pvc/client-cli/cli_lib/vm.py

#!/usr/bin/env python3

# vm.py - PVC CLI client function library, VM functions
# Part of the Parallel Virtual Cluster (PVC) system
#
#    Copyright (C) 2018-2021 Joshua M. Boniface <joshua@boniface.me>
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, version 3.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <https://www.gnu.org/licenses/>.
#
###############################################################################

import time
import re

import cli_lib.ansiprint as ansiprint
from cli_lib.common import call_api, format_bytes, format_metric


#
# Primary functions
#
def vm_info(config, vm):
    """
    Get information about (single) VM

    API endpoint: GET /api/v1/vm/{vm}
    API arguments:
    API schema: {json_data_object}
    """
    response = call_api(config, 'get', '/vm/{vm}'.format(vm=vm))

    if response.status_code == 200:
        if isinstance(response.json(), list) and len(response.json()) != 1:
            # No exact match; return not found
            return False, "VM not found."
        else:
            # Return a single instance if the response is a list
            if isinstance(response.json(), list):
                return True, response.json()[0]
            # This shouldn't happen, but is here just in case
            else:
                return True, response.json()
    else:
        return False, response.json().get('message', '')


def vm_list(config, limit, target_node, target_state):
    """
    Get list information about VMs (limited by {limit}, {target_node}, or {target_state})

    API endpoint: GET /api/v1/vm
    API arguments: limit={limit}, node={target_node}, state={target_state}
    API schema: [{json_data_object},{json_data_object},etc.]
    """
    params = dict()
    if limit:
        params['limit'] = limit
    if target_node:
        params['node'] = target_node
    if target_state:
        params['state'] = target_state

    response = call_api(config, 'get', '/vm', params=params)

    if response.status_code == 200:
        return True, response.json()
    else:
        return False, response.json().get('message', '')


def vm_define(config, xml, node, node_limit, node_selector, node_autostart, migration_method):
    """
    Define a new VM on the cluster

    API endpoint: POST /vm
    API arguments: xml={xml}, node={node}, limit={node_limit}, selector={node_selector}, autostart={node_autostart}, migration_method={migration_method}
    API schema: {"message":"{data}"}
    """
    params = {
        'node': node,
        'limit': node_limit,
        'selector': node_selector,
        'autostart': node_autostart,
        'migration_method': migration_method
    }
    data = {
        'xml': xml
    }
    response = call_api(config, 'post', '/vm', params=params, data=data)

    if response.status_code == 200:
        retstatus = True
    else:
        retstatus = False

    return retstatus, response.json().get('message', '')


def vm_modify(config, vm, xml, restart):
    """
    Modify the configuration of VM

    API endpoint: PUT /vm/{vm}
    API arguments: xml={xml}, restart={restart}
    API schema: {"message":"{data}"}
    """
    params = {
        'restart': restart
    }
    data = {
        'xml': xml
    }
    response = call_api(config, 'put', '/vm/{vm}'.format(vm=vm), params=params, data=data)

    if response.status_code == 200:
        retstatus = True
    else:
        retstatus = False

    return retstatus, response.json().get('message', '')


def vm_rename(config, vm, new_name):
    """
    Rename VM to new name

    API endpoint: POST /vm/{vm}/rename
    API arguments: new_name={new_name}
    API schema: {"message":"{data}"}
    """
    params = {
        'new_name': new_name
    }
    response = call_api(config, 'post', '/vm/{vm}/rename'.format(vm=vm), params=params)

    if response.status_code == 200:
        retstatus = True
    else:
        retstatus = False

    return retstatus, response.json().get('message', '')


def vm_metadata(config, vm, node_limit, node_selector, node_autostart, migration_method, provisioner_profile):
    """
    Modify PVC metadata of a VM

    API endpoint: GET /vm/{vm}/meta,  POST /vm/{vm}/meta
    API arguments: limit={node_limit}, selector={node_selector}, autostart={node_autostart}, migration_method={migration_method} profile={provisioner_profile}
    API schema: {"message":"{data}"}
    """
    params = dict()

    # Update any params that we've sent
    if node_limit is not None:
        params['limit'] = node_limit

    if node_selector is not None:
        params['selector'] = node_selector

    if node_autostart is not None:
        params['autostart'] = node_autostart

    if migration_method is not None:
        params['migration_method'] = migration_method

    if provisioner_profile is not None:
        params['profile'] = provisioner_profile

    # Write the new metadata
    response = call_api(config, 'post', '/vm/{vm}/meta'.format(vm=vm), params=params)

    if response.status_code == 200:
        retstatus = True
    else:
        retstatus = False

    return retstatus, response.json().get('message', '')


def vm_remove(config, vm, delete_disks=False):
    """
    Remove a VM

    API endpoint: DELETE /vm/{vm}
    API arguments: delete_disks={delete_disks}
    API schema: {"message":"{data}"}
    """
    params = {
        'delete_disks': delete_disks
    }
    response = call_api(config, 'delete', '/vm/{vm}'.format(vm=vm), params=params)

    if response.status_code == 200:
        retstatus = True
    else:
        retstatus = False

    return retstatus, response.json().get('message', '')


def vm_state(config, vm, target_state, wait=False):
    """
    Modify the current state of VM

    API endpoint: POST /vm/{vm}/state
    API arguments: state={state}, wait={wait}
    API schema: {"message":"{data}"}
    """
    params = {
        'state': target_state,
        'wait': str(wait).lower()
    }
    response = call_api(config, 'post', '/vm/{vm}/state'.format(vm=vm), params=params)

    if response.status_code == 200:
        retstatus = True
    else:
        retstatus = False

    return retstatus, response.json().get('message', '')


def vm_node(config, vm, target_node, action, force=False, wait=False, force_live=False):
    """
    Modify the current node of VM via {action}

    API endpoint: POST /vm/{vm}/node
    API arguments: node={target_node}, action={action}, force={force}, wait={wait}, force_live={force_live}
    API schema: {"message":"{data}"}
    """
    params = {
        'node': target_node,
        'action': action,
        'force': str(force).lower(),
        'wait': str(wait).lower(),
        'force_live': str(force_live).lower()
    }
    response = call_api(config, 'post', '/vm/{vm}/node'.format(vm=vm), params=params)

    if response.status_code == 200:
        retstatus = True
    else:
        retstatus = False

    return retstatus, response.json().get('message', '')


def vm_locks(config, vm):
    """
    Flush RBD locks of (stopped) VM

    API endpoint: POST /vm/{vm}/locks
    API arguments:
    API schema: {"message":"{data}"}
    """
    response = call_api(config, 'post', '/vm/{vm}/locks'.format(vm=vm))

    if response.status_code == 200:
        retstatus = True
    else:
        retstatus = False

    return retstatus, response.json().get('message', '')


def vm_vcpus_set(config, vm, vcpus, topology, restart):
    """
    Set the vCPU count of the VM with topology

    Calls vm_info to get the VM XML.

    Calls vm_modify to set the VM XML.
    """
    from lxml.objectify import fromstring
    from lxml.etree import tostring

    status, domain_information = vm_info(config, vm)
    if not status:
        return status, domain_information

    xml = domain_information.get('xml', None)
    if xml is None:
        return False, "VM does not have a valid XML doccument."

    try:
        parsed_xml = fromstring(xml)
    except Exception:
        return False, 'ERROR: Failed to parse XML data.'

    parsed_xml.vcpu._setText(str(vcpus))
    parsed_xml.cpu.topology.set('sockets', str(topology[0]))
    parsed_xml.cpu.topology.set('cores', str(topology[1]))
    parsed_xml.cpu.topology.set('threads', str(topology[2]))

    try:
        new_xml = tostring(parsed_xml, pretty_print=True)
    except Exception:
        return False, 'ERROR: Failed to dump XML data.'

    return vm_modify(config, vm, new_xml, restart)


def vm_vcpus_get(config, vm):
    """
    Get the vCPU count of the VM

    Calls vm_info to get VM XML.

    Returns a tuple of (vcpus, (sockets, cores, threads))
    """
    from lxml.objectify import fromstring

    status, domain_information = vm_info(config, vm)
    if not status:
        return status, domain_information

    xml = domain_information.get('xml', None)
    if xml is None:
        return False, "VM does not have a valid XML doccument."

    try:
        parsed_xml = fromstring(xml)
    except Exception:
        return False, 'ERROR: Failed to parse XML data.'

    vm_vcpus = int(parsed_xml.vcpu.text)
    vm_sockets = parsed_xml.cpu.topology.attrib.get('sockets')
    vm_cores = parsed_xml.cpu.topology.attrib.get('cores')
    vm_threads = parsed_xml.cpu.topology.attrib.get('threads')

    return True, (vm_vcpus, (vm_sockets, vm_cores, vm_threads))


def format_vm_vcpus(config, name, vcpus):
    """
    Format the output of a vCPU value in a nice table
    """
    output_list = []

    name_length = 5
    _name_length = len(name) + 1
    if _name_length > name_length:
        name_length = _name_length

    vcpus_length = 6
    sockets_length = 8
    cores_length = 6
    threads_length = 8

    output_list.append(
        '{bold}{name: <{name_length}}  \
{vcpus: <{vcpus_length}}   \
{sockets: <{sockets_length}} \
{cores: <{cores_length}} \
{threads: <{threads_length}}{end_bold}'.format(
            name_length=name_length,
            vcpus_length=vcpus_length,
            sockets_length=sockets_length,
            cores_length=cores_length,
            threads_length=threads_length,
            bold=ansiprint.bold(),
            end_bold=ansiprint.end(),
            name='Name',
            vcpus='vCPUs',
            sockets='Sockets',
            cores='Cores',
            threads='Threads'
        )
    )
    output_list.append(
        '{bold}{name: <{name_length}}  \
{vcpus: <{vcpus_length}}   \
{sockets: <{sockets_length}} \
{cores: <{cores_length}} \
{threads: <{threads_length}}{end_bold}'.format(
            name_length=name_length,
            vcpus_length=vcpus_length,
            sockets_length=sockets_length,
            cores_length=cores_length,
            threads_length=threads_length,
            bold='',
            end_bold='',
            name=name,
            vcpus=vcpus[0],
            sockets=vcpus[1][0],
            cores=vcpus[1][1],
            threads=vcpus[1][2]
        )
    )
    return '\n'.join(output_list)


def vm_memory_set(config, vm, memory, restart):
    """
    Set the provisioned memory of the VM with topology

    Calls vm_info to get the VM XML.

    Calls vm_modify to set the VM XML.
    """
    from lxml.objectify import fromstring
    from lxml.etree import tostring

    status, domain_information = vm_info(config, vm)
    if not status:
        return status, domain_information

    xml = domain_information.get('xml', None)
    if xml is None:
        return False, "VM does not have a valid XML doccument."

    try:
        parsed_xml = fromstring(xml)
    except Exception:
        return False, 'ERROR: Failed to parse XML data.'

    parsed_xml.memory._setText(str(memory))

    try:
        new_xml = tostring(parsed_xml, pretty_print=True)
    except Exception:
        return False, 'ERROR: Failed to dump XML data.'

    return vm_modify(config, vm, new_xml, restart)


def vm_memory_get(config, vm):
    """
    Get the provisioned memory of the VM

    Calls vm_info to get VM XML.

    Returns an integer memory value.
    """
    from lxml.objectify import fromstring

    status, domain_information = vm_info(config, vm)
    if not status:
        return status, domain_information

    xml = domain_information.get('xml', None)
    if xml is None:
        return False, "VM does not have a valid XML doccument."

    try:
        parsed_xml = fromstring(xml)
    except Exception:
        return False, 'ERROR: Failed to parse XML data.'

    vm_memory = int(parsed_xml.memory.text)

    return True, vm_memory


def format_vm_memory(config, name, memory):
    """
    Format the output of a memory value in a nice table
    """
    output_list = []

    name_length = 5
    _name_length = len(name) + 1
    if _name_length > name_length:
        name_length = _name_length

    memory_length = 6

    output_list.append(
        '{bold}{name: <{name_length}}  \
{memory: <{memory_length}}{end_bold}'.format(
            name_length=name_length,
            memory_length=memory_length,
            bold=ansiprint.bold(),
            end_bold=ansiprint.end(),
            name='Name',
            memory='RAM (M)'
        )
    )
    output_list.append(
        '{bold}{name: <{name_length}}  \
{memory: <{memory_length}}{end_bold}'.format(
            name_length=name_length,
            memory_length=memory_length,
            bold='',
            end_bold='',
            name=name,
            memory=memory
        )
    )
    return '\n'.join(output_list)


def vm_networks_add(config, vm, network, macaddr, model, sriov, sriov_mode, restart):
    """
    Add a new network to the VM

    Calls vm_info to get the VM XML.

    Calls vm_modify to set the VM XML.
    """
    from lxml.objectify import fromstring
    from lxml.etree import tostring
    from random import randint
    import cli_lib.network as pvc_network

    # Verify that the provided network is valid (not in SR-IOV mode)
    if not sriov:
        retcode, retdata = pvc_network.net_info(config, network)
        if not retcode:
            # Ignore the three special networks
            if network not in ['upstream', 'cluster', 'storage']:
                return False, "Network {} is not present in the cluster.".format(network)

        # Set the bridge prefix
        if network in ['upstream', 'cluster', 'storage']:
            br_prefix = 'br'
        else:
            br_prefix = 'vmbr'

    status, domain_information = vm_info(config, vm)
    if not status:
        return status, domain_information

    xml = domain_information.get('xml', None)
    if xml is None:
        return False, "VM does not have a valid XML doccument."

    try:
        parsed_xml = fromstring(xml)
    except Exception:
        return False, 'ERROR: Failed to parse XML data.'

    if macaddr is None:
        mac_prefix = '52:54:00'
        random_octet_A = '{:x}'.format(randint(16, 238))
        random_octet_B = '{:x}'.format(randint(16, 238))
        random_octet_C = '{:x}'.format(randint(16, 238))
        macaddr = '{prefix}:{octetA}:{octetB}:{octetC}'.format(
            prefix=mac_prefix,
            octetA=random_octet_A,
            octetB=random_octet_B,
            octetC=random_octet_C
        )

    # Add an SR-IOV network
    if sriov:
        valid, sriov_vf_information = pvc_network.net_sriov_vf_info(config, domain_information['node'], network)
        if not valid:
            return False, 'Specified SR-IOV VF "{}" does not exist on VM node "{}".'.format(network, domain_information['node'])

        # Add a hostdev (direct PCIe) SR-IOV network
        if sriov_mode == 'hostdev':
            bus_address = 'domain="0x{pci_domain}" bus="0x{pci_bus}" slot="0x{pci_slot}" function="0x{pci_function}"'.format(
                pci_domain=sriov_vf_information['pci']['domain'],
                pci_bus=sriov_vf_information['pci']['bus'],
                pci_slot=sriov_vf_information['pci']['slot'],
                pci_function=sriov_vf_information['pci']['function'],
            )
            device_string = '<interface type="hostdev" managed="yes"><mac address="{macaddr}"/><source><address type="pci" {bus_address}/></source><sriov_device>{network}</sriov_device></interface>'.format(
                macaddr=macaddr,
                bus_address=bus_address,
                network=network
            )
        # Add a macvtap SR-IOV network
        elif sriov_mode == 'macvtap':
            device_string = '<interface type="direct"><mac address="{macaddr}"/><source dev="{network}" mode="passthrough"/><model type="{model}"/></interface>'.format(
                macaddr=macaddr,
                network=network,
                model=model
            )
        else:
            return False, "ERROR: Invalid SR-IOV mode specified."
    # Add a normal bridged PVC network
    else:
        device_string = '<interface type="bridge"><mac address="{macaddr}"/><source bridge="{bridge}"/><model type="{model}"/></interface>'.format(
            macaddr=macaddr,
            bridge="{}{}".format(br_prefix, network),
            model=model
        )

    device_xml = fromstring(device_string)

    all_interfaces = parsed_xml.devices.find('interface')
    if all_interfaces is None:
        all_interfaces = []
    for interface in all_interfaces:
        if sriov:
            if sriov_mode == 'hostdev':
                if interface.attrib.get('type') == 'hostdev':
                    interface_address = 'domain="{pci_domain}" bus="{pci_bus}" slot="{pci_slot}" function="{pci_function}"'.format(
                        pci_domain=interface.source.address.attrib.get('domain'),
                        pci_bus=interface.source.address.attrib.get('bus'),
                        pci_slot=interface.source.address.attrib.get('slot'),
                        pci_function=interface.source.address.attrib.get('function')
                    )
                    if interface_address == bus_address:
                        return False, 'Network "{}" is already configured for VM "{}".'.format(network, vm)
            elif sriov_mode == 'macvtap':
                if interface.attrib.get('type') == 'direct':
                    interface_dev = interface.source.attrib.get('dev')
                    if interface_dev == network:
                        return False, 'Network "{}" is already configured for VM "{}".'.format(network, vm)
        else:
            if interface.attrib.get('type') == 'bridge':
                interface_vni = re.match(r'[vm]*br([0-9a-z]+)', interface.source.attrib.get('bridge')).group(1)
                if interface_vni == network:
                    return False, 'Network "{}" is already configured for VM "{}".'.format(network, vm)

    # Add the interface at the end of the list (or, right above emulator)
    if len(all_interfaces) > 0:
        for idx, interface in enumerate(parsed_xml.devices.find('interface')):
            if idx == len(all_interfaces) - 1:
                interface.addnext(device_xml)
    else:
        parsed_xml.devices.find('emulator').addprevious(device_xml)

    try:
        new_xml = tostring(parsed_xml, pretty_print=True)
    except Exception:
        return False, 'ERROR: Failed to dump XML data.'

    return vm_modify(config, vm, new_xml, restart)


def vm_networks_remove(config, vm, network, sriov, restart):
    """
    Remove a network to the VM

    Calls vm_info to get the VM XML.

    Calls vm_modify to set the VM XML.
    """
    from lxml.objectify import fromstring
    from lxml.etree import tostring

    status, domain_information = vm_info(config, vm)
    if not status:
        return status, domain_information

    xml = domain_information.get('xml', None)
    if xml is None:
        return False, "VM does not have a valid XML doccument."

    try:
        parsed_xml = fromstring(xml)
    except Exception:
        return False, 'ERROR: Failed to parse XML data.'

    changed = False
    for interface in parsed_xml.devices.find('interface'):
        if sriov:
            if interface.attrib.get('type') == 'hostdev':
                if_dev = str(interface.sriov_device)
                if network == if_dev:
                    interface.getparent().remove(interface)
                    changed = True
            elif interface.attrib.get('type') == 'direct':
                if_dev = str(interface.source.attrib.get('dev'))
                if network == if_dev:
                    interface.getparent().remove(interface)
                    changed = True
        else:
            if_vni = re.match(r'[vm]*br([0-9a-z]+)', interface.source.attrib.get('bridge')).group(1)
            if network == if_vni:
                interface.getparent().remove(interface)
                changed = True
    if changed:
        try:
            new_xml = tostring(parsed_xml, pretty_print=True)
        except Exception:
            return False, 'ERROR: Failed to dump XML data.'

        return vm_modify(config, vm, new_xml, restart)
    else:
        return False, 'ERROR: Network "{}" does not exist on VM.'.format(network)


def vm_networks_get(config, vm):
    """
    Get the networks of the VM

    Calls vm_info to get VM XML.

    Returns a list of tuples of (network_vni, mac_address, model)
    """
    from lxml.objectify import fromstring

    status, domain_information = vm_info(config, vm)
    if not status:
        return status, domain_information

    xml = domain_information.get('xml', None)
    if xml is None:
        return False, "VM does not have a valid XML doccument."

    try:
        parsed_xml = fromstring(xml)
    except Exception:
        return False, 'ERROR: Failed to parse XML data.'

    network_data = list()
    for interface in parsed_xml.devices.find('interface'):
        mac_address = interface.mac.attrib.get('address')
        model = interface.model.attrib.get('type')
        network = re.match(r'[vm]*br([0-9a-z]+)', interface.source.attrib.get('bridge')).group(1)
        network_data.append((network, mac_address, model))

    return True, network_data


def format_vm_networks(config, name, networks):
    """
    Format the output of a network list in a nice table
    """
    output_list = []

    name_length = 5
    vni_length = 8
    macaddr_length = 12
    model_length = 6

    _name_length = len(name) + 1
    if _name_length > name_length:
        name_length = _name_length

    for network in networks:
        _vni_length = len(network[0]) + 1
        if _vni_length > vni_length:
            vni_length = _vni_length

        _macaddr_length = len(network[1]) + 1
        if _macaddr_length > macaddr_length:
            macaddr_length = _macaddr_length

        _model_length = len(network[2]) + 1
        if _model_length > model_length:
            model_length = _model_length

    output_list.append(
        '{bold}{name: <{name_length}}  \
{vni: <{vni_length}} \
{macaddr: <{macaddr_length}} \
{model: <{model_length}}{end_bold}'.format(
            name_length=name_length,
            vni_length=vni_length,
            macaddr_length=macaddr_length,
            model_length=model_length,
            bold=ansiprint.bold(),
            end_bold=ansiprint.end(),
            name='Name',
            vni='Network',
            macaddr='MAC Address',
            model='Model'
        )
    )
    count = 0
    for network in networks:
        if count > 0:
            name = ''
        count += 1
        output_list.append(
            '{bold}{name: <{name_length}}  \
{vni: <{vni_length}} \
{macaddr: <{macaddr_length}} \
{model: <{model_length}}{end_bold}'.format(
                name_length=name_length,
                vni_length=vni_length,
                macaddr_length=macaddr_length,
                model_length=model_length,
                bold='',
                end_bold='',
                name=name,
                vni=network[0],
                macaddr=network[1],
                model=network[2]
            )
        )
    return '\n'.join(output_list)


def vm_volumes_add(config, vm, volume, disk_id, bus, disk_type, restart):
    """
    Add a new volume to the VM

    Calls vm_info to get the VM XML.

    Calls vm_modify to set the VM XML.
    """
    from lxml.objectify import fromstring
    from lxml.etree import tostring
    from copy import deepcopy
    import cli_lib.ceph as pvc_ceph

    if disk_type == 'rbd':
        # Verify that the provided volume is valid
        vpool = volume.split('/')[0]
        vname = volume.split('/')[1]
        retcode, retdata = pvc_ceph.ceph_volume_info(config, vpool, vname)
        if not retcode:
            return False, "Volume {} is not present in the cluster.".format(volume)

    status, domain_information = vm_info(config, vm)
    if not status:
        return status, domain_information

    xml = domain_information.get('xml', None)
    if xml is None:
        return False, "VM does not have a valid XML doccument."

    try:
        parsed_xml = fromstring(xml)
    except Exception:
        return False, 'ERROR: Failed to parse XML data.'

    last_disk = None
    id_list = list()
    all_disks = parsed_xml.devices.find('disk')
    if all_disks is None:
        all_disks = []
    for disk in all_disks:
        id_list.append(disk.target.attrib.get('dev'))
        if disk.source.attrib.get('protocol') == disk_type:
            if disk_type == 'rbd':
                last_disk = disk.source.attrib.get('name')
            elif disk_type == 'file':
                last_disk = disk.source.attrib.get('file')
            if last_disk == volume:
                return False, 'Volume {} is already configured for VM {}.'.format(volume, vm)
            last_disk_details = deepcopy(disk)

    if disk_id is not None:
        if disk_id in id_list:
            return False, 'Manually specified disk ID {} is already in use for VM {}.'.format(disk_id, vm)
    else:
        # Find the next free disk ID
        first_dev_prefix = id_list[0][0:-1]

        for char in range(ord('a'), ord('z')):
            char = chr(char)
            next_id = "{}{}".format(first_dev_prefix, char)
            if next_id not in id_list:
                break
            else:
                next_id = None
        if next_id is None:
            return False, 'Failed to find a valid disk_id and none specified; too many disks for VM {}?'.format(vm)
        disk_id = next_id

    if last_disk is None:
        if disk_type == 'rbd':
            # RBD volumes need an example to be based on
            return False, "There are no existing RBD volumes attached to this VM. Autoconfiguration failed; use the 'vm modify' command to manually configure this volume with the required details for authentication, hosts, etc.."
        elif disk_type == 'file':
            # File types can be added ad-hoc
            disk_template = '<disk type="file" device="disk"><driver name="qemu" type="raw"/><source file="{source}"/><target dev="{dev}" bus="{bus}"/></disk>'.format(
                source=volume,
                dev=disk_id,
                bus=bus
            )
            last_disk_details = fromstring(disk_template)

    new_disk_details = last_disk_details
    new_disk_details.target.set('dev', disk_id)
    new_disk_details.target.set('bus', bus)
    if disk_type == 'rbd':
        new_disk_details.source.set('name', volume)
    elif disk_type == 'file':
        new_disk_details.source.set('file', volume)

    all_disks = parsed_xml.devices.find('disk')
    if all_disks is None:
        all_disks = []
    for disk in all_disks:
        last_disk = disk

    if last_disk is None:
        parsed_xml.devices.find('emulator').addprevious(new_disk_details)

    try:
        new_xml = tostring(parsed_xml, pretty_print=True)
    except Exception:
        return False, 'ERROR: Failed to dump XML data.'

    return vm_modify(config, vm, new_xml, restart)


def vm_volumes_remove(config, vm, volume, restart):
    """
    Remove a volume to the VM

    Calls vm_info to get the VM XML.

    Calls vm_modify to set the VM XML.
    """
    from lxml.objectify import fromstring
    from lxml.etree import tostring

    status, domain_information = vm_info(config, vm)
    if not status:
        return status, domain_information

    xml = domain_information.get('xml', None)
    if xml is None:
        return False, "VM does not have a valid XML document."

    try:
        parsed_xml = fromstring(xml)
    except Exception:
        return False, 'ERROR: Failed to parse XML data.'

    for disk in parsed_xml.devices.find('disk'):
        disk_name = disk.source.attrib.get('name')
        if not disk_name:
            disk_name = disk.source.attrib.get('file')
        if volume == disk_name:
            disk.getparent().remove(disk)

    try:
        new_xml = tostring(parsed_xml, pretty_print=True)
    except Exception:
        return False, 'ERROR: Failed to dump XML data.'

    return vm_modify(config, vm, new_xml, restart)


def vm_volumes_get(config, vm):
    """
    Get the volumes of the VM

    Calls vm_info to get VM XML.

    Returns a list of tuples of (volume, disk_id, type, bus)
    """
    from lxml.objectify import fromstring

    status, domain_information = vm_info(config, vm)
    if not status:
        return status, domain_information

    xml = domain_information.get('xml', None)
    if xml is None:
        return False, "VM does not have a valid XML doccument."

    try:
        parsed_xml = fromstring(xml)
    except Exception:
        return False, 'ERROR: Failed to parse XML data.'

    volume_data = list()
    for disk in parsed_xml.devices.find('disk'):
        protocol = disk.attrib.get('type')
        disk_id = disk.target.attrib.get('dev')
        bus = disk.target.attrib.get('bus')
        if protocol == 'network':
            protocol = disk.source.attrib.get('protocol')
            source = disk.source.attrib.get('name')
        elif protocol == 'file':
            protocol = 'file'
            source = disk.source.attrib.get('file')
        else:
            protocol = 'unknown'
            source = 'unknown'

        volume_data.append((source, disk_id, protocol, bus))

    return True, volume_data


def format_vm_volumes(config, name, volumes):
    """
    Format the output of a volume value in a nice table
    """
    output_list = []

    name_length = 5
    volume_length = 7
    disk_id_length = 4
    protocol_length = 5
    bus_length = 4

    _name_length = len(name) + 1
    if _name_length > name_length:
        name_length = _name_length

    for volume in volumes:
        _volume_length = len(volume[0]) + 1
        if _volume_length > volume_length:
            volume_length = _volume_length

        _disk_id_length = len(volume[1]) + 1
        if _disk_id_length > disk_id_length:
            disk_id_length = _disk_id_length

        _protocol_length = len(volume[2]) + 1
        if _protocol_length > protocol_length:
            protocol_length = _protocol_length

        _bus_length = len(volume[3]) + 1
        if _bus_length > bus_length:
            bus_length = _bus_length

    output_list.append(
        '{bold}{name: <{name_length}}  \
{volume: <{volume_length}} \
{disk_id: <{disk_id_length}} \
{protocol: <{protocol_length}} \
{bus: <{bus_length}}{end_bold}'.format(
            name_length=name_length,
            volume_length=volume_length,
            disk_id_length=disk_id_length,
            protocol_length=protocol_length,
            bus_length=bus_length,
            bold=ansiprint.bold(),
            end_bold=ansiprint.end(),
            name='Name',
            volume='Volume',
            disk_id='Dev',
            protocol='Type',
            bus='Bus'
        )
    )
    count = 0
    for volume in volumes:
        if count > 0:
            name = ''
        count += 1
        output_list.append(
            '{bold}{name: <{name_length}}  \
{volume: <{volume_length}} \
{disk_id: <{disk_id_length}} \
{protocol: <{protocol_length}} \
{bus: <{bus_length}}{end_bold}'.format(
                name_length=name_length,
                volume_length=volume_length,
                disk_id_length=disk_id_length,
                protocol_length=protocol_length,
                bus_length=bus_length,
                bold='',
                end_bold='',
                name=name,
                volume=volume[0],
                disk_id=volume[1],
                protocol=volume[2],
                bus=volume[3]
            )
        )
    return '\n'.join(output_list)


def view_console_log(config, vm, lines=100):
    """
    Return console log lines from the API (and display them in a pager in the main CLI)

    API endpoint: GET /vm/{vm}/console
    API arguments: lines={lines}
    API schema: {"name":"{vmname}","data":"{console_log}"}
    """
    params = {
        'lines': lines
    }
    response = call_api(config, 'get', '/vm/{vm}/console'.format(vm=vm), params=params)

    if response.status_code != 200:
        return False, response.json().get('message', '')

    console_log = response.json()['data']

    # Shrink the log buffer to length lines
    shrunk_log = console_log.split('\n')[-lines:]
    loglines = '\n'.join(shrunk_log)

    return True, loglines


def follow_console_log(config, vm, lines=10):
    """
    Return and follow console log lines from the API

    API endpoint: GET /vm/{vm}/console
    API arguments: lines={lines}
    API schema: {"name":"{vmname}","data":"{console_log}"}
    """
    # We always grab 500 to match the follow call, but only _show_ `lines` number
    params = {
        'lines': 500
    }
    response = call_api(config, 'get', '/vm/{vm}/console'.format(vm=vm), params=params)

    if response.status_code != 200:
        return False, response.json().get('message', '')

    # Shrink the log buffer to length lines
    console_log = response.json()['data']
    shrunk_log = console_log.split('\n')[-int(lines):]
    loglines = '\n'.join(shrunk_log)

    # Print the initial data and begin following
    print(loglines, end='')

    while True:
        # Grab the next line set (500 is a reasonable number of lines per second; any more are skipped)
        try:
            params = {
                'lines': 500
            }
            response = call_api(config, 'get', '/vm/{vm}/console'.format(vm=vm), params=params)
            new_console_log = response.json()['data']
        except Exception:
            break
        # Split the new and old log strings into constitutent lines
        old_console_loglines = console_log.split('\n')
        new_console_loglines = new_console_log.split('\n')
        # Set the console log to the new log value for the next iteration
        console_log = new_console_log
        # Remove the lines from the old log until we hit the first line of the new log; this
        # ensures that the old log is a string that we can remove from the new log entirely
        for index, line in enumerate(old_console_loglines, start=0):
            if line == new_console_loglines[0]:
                del old_console_loglines[0:index]
                break
        # Rejoin the log lines into strings
        old_console_log = '\n'.join(old_console_loglines)
        new_console_log = '\n'.join(new_console_loglines)
        # Remove the old lines from the new log
        diff_console_log = new_console_log.replace(old_console_log, "")
        # If there's a difference, print it out
        if diff_console_log:
            print(diff_console_log, end='')
        # Wait a second
        time.sleep(1)

    return True, ''


#
# Output display functions
#
def format_info(config, domain_information, long_output):
    # Format a nice output; do this line-by-line then concat the elements at the end
    ainformation = []
    ainformation.append('{}Virtual machine information:{}'.format(ansiprint.bold(), ansiprint.end()))
    ainformation.append('')
    # Basic information
    ainformation.append('{}UUID:{}               {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['uuid']))
    ainformation.append('{}Name:{}               {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['name']))
    ainformation.append('{}Description:{}        {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['description']))
    ainformation.append('{}Profile:{}            {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['profile']))
    ainformation.append('{}Memory (M):{}         {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['memory']))
    ainformation.append('{}vCPUs:{}              {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['vcpu']))
    ainformation.append('{}Topology (S/C/T):{}   {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['vcpu_topology']))

    if domain_information['vnc'].get('listen', 'None') != 'None' and domain_information['vnc'].get('port', 'None') != 'None':
        ainformation.append('')
        ainformation.append('{}VNC listen:{}         {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['vnc']['listen']))
        ainformation.append('{}VNC port:{}           {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['vnc']['port']))

    if long_output is True:
        # Virtualization information
        ainformation.append('')
        ainformation.append('{}Emulator:{}           {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['emulator']))
        ainformation.append('{}Type:{}               {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['type']))
        ainformation.append('{}Arch:{}               {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['arch']))
        ainformation.append('{}Machine:{}            {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['machine']))
        ainformation.append('{}Features:{}           {}'.format(ansiprint.purple(), ansiprint.end(), ' '.join(domain_information['features'])))
        ainformation.append('')
        ainformation.append('{0}Memory stats:{1}       {2}Swap In  Swap Out  Faults (maj/min)  Available  Usable  Unused  RSS{3}'.format(ansiprint.purple(), ansiprint.end(), ansiprint.bold(), ansiprint.end()))
        ainformation.append('                    {0: <7}  {1: <8}  {2: <16}  {3: <10} {4: <7} {5: <7} {6: <10}'.format(
            format_metric(domain_information['memory_stats'].get('swap_in', 0)),
            format_metric(domain_information['memory_stats'].get('swap_out', 0)),
            '/'.join([format_metric(domain_information['memory_stats'].get('major_fault', 0)), format_metric(domain_information['memory_stats'].get('minor_fault', 0))]),
            format_bytes(domain_information['memory_stats'].get('available', 0) * 1024),
            format_bytes(domain_information['memory_stats'].get('usable', 0) * 1024),
            format_bytes(domain_information['memory_stats'].get('unused', 0) * 1024),
            format_bytes(domain_information['memory_stats'].get('rss', 0) * 1024)
        ))
        ainformation.append('')
        ainformation.append('{0}vCPU stats:{1}         {2}CPU time (ns)     User time (ns)    System time (ns){3}'.format(ansiprint.purple(), ansiprint.end(), ansiprint.bold(), ansiprint.end()))
        ainformation.append('                    {0: <16}  {1: <16}  {2: <15}'.format(
            str(domain_information['vcpu_stats'].get('cpu_time', 0)),
            str(domain_information['vcpu_stats'].get('user_time', 0)),
            str(domain_information['vcpu_stats'].get('system_time', 0))
        ))

    # PVC cluster information
    ainformation.append('')
    dstate_colour = {
        'start': ansiprint.green(),
        'restart': ansiprint.yellow(),
        'shutdown': ansiprint.yellow(),
        'stop': ansiprint.red(),
        'disable': ansiprint.blue(),
        'fail': ansiprint.red(),
        'migrate': ansiprint.blue(),
        'unmigrate': ansiprint.blue(),
        'provision': ansiprint.blue()
    }
    ainformation.append('{}State:{}              {}{}{}'.format(ansiprint.purple(), ansiprint.end(), dstate_colour[domain_information['state']], domain_information['state'], ansiprint.end()))
    ainformation.append('{}Current Node:{}       {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['node']))
    if not domain_information['last_node']:
        domain_information['last_node'] = "N/A"
    ainformation.append('{}Previous Node:{}      {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['last_node']))

    # Get a failure reason if applicable
    if domain_information['failed_reason']:
        ainformation.append('')
        ainformation.append('{}Failure reason:{}     {}'.format(ansiprint.purple(), ansiprint.end(), domain_information['failed_reason']))

    if not domain_information.get('node_selector'):
        formatted_node_selector = "False"
    else:
        formatted_node_selector = domain_information['node_selector']

    if not domain_information.get('node_limit'):
        formatted_node_limit = "False"
    else:
        formatted_node_limit = ', '.join(domain_information['node_limit'])

    if not domain_information.get('node_autostart'):
        formatted_node_autostart = "False"
    else:
        formatted_node_autostart = domain_information['node_autostart']

    if not domain_information.get('migration_method'):
        formatted_migration_method = "any"
    else:
        formatted_migration_method = domain_information['migration_method']

    ainformation.append('{}Migration selector:{} {}'.format(ansiprint.purple(), ansiprint.end(), formatted_node_selector))
    ainformation.append('{}Node limit:{}         {}'.format(ansiprint.purple(), ansiprint.end(), formatted_node_limit))
    ainformation.append('{}Autostart:{}          {}'.format(ansiprint.purple(), ansiprint.end(), formatted_node_autostart))
    ainformation.append('{}Migration Method:{}   {}'.format(ansiprint.purple(), ansiprint.end(), formatted_migration_method))

    # Network list
    net_list = []
    cluster_net_list = call_api(config, 'get', '/network').json()
    for net in domain_information['networks']:
        net_vni = net['vni']
        if net_vni not in ['cluster', 'storage', 'upstream'] and not re.match(r'^macvtap:.*', net_vni) and not re.match(r'^hostdev:.*', net_vni):
            if int(net_vni) not in [net['vni'] for net in cluster_net_list]:
                net_list.append(ansiprint.red() + net_vni + ansiprint.end() + ' [invalid]')
            else:
                net_list.append(net_vni)
        else:
            net_list.append(net_vni)

    ainformation.append('')
    ainformation.append('{}Networks:{}           {}'.format(ansiprint.purple(), ansiprint.end(), ', '.join(net_list)))

    if long_output is True:
        # Disk list
        ainformation.append('')
        name_length = 0
        for disk in domain_information['disks']:
            _name_length = len(disk['name']) + 1
            if _name_length > name_length:
                name_length = _name_length
        ainformation.append('{0}Disks:{1}        {2}ID  Type  {3: <{width}} Dev  Bus    Requests (r/w)   Data (r/w){4}'.format(ansiprint.purple(), ansiprint.end(), ansiprint.bold(), 'Name', ansiprint.end(), width=name_length))
        for disk in domain_information['disks']:
            ainformation.append('              {0: <3} {1: <5} {2: <{width}} {3: <4} {4: <5}  {5: <15}  {6}'.format(
                domain_information['disks'].index(disk),
                disk['type'],
                disk['name'],
                disk['dev'],
                disk['bus'],
                '/'.join([str(format_metric(disk.get('rd_req', 0))), str(format_metric(disk.get('wr_req', 0)))]),
                '/'.join([str(format_bytes(disk.get('rd_bytes', 0))), str(format_bytes(disk.get('wr_bytes', 0)))]),
                width=name_length
            ))
        ainformation.append('')
        ainformation.append('{}Interfaces:{}   {}ID  Type     Source       Model    MAC                 Data (r/w)   Packets (r/w)   Errors (r/w){}'.format(ansiprint.purple(), ansiprint.end(), ansiprint.bold(), ansiprint.end()))
        for net in domain_information['networks']:
            net_type = net['type']
            net_source = net['source']
            net_mac = net['mac']
            if net_type in ['direct', 'hostdev']:
                net_model = 'N/A'
                net_bytes = 'N/A'
                net_packets = 'N/A'
                net_errors = 'N/A'
            elif net_type in ['bridge']:
                net_model = net['model']
                net_bytes = '/'.join([str(format_bytes(net.get('rd_bytes', 0))), str(format_bytes(net.get('wr_bytes', 0)))])
                net_packets = '/'.join([str(format_metric(net.get('rd_packets', 0))), str(format_metric(net.get('wr_packets', 0)))])
                net_errors = '/'.join([str(format_metric(net.get('rd_errors', 0))), str(format_metric(net.get('wr_errors', 0)))])

            ainformation.append('              {0: <3} {1: <8} {2: <12} {3: <8} {4: <18}  {5: <12} {6: <15} {7: <12}'.format(
                domain_information['networks'].index(net),
                net_type,
                net_source,
                net_model,
                net_mac,
                net_bytes,
                net_packets,
                net_errors
            ))
        # Controller list
        ainformation.append('')
        ainformation.append('{}Controllers:{}  {}ID  Type           Model{}'.format(ansiprint.purple(), ansiprint.end(), ansiprint.bold(), ansiprint.end()))
        for controller in domain_information['controllers']:
            ainformation.append('              {0: <3} {1: <14} {2: <8}'.format(domain_information['controllers'].index(controller), controller['type'], str(controller['model'])))

    # Join it all together
    ainformation.append('')
    return '\n'.join(ainformation)


def format_list(config, vm_list, raw):
    # Function to strip the "br" off of nets and return a nicer list
    def getNiceNetID(domain_information):
        # Network list
        net_list = []
        for net in domain_information['networks']:
            net_list.append(net['vni'])
        return net_list

    # Handle raw mode since it just lists the names
    if raw:
        ainformation = list()
        for vm in sorted(item['name'] for item in vm_list):
            ainformation.append(vm)
        return '\n'.join(ainformation)

    vm_list_output = []

    # Determine optimal column widths
    # Dynamic columns: node_name, node, migrated
    vm_name_length = 5
    vm_uuid_length = 37
    vm_state_length = 6
    vm_nets_length = 9
    vm_ram_length = 8
    vm_vcpu_length = 6
    vm_node_length = 5
    vm_migrated_length = 10
    for domain_information in vm_list:
        net_list = getNiceNetID(domain_information)
        # vm_name column
        _vm_name_length = len(domain_information['name']) + 1
        if _vm_name_length > vm_name_length:
            vm_name_length = _vm_name_length
        # vm_state column
        _vm_state_length = len(domain_information['state']) + 1
        if _vm_state_length > vm_state_length:
            vm_state_length = _vm_state_length
        # vm_nets column
        _vm_nets_length = len(','.join(net_list)) + 1
        if _vm_nets_length > vm_nets_length:
            vm_nets_length = _vm_nets_length
        # vm_node column
        _vm_node_length = len(domain_information['node']) + 1
        if _vm_node_length > vm_node_length:
            vm_node_length = _vm_node_length
        # vm_migrated column
        _vm_migrated_length = len(domain_information['migrated']) + 1
        if _vm_migrated_length > vm_migrated_length:
            vm_migrated_length = _vm_migrated_length

    # Format the string (header)
    vm_list_output.append(
        '{bold}{vm_name: <{vm_name_length}} {vm_uuid: <{vm_uuid_length}} \
{vm_state_colour}{vm_state: <{vm_state_length}}{end_colour} \
{vm_networks: <{vm_nets_length}} \
{vm_memory: <{vm_ram_length}} {vm_vcpu: <{vm_vcpu_length}} \
{vm_node: <{vm_node_length}} \
{vm_migrated: <{vm_migrated_length}}{end_bold}'.format(
            vm_name_length=vm_name_length,
            vm_uuid_length=vm_uuid_length,
            vm_state_length=vm_state_length,
            vm_nets_length=vm_nets_length,
            vm_ram_length=vm_ram_length,
            vm_vcpu_length=vm_vcpu_length,
            vm_node_length=vm_node_length,
            vm_migrated_length=vm_migrated_length,
            bold=ansiprint.bold(),
            end_bold=ansiprint.end(),
            vm_state_colour='',
            end_colour='',
            vm_name='Name',
            vm_uuid='UUID',
            vm_state='State',
            vm_networks='Networks',
            vm_memory='RAM (M)',
            vm_vcpu='vCPUs',
            vm_node='Node',
            vm_migrated='Migrated'
        )
    )

    # Format the string (elements)
    for domain_information in vm_list:
        if domain_information['state'] == 'start':
            vm_state_colour = ansiprint.green()
        elif domain_information['state'] == 'restart':
            vm_state_colour = ansiprint.yellow()
        elif domain_information['state'] == 'shutdown':
            vm_state_colour = ansiprint.yellow()
        elif domain_information['state'] == 'stop':
            vm_state_colour = ansiprint.red()
        elif domain_information['state'] == 'fail':
            vm_state_colour = ansiprint.red()
        else:
            vm_state_colour = ansiprint.blue()

        # Handle colouring for an invalid network config
        net_list = getNiceNetID(domain_information)
        cluster_net_list = call_api(config, 'get', '/network').json()
        vm_net_colour = ''
        for net_vni in net_list:
            if net_vni not in ['cluster', 'storage', 'upstream'] and not re.match(r'^macvtap:.*', net_vni) and not re.match(r'^hostdev:.*', net_vni):
                if int(net_vni) not in [net['vni'] for net in cluster_net_list]:
                    vm_net_colour = ansiprint.red()

        vm_list_output.append(
            '{bold}{vm_name: <{vm_name_length}} {vm_uuid: <{vm_uuid_length}} \
{vm_state_colour}{vm_state: <{vm_state_length}}{end_colour} \
{vm_net_colour}{vm_networks: <{vm_nets_length}}{end_colour} \
{vm_memory: <{vm_ram_length}} {vm_vcpu: <{vm_vcpu_length}} \
{vm_node: <{vm_node_length}} \
{vm_migrated: <{vm_migrated_length}}{end_bold}'.format(
                vm_name_length=vm_name_length,
                vm_uuid_length=vm_uuid_length,
                vm_state_length=vm_state_length,
                vm_nets_length=vm_nets_length,
                vm_ram_length=vm_ram_length,
                vm_vcpu_length=vm_vcpu_length,
                vm_node_length=vm_node_length,
                vm_migrated_length=vm_migrated_length,
                bold='',
                end_bold='',
                vm_state_colour=vm_state_colour,
                end_colour=ansiprint.end(),
                vm_name=domain_information['name'],
                vm_uuid=domain_information['uuid'],
                vm_state=domain_information['state'],
                vm_net_colour=vm_net_colour,
                vm_networks=','.join(net_list),
                vm_memory=domain_information['memory'],
                vm_vcpu=domain_information['vcpu'],
                vm_node=domain_information['node'],
                vm_migrated=domain_information['migrated']
            )
        )

    return '\n'.join(sorted(vm_list_output))