Ravada.pm

package Ravada;

use warnings;
use strict;

our $VERSION = '0.2.5';

use Carp qw(carp croak);
use Data::Dumper;
use DBIx::Connector;
use Hash::Util qw(lock_hash);
use Moose;
use POSIX qw(WNOHANG);
use YAML;

use Socket qw( inet_aton inet_ntoa );

use Ravada::Auth;
use Ravada::Request;
use Ravada::VM::KVM;
use Ravada::VM::Void;

=head1 NAME

Ravada - Remove Virtual Desktop Manager

=head1 SYNOPSIS

  use Ravada;

  my $ravada = Ravada->new()

=cut


our $FILE_CONFIG = "/etc/ravada.conf";

###########################################################################

our $CONNECTOR;
our $CONFIG = {};
our $DEBUG;
our $CAN_FORK = 1;
our $CAN_LXC = 0;

# Seconds to wait for other long process
our $SECONDS_WAIT_CHILDREN = 2;
# Limit for long processes
our $LIMIT_PROCESS = 2;
our $LIMIT_HUGE_PROCESS = 1;

our $DIR_SQL = "sql/mysql";
$DIR_SQL = "/usr/share/doc/ravada/sql/mysql" if ! -e $DIR_SQL;

# LONG commands take long
our %HUGE_COMMAND = map { $_ => 1 } qw(download);
our %LONG_COMMAND =  map { $_ => 1 } (qw(prepare_base remove_base screenshot ), keys %HUGE_COMMAND);

our $USER_DAEMON;
our $USER_DAEMON_NAME = 'daemon';

has 'vm' => (
          is => 'ro'
        ,isa => 'ArrayRef'
       ,lazy => 1
     , builder => '_create_vm'
);

has 'connector' => (
        is => 'rw'
);

has 'config' => (
    is => 'ro'
    ,isa => 'Str'
);

has 'warn_error' => (
    is => 'rw'
    ,isa => 'Bool'
    ,default => sub { 1 }
);

=head2 BUILD

Internal constructor

=cut


sub BUILD {
    my $self = shift;
    if ($self->config()) {
        _init_config($self->config);
    } else {
        _init_config($FILE_CONFIG) if -e $FILE_CONFIG;
    }

    if ( $self->connector ) {
        $CONNECTOR = $self->connector
    } else {
        $CONNECTOR = $self->_connect_dbh();
        $self->connector($CONNECTOR);
    }
    Ravada::Auth::init($CONFIG);

    $self->_create_tables();
    $self->_upgrade_tables();
    $self->_init_user_daemon();
    $self->_update_data();
}

sub _init_user_daemon {
    my $self = shift;
    return if $USER_DAEMON;

    $USER_DAEMON = Ravada::Auth::SQL->new(name => $USER_DAEMON_NAME);
    if (!$USER_DAEMON->id) {
        $USER_DAEMON = Ravada::Auth::SQL::add_user(
            name => $USER_DAEMON_NAME,
            is_admin => 1
        );
        $USER_DAEMON = Ravada::Auth::SQL->new(name => $USER_DAEMON_NAME);
    }

}
sub _update_user_grants {
    my $self = shift;
    $self->_init_user_daemon();
    my $sth = $CONNECTOR->dbh->prepare("SELECT id FROM users");
    my $id;
    $sth->execute;
    $sth->bind_columns(\$id);
    while ($sth->fetch) {
        my $user = Ravada::Auth::SQL->search_by_id($id);
        next if $user->name() eq $USER_DAEMON_NAME;

        $USER_DAEMON->grant_user_permissions($user);
        $USER_DAEMON->grant_admin_permissions($user)    if $user->is_admin;
    }
    $sth->finish;
}

sub _update_isos {
    my $self = shift;
    my $table = 'iso_images';
    my $field = 'name';
    my %data = (
        zesty => {
                    name => 'Ubuntu Zesty Zapus'
            ,description => 'Ubuntu 17.04 Zesty Zapus 64 bits'
                   ,arch => 'amd64'
                    ,xml => 'yakkety64-amd64.xml'
             ,xml_volume => 'yakkety64-volume.xml'
                    ,url => 'http://releases.ubuntu.com/17.04/'
                ,file_re => ,'ubuntu-17.04.*desktop-amd64.iso'
                ,md5_url => ,'http://releases.ubuntu.com/17.04/MD5SUMS'
        }
        ,serena64 => {
            name => 'Mint 18.1 Mate 64 bits'
    ,description => 'Mint Serena 18.1 with Mate Desktop based on Ubuntu Xenial 64 bits'
           ,arch => 'amd64'
            ,xml => 'xenial64-amd64.xml'
     ,xml_volume => 'xenial64-volume.xml'
            ,url => 'http://mirrors.evowise.com/linuxmint/stable/18.1/'
        ,file_re => 'linuxmint-18.1-mate-64bit.iso'
        ,md5_url => ''
            ,md5 => 'c5cf5c5d568e2dfeaf705cfa82996d93'

        }

    );

    my $sth_search = $CONNECTOR->dbh->prepare("SELECT id FROM $table WHERE $field = ?");
    for my $name (keys %data) {
        my $row = $data{$name};
        $sth_search->execute($row->{$field});
        my ($id) = $sth_search->fetchrow;
        next if $id;
        warn("INFO: updating $table : $row->{$field}\n")    if $0 !~ /\.t$/;

        my $sql =
            "INSERT INTO iso_images "
            ."("
            .join(" , ", sort keys %{$data{$name}})
            .")"
            ." VALUES ( "
            .join(" , ", map { "?" } keys %{$data{$name}})
            ." )"
        ;
        my $sth = $CONNECTOR->dbh->prepare($sql);
        $sth->execute(map { $data{$name}->{$_} } sort keys %{$data{$name}});
        $sth->finish;
    }
}

sub _update_data {
    my $self = shift;

    $self->_update_isos();
    $self->_update_user_grants();
}

sub _upgrade_table {
    my $self = shift;
    my ($table, $field, $definition) = @_;
    my $dbh = $CONNECTOR->dbh;

    my $sth = $dbh->column_info(undef,undef,$table,$field);
    my $row = $sth->fetchrow_hashref;
    $sth->finish;
    return if $row;

    warn "INFO: adding $field $definition to $table\n"  if $0 !~ /\.t$/;
    $dbh->do("alter table $table add $field $definition");
    return 1;
}

sub _create_table {
    my $self = shift;
    my $table = shift;

    my $sth = $CONNECTOR->dbh->table_info('%',undef,$table,'TABLE');
    my $info = $sth->fetchrow_hashref();
    $sth->finish;
    return if keys %$info;

    warn "INFO: creating table $table\n";
    my $file_sql = "$DIR_SQL/$table.sql";
    open my $in,'<',$file_sql or die "$! $file_sql";
    my $sql = join " ",<$in>;
    close $in;

    $CONNECTOR->dbh->do($sql);
    return 1;
}

sub _insert_data {
    my $self = shift;
    my $table = shift;

    my $file_sql =  "$DIR_SQL/../data/insert_$table.sql";
    return if ! -e $file_sql;

    warn "INFO: inserting data for $table\n";
    open my $in,'<',$file_sql or die "$! $file_sql";
    my $sql = '';
    while (my $line = <$in>) {
        $sql .= $line;
        next if $sql !~ /\w/ || $sql !~ /;\s*$/;
        $CONNECTOR->dbh->do($sql);
        $sql = '';
    }
    close $in;

}

sub _create_tables {
    my $self = shift;
    return if $CONNECTOR->dbh->{Driver}{Name} !~ /mysql/i;

    opendir my $ls,$DIR_SQL or die "$! $DIR_SQL";
    while (my $file = readdir $ls) {
        my ($table) = $file =~ m{(.*)\.sql$};
        next if !$table;
        $self->_insert_data($table)     if $self->_create_table($table);
    }
    closedir $ls;
}

sub _upgrade_tables {
    my $self = shift;
    return if $CONNECTOR->dbh->{Driver}{Name} !~ /mysql/i;

    $self->_upgrade_table('file_base_images','target','varchar(64) DEFAULT NULL');
    $self->_upgrade_table('vms','vm_type',"char(20) NOT NULL DEFAULT 'KVM'");
    $self->_upgrade_table('requests','at_time','int(11) DEFAULT NULL');

    $self->_upgrade_table('iso_images','md5_url','varchar(255)');
    $self->_upgrade_table('iso_images','file_re','char(64)');
    $self->_upgrade_table('iso_images','device','varchar(255)');

    $self->_upgrade_table('users','language','char(3) DEFAULT NULL');
    if ( $self->_upgrade_table('users','is_external','int(11) DEFAULT 0')) {
        my $sth = $CONNECTOR->dbh->prepare(
            "UPDATE users set is_external=1 WHERE password='*LK* no pss'"
        );
        $sth->execute;
    }

    $self->_upgrade_table('networks','requires_password','int(11)');
    $self->_upgrade_table('networks','n_order','int(11) not null default 0');

    $self->_upgrade_table('domains','spice_password','varchar(20) DEFAULT NULL');
}


sub _connect_dbh {
    my $driver= ($CONFIG->{db}->{driver} or 'mysql');;
    my $db_user = ($CONFIG->{db}->{user} or getpwnam($>));;
    my $db_pass = ($CONFIG->{db}->{password} or undef);
    my $db = ( $CONFIG->{db}->{db} or 'ravada' );
    return DBIx::Connector->new("DBI:$driver:$db"
                        ,$db_user,$db_pass,{RaiseError => 1
                        , PrintError=> 0 });

}

=head2 display_ip

Returns the default display IP read from the config file

=cut

sub display_ip {

    my $ip = $CONFIG->{display_ip};

    return $ip if $ip;
}

sub _init_config {
    my $file = shift;

    my $connector = shift;
    confess "Deprecated connector" if $connector;

    $CONFIG = YAML::LoadFile($file);

    $LIMIT_PROCESS = $CONFIG->{limit_process} 
        if $CONFIG->{limit_process} && $CONFIG->{limit_process}>1;
#    $CONNECTOR = ( $connector or _connect_dbh());
}

sub _create_vm_kvm {
    my $self = shift;

    my $cmd_qemu_img = `which qemu-img`;
    chomp $cmd_qemu_img;

    return(undef,"ERROR: Missing qemu-img") if !$cmd_qemu_img;

    my $vm_kvm;

    eval { $vm_kvm = Ravada::VM::KVM->new( connector => ( $self->connector or $CONNECTOR )) };
    my $err_kvm = $@;

    my ($internal_vm , $storage);
    eval {
        $storage = $vm_kvm->dir_img();
        $internal_vm = $vm_kvm->vm;
    };
    $vm_kvm = undef if $@ || !$internal_vm || !$storage;
    $err_kvm .= ($@ or '');
    return ($vm_kvm,$err_kvm);
}

=head2 disconnect_vm

Disconnect all the Virtual Managers connections.

=cut


sub disconnect_vm {
    my $self = shift;
    $self->_disconnect_vm();
}

sub _disconnect_vm{
    my $self = shift;
    return $self->_connect_vm(0);
}

sub _connect_vm {
    my $self = shift;

    my $connect = shift;
    $connect = 1 if !defined $connect;

    my @vms;
    eval { @vms = $self->vm };
    warn $@ if $@ && $self->warn_error;
    return if $@ && $@ =~ /No VMs found/i;
    die $@ if $@;

    return if !scalar @vms;
    for my $n ( 0 .. $#{$self->vm}) {
        my $vm = $self->vm->[$n];

        if (!$connect) {
            $vm->disconnect();
        } else {
            $vm->connect();
        }
    }
}

sub _create_vm {
    my $self = shift;

    my @vms = ();

    my ($vm_kvm, $err_kvm) = $self->_create_vm_kvm();
    warn $err_kvm if $err_kvm && $0 !~ /\.t$/;

    my $err = $err_kvm;

    push @vms,($vm_kvm) if $vm_kvm;

    my $vm_lxc;
    if ($CAN_LXC) {
        eval { $vm_lxc = Ravada::VM::LXC->new( connector => ( $self->connector or $CONNECTOR )) };
        push @vms,($vm_lxc) if $vm_lxc;
        my $err_lxc = $@;
        $err .= "\n$err_lxc" if $err_lxc;
    }
    if (!@vms) {
        warn "No VMs found: $err\n" if $self->warn_error;
    }
    return \@vms;

}

sub _check_vms {
    my $self = shift;

    my @vm;
    eval { @vm = @{$self->vm} };
    for my $n ( 0 .. $#vm ) {
        if ($vm[$n] && ref $vm[$n] =~ /KVM/i) {
            if (!$vm[$n]->is_alive) {
                warn "$vm[$n] dead" if $DEBUG;
                $vm[$n] = $self->_create_vm_kvm();
            }
        }
    }
}

=head2 create_domain

Creates a new domain based on an ISO image or another domain.

  my $domain = $ravada->create_domain(
         name => $name
    , id_iso => 1
  );


  my $domain = $ravada->create_domain(
         name => $name
    , id_base => 3
  );


=cut


sub create_domain {
    my $self = shift;

    my %args = @_;

    croak "Argument id_owner required "
        if !$args{id_owner};

    my $vm_name = $args{vm};
    delete $args{vm};

    my $request = ( $args{request} or undef);

    my $vm;
    if ($vm_name) {
        $vm = $self->search_vm($vm_name);
        confess "ERROR: vm $vm_name not found"  if !$vm;
    }
    $vm = $self->vm->[0]               if !$vm;

    confess "No vm found"   if !$vm;

    carp "WARNING: no VM defined, we will use ".$vm->name
        if !$vm_name;

    confess "I can't find any vm ".Dumper($self->vm) if !$vm;

    return $vm->create_domain(@_);
}

=head2 remove_domain

Removes a domain

  $ravada->remove_domain($name);

=cut

sub remove_domain {
    my $self = shift;
    my %arg = @_;

    confess "Argument name required "
        if !$arg{name};

    confess "Argument uid required "
        if !$arg{uid};

    lock_hash(%arg);

    my $domain = $self->search_domain($arg{name}, 1)
        or die "ERROR: I can't find domain '$arg{name}', maybe already removed.";

    my $user = Ravada::Auth::SQL->search_by_id( $arg{uid});
    $domain->remove( $user);
}

=head2 search_domain

  my $domain = $ravada->search_domain($name);

=cut

sub search_domain {
    my $self = shift;
    my $name = shift;
    my $import = shift;

    my $vm = $self->search_vm('Void');
    warn "No Void VM" if !$vm;
    return if !$vm;

    my $domain = $vm->search_domain($name, $import);
    return $domain if $domain;

    my @vms;
    eval { @vms = $self->vm };
    return if $@ && $@ =~ /No VMs found/i;
    die $@ if $@;

    for my $vm (@{$self->vm}) {
        my $domain = $vm->search_domain($name, $import);
        next if !$domain;
        next if !$domain->_select_domain_db && !$import;
        my $id;
        eval { $id = $domain->id };
        # TODO import the domain in the database with an _insert_db or something
        warn $@ if $@   && $DEBUG;
        return $domain if $id || $import;
    }


    return;
}

=head2 search_domain_by_id

  my $domain = $ravada->search_domain_by_id($id);

=cut

sub search_domain_by_id {
    my $self = shift;
    my $id = shift  or confess "ERROR: missing argument id";

    my $sth = $CONNECTOR->dbh->prepare("SELECT name FROM domains WHERE id=?");
    $sth->execute($id);
    my ($name) = $sth->fetchrow;
    confess "Unknown domain id=$id" if !$name;

    return $self->search_domain($name);
}

=head2 list_domains

List all created domains

  my @list = $ravada->list_domains();

=cut

sub list_domains {
    my $self = shift;
    my @domains;
    for my $vm (@{$self->vm}) {
        for my $domain ($vm->list_domains) {
            push @domains,($domain);
        }
    }
    return @domains;
}

=head2 list_domains_data

List all domains in raw format. Return a list of id => { name , id , is_active , is_base }

   my $list = $ravada->list_domains_data();

   $c->render(json => $list);

=cut

sub list_domains_data {
    my $self = shift;
    my @domains;
    my $sth = $CONNECTOR->dbh->prepare(
        "SELECT * FROM domains ORDER BY name"
    );
    $sth->execute;
    while (my $row = $sth->fetchrow_hashref) {
        push @domains,($row);
    }
    $sth->finish;
    return \@domains;
}

# sub list_domains_data {
#     my $self = shift;
#     my @domains;
#     for my $domain ($self->list_domains()) {
#         eval { $domain->id };
#         warn $@ if $@;
#         next if $@;
#         push @domains, {                id => $domain->id
#                                     , name => $domain->name
#                                   ,is_base => $domain->is_base
#                                 ,is_active => $domain->is_active

#                            }
#     }
#     return \@domains;
# }


=head2 list_bases

List all base domains

  my @list = $ravada->list_domains();


=cut

sub list_bases {
    my $self = shift;
    my @domains;
    for my $vm (@{$self->vm}) {
        for my $domain ($vm->list_domains) {
            eval { $domain->id };
            warn $@ if $@;
            next    if $@;
            push @domains,($domain) if $domain->is_base;
        }
    }
    return @domains;
}

=head2 list_bases_data

List information about the bases

=cut

sub list_bases_data {
    my $self = shift;
    my @data;
    for ($self->list_bases ) {
        push @data,{ id => $_->id , name => $_->name };
    }
    return \@data;
}

=head2 list_images

List all ISO images

=cut

sub list_images {
    my $self = shift;
    my @domains;
    my $sth = $CONNECTOR->dbh->prepare(
        "SELECT * FROM iso_images ORDER BY name"
    );
    $sth->execute;
    while (my $row = $sth->fetchrow_hashref) {
        push @domains,($row);
    }
    $sth->finish;
    return @domains;
}

=head2 list_images_data

List information about the images

=cut

sub list_images_data {
    my $self = shift;
    my @data;
    for ($self->list_images ) {
        push @data,{ id => $_->{id} , name => $_->{name} };
    }
    return \@data;
}


=pod

sub _list_images_lxc {
    my $self = shift;
    my @domains;
    my $sth = $CONNECTOR->dbh->prepare(
        "SELECT * FROM lxc_templates ORDER BY name"
    );
    $sth->execute;
    while (my $row = $sth->fetchrow_hashref) {
        push @domains,($row);
    }
    $sth->finish;
    return @domains;
}

sub _list_images_data_lxc {
    my $self = shift;
    my @data;
    for ($self->list_images_lxc ) {
        push @data,{ id => $_->{id} , name => $_->{name} };
    }
    return \@data;
}

=cut

=head2 remove_volume

  $ravada->remove_volume($file);


=cut

sub remove_volume {
    my $self = shift;

    my $file = shift;
    my ($name) = $file =~ m{.*/(.*)};

    my $removed = 0;
    for my $vm (@{$self->vm}) {
        my $vol = $vm->search_volume($name);
        next if !$vol;

        $vol->delete();
        $removed++;
    }
    if (!$removed && -e $file ) {
        warn "volume $file not found. removing file $file.\n";
        unlink $file or die "$! $file";
    }

}

=head2 clean_killed_requests

Before processing requests, old killed requests must be cleaned.

=cut

sub clean_killed_requests {
    my $self = shift;
    my $sth = $CONNECTOR->dbh->prepare("SELECT id FROM requests "
        ." WHERE status <> 'done' AND STATUS <> 'requested'"
    );
    $sth->execute;
    while (my ($id) = $sth->fetchrow) {
        my $req = Ravada::Request->open($id);
        $req->status("done","Killed ".$req->command." before completion");
    }

}

=head2 process_requests

This is run in the ravada backend. It processes the commands requested by the fronted

  $ravada->process_requests();

=cut

sub process_requests {
    my $self = shift;
    my $debug = shift;
    my $dont_fork = shift;
    my $long_commands = (shift or 0);
    my $short_commands = (shift or 0);

    $self->_wait_pids_nohang();

    my $sth = $CONNECTOR->dbh->prepare("SELECT id,id_domain FROM requests "
        ." WHERE "
        ."    ( status='requested' OR status like 'retry %' OR status='waiting')"
        ."   AND ( at_time IS NULL  OR at_time = 0 OR at_time<=?) "
        ." ORDER BY date_req"
    );
    $sth->execute(time);

    my $debug_type = '';
    $debug_type = 'long' if $long_commands;
    $debug_type = 'short' if $short_commands || !$long_commands;
    $debug_type = 'all' if $long_commands && $short_commands;

    while (my ($id_request,$id_domain)= $sth->fetchrow) {
        my $req = Ravada::Request->open($id_request);

        if ( ($long_commands && 
                (!$short_commands && !$LONG_COMMAND{$req->command}))
            ||(!$long_commands && $LONG_COMMAND{$req->command})
        ) {
            warn "[$debug_type,$long_commands,$short_commands] $$ skipping request "
                .$req->command  if $DEBUG;
            next;
        }
        next if $req->command !~ /shutdown/i
            && $self->_domain_working($id_domain, $id_request);

        warn "[$debug_type] $$ executing request ".$req->id." ".$req->status()." "
            .$req->command
            ." ".Dumper($req->args) if $DEBUG || $debug;

        my ($n_retry) = $req->status() =~ /retry (\d+)/;
        $n_retry = 0 if !$n_retry;
        my $err = $self->_execute($req, $dont_fork);
        $req->error($err)   if $err;
        if ($err && $err =~ /libvirt error code: 38/) {
            if ( $n_retry < 3) {
                warn $req->id." ".$req->command." to retry" if $DEBUG;
                $req->status("retry ".++$n_retry)
            }
        }
        next if !$DEBUG && !$debug;

        sleep 1;
        warn "req ".$req->id." , command: ".$req->command." , status: ".$req->status()
            ." , error: '".($req->error or 'NONE')."'\n"  if $DEBUG;

    }
    $sth->finish;

}

=head2 process_long_requests

Process requests that take log time. It will fork on each one

=cut

sub process_long_requests {
    my $self = shift;
    my ($debug,$dont_fork) = @_;

    $self->_disconnect_vm();
    return $self->process_requests($debug, $dont_fork, 1);
}

=head2 process_all_requests

Process all the requests, long and short

=cut

sub process_all_requests {

    my $self = shift;
    my ($debug,$dont_fork) = @_;

    $self->process_requests($debug, $dont_fork,1,1);

}

sub _domain_working {
    my $self = shift;
    my ($id_domain, $id_request) = @_;

    confess "Missing id_request" if !defined$id_request;

    if (!$id_domain) {
        my $req = Ravada::Request->open($id_request);
        $id_domain = $req->defined_arg('id_base');
        if (!$id_domain) {
            my $domain_name = $req->defined_arg('name');
            return if !$domain_name;
            my $domain = $self->search_domain($domain_name) or return;
            $id_domain = $domain->id;
            if (!$id_domain) {
                warn Dumper($req);
                return;
            }
        }
    }
    my $sth = $CONNECTOR->dbh->prepare("SELECT id, status FROM requests "
        ." WHERE id <> ? AND id_domain=? AND (status <> 'requested' AND status <> 'done')");
    $sth->execute($id_request, $id_domain);
    my ($id, $status) = $sth->fetchrow;
#    warn "CHECKING DOMAIN WORKING "
#        ."[$id_request] id_domain $id_domain working in request ".($id or '<NULL>')
#            ." status: ".($status or '<UNDEF>');
    return $id;
}

sub _process_all_requests_dont_fork {
    my $self = shift;
    my $debug = shift;

    return $self->process_requests($debug,1, 1, 1);
}

sub _process_requests_dont_fork {
    my $self = shift;
    my $debug = shift;
    return $self->process_requests($debug, 1);
}

=head2 list_vm_types

Returnsa list ofthe types of Virtual Machines available on this system

=cut

sub list_vm_types {
    my $self = shift;

    my %type;
    for my $vm (@{$self->vm}) {
            my ($name) = ref($vm) =~ /.*::(.*)/;
            $type{$name}++;
    }
    return keys %type;
}

sub _execute {
    my $self = shift;
    my $request = shift;
    my $dont_fork = shift;

    my $sub = $self->_req_method($request->command);

    confess "Unknown command ".$request->command
            if !$sub;

    if ($dont_fork || !$CAN_FORK || !$LONG_COMMAND{$request->command}) {

        eval { $sub->($self,$request) };
        my $err = ($@ or '');
        $request->error($err);
        $request->status('done') if $request->status() ne 'done';
        return $err;
    }

    $self->_wait_pids_nohang();
    return if $self->_wait_children($request);

    $request->status('working');
    my $pid = fork();
    die "I can't fork" if !defined $pid;
    if ( $pid == 0 ) {
        $self->_do_execute_command($sub, $request) 
    } else {
        $self->_add_pid($pid, $request->id);
    }
#    $self->_connect_vm_kvm();
    return '';
}

sub _do_execute_command {
    my $self = shift;
    my ($sub, $request) = @_;

#    if ($DEBUG ) {
#        mkdir 'log' if ! -e 'log';
#        open my $f_out ,'>', "log/fork_$$.out";
#        open my $f_err ,'>', "log/fork_$$.err";
#        $| = 1;
#        local *STDOUT = $f_out;
#        local *STDERR = $f_err;
#    }

    eval {
        $self->_connect_vm();
        $sub->($self,$request);
        $self->_disconnect_vm();
    };
    my $err = ( $@ or '');
    $request->error($err);
    $request->status('done') if $request->status() ne 'done';
    exit;

}

sub _cmd_domdisplay {
    my $self = shift;
    my $request = shift;