

    server.save()

    log.info("Renamed server '%s' from '%s' to '%s'", server, old_name,

             new_name)

    return server