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 synnefo 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.logic.rapi import GanetiApiError

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

                               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":

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

    elif (action == "START" and operstate == "STARTED") or\

         (action == "STOP" and operstate == "STOPPED") or\

         (action == "RESIZE" and operstate == "STARTED"):

        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)

            # Resolve(reject) previous serial if it is still pending!!

            previous_serial = vm.serial

            if previous_serial and not previous_serial.resolved:

                quotas.resolve_vm_commission(serial=previous_serial)

            # Check if action is quotable and issue the corresponding

            # commission

            serial = None

            commission_info = quotas.get_commission_info(vm, action=action)

            if commission_info is not None:

                # Issue new commission, associate it with the VM

                serial = quotas.issue_commission(user=user_id,

                                                 source=quotas.DEFAULT_SOURCE,

                                                 provisions=commission_info,

                                                 force=False,

                                                 auto_accept=False)

            vm.serial = serial

            # 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

            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_manually

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

           personality=[], network=None, use_backend=None):

    if use_backend is None:

        # Allocate backend to host the server. Commit after allocation to

        # release the locks hold by the backend allocator.

        try:

            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")

        except:

            transaction.rollback()

            raise

        else:

            transaction.commit()

    # 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

    try:

        if network is None:

            # Allocate IP from public network

            (network, address) = util.get_public_ip(use_backend)

            nic = {'ip': address, 'network': network.backend_id}

        else:

            address = util.get_network_free_address(network)

        # 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,

            action="CREATE")

        # 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!

        NetworkInterface.objects.create(machine=vm, network=network, index=0,

                                        ipv4=address, state="BUILDING")

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

        # dispatch server created signal

        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']),

        })

        # Also we must create the VM metadata in the same transaction.

        for key, val in metadata.items():

            VirtualMachineMetadata.objects.create(

                meta_key=key,

                meta_value=val,

                vm=vm)

        # Issue commission to Quotaholder and accept it since at the end of

        # this transaction the VirtualMachine object will be created in the DB.

        # Note: the following call does a commit!

        quotas.issue_and_accept_commission(vm)

    except:

        transaction.rollback()

        raise

    else:

        transaction.commit()

    try:

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

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

        vm.backendjobid = jobID

        vm.task = "BUILD"

        vm.task_job_id = jobID

        vm.save()

        transaction.commit()

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

                 userid, vm, nic, backend, str(jobID))

    except GanetiApiError as e:

        log.exception("Can not communicate to backend %s: %s.",

                      backend, e)

        # Failed while enqueuing OP_INSTANCE_CREATE to backend. Restore

        # already reserved quotas by issuing a negative commission

        vm.operstate = "ERROR"

        vm.backendlogmsg = "Can not communicate to backend."

        vm.deleted = True

        vm.save()

        quotas.issue_and_accept_commission(vm, delete=True)

        raise

    except:

        transaction.rollback()

        raise

    return vm

@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": 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)

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

@server_command("SET_FIREWALL_PROFILE")

def set_firewall_profile(vm, profile):

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

    return None

@server_command("CONNECT")

def connect(vm, network):

    if network.state != 'ACTIVE':

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

    address = None

    if 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)

    return backend.connect_to_network(vm, network, address)

@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("CONNECTING")

def add_floating_ip(vm, address):

    user_id = vm.userid

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

    try:

        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)

    floating_ip.machine = vm

    floating_ip.save()

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

    return backend.connect_to_network(vm, floating_ip.network, address)

@server_command("DISCONNECTING")

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)