Feature maintenance mode (#1331)

feature(fontend): maintenance mode

closes issue #1331

Makefile.PL

@@ -31,6 +31,7 @@ WriteMakefile(
     ,'Net::DNS' => 0
     ,'Net::SSH2' => 0
     ,'File::Rsync' => 0
+    ,'DateTime::Format::DateParse'=> 0
   },
   BUILD_REQUIRES => {
     'Test::Perl::Critic' => 0

debian/control-debian-10

@@ -4,7 +4,7 @@ Architecture: all
 Section: utils
 Priority: optional
 Maintainer: Francesc Guasch <frankie@telecos.upc.edu>
-Depends: perl (>=5.18),libmojolicious-perl,mysql-common,libauthen-passphrase-perl, libdatetime-perl, libdbd-mysql-perl,libdbi-perl,libdbix-connector-perl,libipc-run3-perl,libio-stringy-perl,libnet-ldap-perl,libproc-pid-file-perl,libvirt-daemon-system,libsys-virt-perl,libxml-libxml-perl,libconfig-yaml-perl,libmoose-perl,libjson-xs-perl,qemu-utils,perlmagick,libmoosex-types-netaddr-ip-perl,libio-interface-perl,libiptables-chainmgr-perl,libnet-dns-perl,wget,liblocale-maketext-lexicon-perl,libmojolicious-plugin-i18n-perl,libdbd-sqlite3-perl, debconf (>= 0.2.26), adduser, libdigest-sha-perl, qemu-kvm, net-tools, libfile-rsync-perl, libnet-ssh2-perl, bridge-utils, libencode-locale-perl, libpbkdf2-tiny-perl
+Depends: perl (>=5.18),libmojolicious-perl,mysql-common,libauthen-passphrase-perl, libdatetime-perl, libdbd-mysql-perl,libdbi-perl,libdbix-connector-perl,libipc-run3-perl,libio-stringy-perl,libnet-ldap-perl,libproc-pid-file-perl,libvirt-daemon-system,libsys-virt-perl,libxml-libxml-perl,libconfig-yaml-perl,libmoose-perl,libjson-xs-perl,qemu-utils,perlmagick,libmoosex-types-netaddr-ip-perl,libio-interface-perl,libiptables-chainmgr-perl,libnet-dns-perl,wget,liblocale-maketext-lexicon-perl,libmojolicious-plugin-i18n-perl,libdbd-sqlite3-perl, debconf (>= 0.2.26), adduser, libdigest-sha-perl, qemu-kvm, net-tools, libfile-rsync-perl, libnet-ssh2-perl, bridge-utils, libencode-locale-perl, libpbkdf2-tiny-perl, libdatetime-format-dateparse-perl
 Description: Remote Virtual Desktops Manager
  Ravada is a software that allows the user to connect to a
  remote virtual desktop.

debian/control-ubuntu-18.04

@@ -4,7 +4,7 @@ Architecture: all
 Section: utils
 Priority: optional
 Maintainer: Francesc Guasch <frankie@telecos.upc.edu>
-Depends: perl (>=5.18),libmojolicious-perl,mysql-common,libauthen-passphrase-perl, libdatetime-perl, libdbd-mysql-perl,libdbi-perl,libdbix-connector-perl,libipc-run3-perl,libio-stringy-perl,libnet-ldap-perl,libproc-pid-file-perl,libvirt-bin,libvirt-daemon-system,libsys-virt-perl,libxml-libxml-perl,libconfig-yaml-perl,libmoose-perl,libjson-xs-perl,qemu-utils,perlmagick,libmoosex-types-netaddr-ip-perl,libio-interface-perl,libiptables-chainmgr-perl,libnet-dns-perl,wget,liblocale-maketext-lexicon-perl,libmojolicious-plugin-i18n-perl,libdbd-sqlite3-perl, debconf (>= 0.2.26), adduser, libdigest-sha-perl, qemu-kvm, net-tools, libfile-rsync-perl, libnet-ssh2-perl, bridge-utils, libencode-locale-perl, libpbkdf2-tiny-perl
+Depends: perl (>=5.18),libmojolicious-perl,mysql-common,libauthen-passphrase-perl, libdatetime-perl, libdbd-mysql-perl,libdbi-perl,libdbix-connector-perl,libipc-run3-perl,libio-stringy-perl,libnet-ldap-perl,libproc-pid-file-perl,libvirt-bin,libvirt-daemon-system,libsys-virt-perl,libxml-libxml-perl,libconfig-yaml-perl,libmoose-perl,libjson-xs-perl,qemu-utils,perlmagick,libmoosex-types-netaddr-ip-perl,libio-interface-perl,libiptables-chainmgr-perl,libnet-dns-perl,wget,liblocale-maketext-lexicon-perl,libmojolicious-plugin-i18n-perl,libdbd-sqlite3-perl, debconf (>= 0.2.26), adduser, libdigest-sha-perl, qemu-kvm, net-tools, libfile-rsync-perl, libnet-ssh2-perl, bridge-utils, libencode-locale-perl, libpbkdf2-tiny-perl, libdatetime-format-dateparse-perl
 Description: Remote Virtual Desktops Manager
  Ravada is a software that allows the user to connect to a
  remote virtual desktop.

debian/control-ubuntu-19.04

@@ -4,7 +4,7 @@ Architecture: all
 Section: utils
 Priority: optional
 Maintainer: Francesc Guasch <frankie@telecos.upc.edu>
-Depends: perl (>=5.18),libmojolicious-perl,mysql-common,libauthen-passphrase-perl, libdatetime-perl, libdbd-mysql-perl,libdbi-perl,libdbix-connector-perl,libipc-run3-perl,libio-stringy-perl,libnet-ldap-perl,libproc-pid-file-perl,libvirt-daemon-system,libsys-virt-perl,libxml-libxml-perl,libconfig-yaml-perl,libmoose-perl,libjson-xs-perl,qemu-utils,perlmagick,libmoosex-types-netaddr-ip-perl,libio-interface-perl,libiptables-chainmgr-perl,libnet-dns-perl,wget,liblocale-maketext-lexicon-perl,libmojolicious-plugin-i18n-perl,libdbd-sqlite3-perl, debconf (>= 0.2.26), adduser, libdigest-sha-perl, qemu-kvm, net-tools, libfile-rsync-perl, libnet-ssh2-perl, bridge-utils, libpbkdf2-tiny-perl
+Depends: perl (>=5.18),libmojolicious-perl,mysql-common,libauthen-passphrase-perl, libdatetime-perl, libdbd-mysql-perl,libdbi-perl,libdbix-connector-perl,libipc-run3-perl,libio-stringy-perl,libnet-ldap-perl,libproc-pid-file-perl,libvirt-daemon-system,libsys-virt-perl,libxml-libxml-perl,libconfig-yaml-perl,libmoose-perl,libjson-xs-perl,qemu-utils,perlmagick,libmoosex-types-netaddr-ip-perl,libio-interface-perl,libiptables-chainmgr-perl,libnet-dns-perl,wget,liblocale-maketext-lexicon-perl,libmojolicious-plugin-i18n-perl,libdbd-sqlite3-perl, debconf (>= 0.2.26), adduser, libdigest-sha-perl, qemu-kvm, net-tools, libfile-rsync-perl, libnet-ssh2-perl, bridge-utils, libpbkdf2-tiny-perl, libdatetime-format-dateparse-perl
 Description: Remote Virtual Desktops Manager
  Ravada is a software that allows the user to connect to a
  remote virtual desktop.

debian/control-ubuntu-20.04

@@ -4,7 +4,7 @@ Architecture: all
 Section: utils
 Priority: optional
 Maintainer: Francesc Guasch <frankie@telecos.upc.edu>
-Depends: perl (>=5.18),libmojolicious-perl,mysql-common,libauthen-passphrase-perl, libdatetime-perl, libdbd-mysql-perl,libdbi-perl,libdbix-connector-perl,libipc-run3-perl,libio-stringy-perl,libnet-ldap-perl,libproc-pid-file-perl,libvirt-daemon-system,libsys-virt-perl,libxml-libxml-perl,libconfig-yaml-perl,libmoose-perl,libjson-xs-perl,qemu-utils,perlmagick,libmoosex-types-netaddr-ip-perl,libio-interface-perl,libiptables-chainmgr-perl,libnet-dns-perl,wget,liblocale-maketext-lexicon-perl,libmojolicious-plugin-i18n-perl,libdbd-sqlite3-perl, debconf (>= 0.2.26), adduser, libdigest-sha-perl, qemu-kvm, net-tools, libfile-rsync-perl, libnet-ssh2-perl, bridge-utils, libpbkdf2-tiny-perl
+Depends: perl (>=5.18),libmojolicious-perl,mysql-common,libauthen-passphrase-perl, libdatetime-perl, libdbd-mysql-perl,libdbi-perl,libdbix-connector-perl,libipc-run3-perl,libio-stringy-perl,libnet-ldap-perl,libproc-pid-file-perl,libvirt-daemon-system,libsys-virt-perl,libxml-libxml-perl,libconfig-yaml-perl,libmoose-perl,libjson-xs-perl,qemu-utils,perlmagick,libmoosex-types-netaddr-ip-perl,libio-interface-perl,libiptables-chainmgr-perl,libnet-dns-perl,wget,liblocale-maketext-lexicon-perl,libmojolicious-plugin-i18n-perl,libdbd-sqlite3-perl, debconf (>= 0.2.26), adduser, libdigest-sha-perl, qemu-kvm, net-tools, libfile-rsync-perl, libnet-ssh2-perl, bridge-utils, libpbkdf2-tiny-perl, libdatetime-format-dateparse-perl
 Description: Remote Virtual Desktops Manager
  Ravada is a software that allows the user to connect to a
  remote virtual desktop.

lib/Ravada.pm

@@ -138,11 +138,13 @@ sub BUILD {
 }
 
 sub _install($self) {
+    $self->_sql_create_tables();
     $self->_create_tables();
     $self->_upgrade_tables();
     $self->_upgrade_timestamps();
     $self->_update_data();
     $self->_init_user_daemon();
+    $self->_sql_insert_defaults();
 }
 
 sub _init_user_daemon {
@@ -897,6 +899,9 @@ sub _add_indexes_generic($self) {
              "index(id_request,date_send)"
              ,"index(date_changed)"
         ]
+        ,settings => [
+            "index(id_parent,name)"
+        ]
     );
     for my $table ( keys %index ) {
         my $known = $self->_get_indexes($table);
@@ -906,7 +911,7 @@ sub _add_indexes_generic($self) {
             $name =~ s/,/_/g;
             next if $known->{$name};
             my $sql = "ALTER TABLE $table add $type $name ($fields)";
-            warn "INFO: Adding index to vms: $name";
+            warn "INFO: Adding index to $table: $name";
             my $sth = $CONNECTOR->dbh->prepare($sql);
             $sth->execute();
         }
@@ -1286,6 +1291,124 @@ sub _create_tables {
     closedir $ls;
 }
 
+sub _sql_create_tables($self) {
+    my $driver = lc($CONNECTOR->dbh->{Driver}{Name});
+    my %tables = (
+        settings => {
+            id => 'integer NOT NULL PRIMARY KEY AUTO_INCREMENT'
+            , id_parent => 'INT NOT NULL'
+            , name => 'varchar(64) NOT NULL'
+            , value => 'varchar(128) DEFAULT NULL'
+        }
+    );
+    for my $table ( keys %tables ) {
+        my $sth = $CONNECTOR->dbh->table_info('%',undef,$table,'TABLE');
+        my $info = $sth->fetchrow_hashref();
+        $sth->finish;
+        next if keys %$info;
+
+        warn "INFO: creating table $table\n"    if $0 !~ /\.t$/;
+
+        my $sql_fields;
+        for my $field (sort keys %{$tables{$table}} ) {
+            my $definition = _port_definition($driver, $tables{$table}->{$field});
+            $sql_fields .= ", " if $sql_fields;
+            $sql_fields .= " $field $definition";
+        }
+
+        my $sql = "CREATE TABLE $table ( $sql_fields )";
+        $CONNECTOR->dbh->do($sql);
+
+    }
+}
+
+sub _sql_insert_defaults($self){
+    my $cont = 1;
+    require Mojolicious::Plugin::Config;
+    my $plugin = Mojolicious::Plugin::Config->new();
+    my $conf = $plugin->load("/etc/rvd_front.conf");
+    my %values = (
+        settings => [
+            {
+                id => $cont++
+                ,id_parent => 0
+                ,name => 'frontend'
+            }
+            ,{  id => $cont++
+                ,id_parent => 1
+                ,name => 'fallback'
+                ,value => $conf->{fallback}
+            }
+            ,{  id => $cont++
+                ,id_parent => 1
+                ,name => 'maintenance'
+                ,value => 0
+            }
+            ,{  id => $cont++
+                ,id_parent => 1
+                ,name => 'maintenance_start'
+                ,value => ''
+            }
+            ,{  id => $cont++
+                ,id_parent => 1
+                ,name => 'maintenance_end'
+                ,value => ''
+            }
+
+            ,{  id => $cont++
+                ,id_parent => 1
+                ,name => 'session_timeout'
+                ,value => $conf->{session_timeout}
+            }
+            ,{  id => $cont++
+                ,id_parent => 1
+                ,name => 'session_timeout_admin'
+                ,value => $conf->{session_timeout_admin}
+            }
+            ,{  id => $cont++
+                ,id_parent => 1
+                ,name => 'auto_view'
+                ,value => $conf->{auto_view}
+            }
+        ]
+    );
+
+    for my $table (sort keys %values) {
+        my $sth = $CONNECTOR->dbh->prepare("SELECT id FROM $table "
+            ." WHERE id = ? "
+        );
+        for my $entry (@{$values{$table}}) {
+            $sth->execute($entry->{id});
+            my ($found) = $sth->fetchrow;
+            next if $found;
+            warn "INFO adding default $table ".Dumper($entry) if $0 !~ /t$/;
+            $self->_sql_insert_values($table, $entry);
+        }
+    }
+}
+
+sub _sql_insert_values($self, $table, $entry) {
+    my $sql = "INSERT INTO $table "
+    ."( "
+        .join(" , ",sort keys %$entry)
+    .") "
+    ." VALUES ( "
+        .join(" , ", map { '? ' } keys %$entry)
+    ." ) ";
+
+    my $sth = $CONNECTOR->dbh->prepare($sql);
+    $sth->execute(map { $entry->{$_} } sort keys %$entry);
+
+}
+
+sub _port_definition($driver, $definition0){
+    return $definition0 if $driver eq 'mysql';
+    if ($driver eq 'sqlite') {
+        $definition0 =~ s/(.*) AUTO_INCREMENT$/$1 AUTOINCREMENT/i;
+        return $definition0 if $definition0 =~ /^(int|integer|char|varchar) /i;
+    }
+}
+
 sub _clean_iso_mini {
     my $sth = $CONNECTOR->dbh->prepare("DELETE FROM iso_images WHERE device like ?");
     $sth->execute('%/mini.iso');

lib/Ravada/Front.pm

@@ -11,6 +11,7 @@ Ravada::Front - Web Frontend library for Ravada
 
 use Carp qw(carp);
 use DateTime;
+use DateTime::Format::DateParse;
 use Hash::Util qw(lock_hash);
 use IPC::Run3 qw(run3);
 use JSON::XS;
@@ -1204,6 +1205,51 @@ sub _dbh {
     return $CONNECTOR->dbh;
 }
 
+sub _get_settings($self, $id_parent=0) {
+    my $sth = $CONNECTOR->dbh->prepare(
+        "SELECT id,name,value"
+        ." FROM settings "
+        ." WHERE id_parent= ? "
+    );
+    $sth->execute($id_parent);
+    my $ret;
+    while ( my ( $id, $name, $value) = $sth->fetchrow) {
+        $value = 0+$value if defined $value && $value =~ /^\d+$/;
+        my $setting_sons = $self->_get_settings($id);
+        if ($setting_sons) {
+            $ret->{$name} = $setting_sons;
+        } else {
+            $ret->{$name} = { id => $id, value => $value};
+        }
+    }
+    return $ret;
+}
+
+sub settings_global($self) {
+    return $self->_get_settings();
+}
+
+sub is_in_maintenance($self) {
+    my $settings = $self->settings_global();
+    return 0 if ! $settings->{frontend}->{maintenance}->{value};
+
+    my $start = DateTime::Format::DateParse->parse_datetime(
+        $settings->{frontend}->{maintenance_start}->{value});
+    my $end= DateTime::Format::DateParse->parse_datetime(
+        $settings->{frontend}->{maintenance_end}->{value});
+    my $now = DateTime->now();
+
+    if ( $now >= $start && $now <= $end ) {
+        return 1;
+    }
+    my $sth = $self->_dbh->prepare("UPDATE settings set value = 0 "
+        ." WHERE id=? "
+    );
+    $sth->execute($settings->{frontend}->{maintenance}->{id});
+
+    return 0;
+}
+
 =head2 version
 
 Returns the version of the main module

public/js/admin.js

@@ -8,6 +8,7 @@ ravadaApp.directive("solShowMachine", swMach)
         .controller("messagesPage", messagesPageC)
         .controller("manage_nodes",manage_nodes)
         .controller("new_node", newNodeCtrl)
+        .controller("settings_global", settings_global_ctrl)
     ;
 
     ravadaApp.filter('orderObjectBy', function() {
@@ -510,4 +511,41 @@ ravadaApp.directive("solShowMachine", swMach)
             });
         };
     };
+
+    function settings_global_ctrl($scope, $http) {
+        $scope.init = function() {
+            $http.get('/settings_global.json').then(function(response) {
+                $scope.settings = response.data;
+                var now = new Date();
+                if ($scope.settings.frontend.maintenance.value == 0 ) {
+                    console.log("default");
+                    $scope.settings.frontend.maintenance_start.value
+                        = new Date(now.getFullYear(), now.getMonth(), now.getDate()
+                            , now.getHours(), now.getMinutes());
+
+                    $scope.settings.frontend.maintenance_end.value
+                        = new Date(now.getFullYear(), now.getMonth(), now.getDate()
+                            , now.getHours(), now.getMinutes() + 15);
+                } else {
+                    $scope.settings.frontend.maintenance_start.value
+                    =new Date($scope.settings.frontend.maintenance_start.value);
+
+                    $scope.settings.frontend.maintenance_end.value
+                    =new Date($scope.settings.frontend.maintenance_end.value);
+                }
+            });
+        };
+        $scope.load_settings = function() {
+            $scope.init();
+            $scope.formSettings.$setPristine();
+        };
+        $scope.update_settings = function() {
+            $scope.formSettings.$setPristine();
+            console.log($scope.settings);
+            $http.post('/settings_global'
+                ,JSON.stringify($scope.settings)
+            ).then(function(response) {
+            });
+        };
+    };
 }());

public/js/ravada.js

@@ -27,6 +27,7 @@
             .controller("users", usersCrtl)
             .controller("bases", mainpageCrtl)
             .controller("singleMachinePage", singleMachinePageC)
+            .controller("maintenance",maintenanceCtrl)
             .controller("notifCrtl", notifCrtl)
             .controller("run_domain",run_domain_ctrl)
             .controller("run_domain_req",run_domain_req_ctrl)
@@ -976,6 +977,12 @@
 
   };
 
+    function maintenanceCtrl($scope, $interval, $http, request){
+        $scope.init = function(end) {
+            $scope.maintenance_end = new Date(end);
+        };
+    };
+
 /*
   function requestsCrtlSingle($scope, $interval, $http, request){
     $scope.getReqs= function() {

script/rvd_front

@@ -99,7 +99,6 @@ setlocale(LC_CTYPE, $old_locale);
 #####
 #####
 plugin I18N => {namespace => 'Ravada::I18N', default => 'en'};
-plugin 'RenderFile';
 
 my %config;
 %config = (config => $CONFIG_FRONT->{config}) if $CONFIG_FRONT->{config};
@@ -147,12 +146,20 @@ hook before_routes => sub {
             ,host => $host
             );
 
-    return if _logged_in($c);
-    return if $url =~ m{^/(anonymous|login|logout|requirements|robots.txt)}
-           || $url =~ m{^/(css|font|img|js)}
+    $USER = _logged_in($c);
+
+    return if $url =~ m{^/(css|font|img|js)}
 	   || $url =~ m{^/fallback/.*\.(css|js|map)$};
 
-    # anonymous URLs
+    return if $url =~ m{^/(login|logout|requirements|robots.txt)};
+
+    if ( $RAVADA->is_in_maintenance ) {
+        return login($c) if !$USER && $url =~ m{^/$};
+        return maintenance($c) if !$USER || !$USER->is_operator;
+    }
+
+    return if $url =~ m{^/anonymous};
+
     if (($url =~ m{^/machine/(clone|display|info|view)/}
         || $url =~ m{^/(list_bases_anonymous|request/)}i
         || $url =~ m{^/ws/subscribe}
@@ -244,6 +251,26 @@ get '/anonymous/(#base_id).html' => sub {
     return quick_start_domain($c,$base->id, $USER->name);
 };
 
+get '/settings_global.json' => sub($c) {
+    $RAVADA->is_in_maintenance();
+    return $c->render(json => $RAVADA->settings_global );
+};
+
+post '/settings_global' => sub($c) {
+    my $arg = decode_json($c->req->body);
+
+    my $orig_settings;
+    my $sth = $RAVADA->_dbh->prepare("SELECT id,value FROM settings");
+    $sth->execute();
+    while (my ($id, $value) = $sth->fetchrow) {
+        $orig_settings->{$id} = $value;
+    }
+
+    _update_settings($arg, $orig_settings);
+
+    return $c->render(json => { ok => 1 });
+};
+
 any '/admin/#type' => sub {
   my $c = shift;
 
@@ -1375,6 +1402,7 @@ get '/iso/download/(#id).json' => sub {
 websocket '/ws/subscribe' => sub {
     my $c = shift;
     my $expiration = $SESSION_TIMEOUT;
+    return if !$USER;
     $expiration = $SESSION_TIMEOUT_ADMIN    if $USER->is_admin;
     $c->inactivity_timeout( $expiration );
     $c->on(message => sub {
@@ -1493,7 +1521,13 @@ sub login {
             );
 
             $auth_ok = Ravada::Auth::SQL->new(name => $auth_ok->name);
+            if ( $RAVADA->is_in_maintenance() ) {
+                return maintenance($c) unless $auth_ok->is_operator;
+                $auth_ok->send_message('Warning: Server under maintenance. <a href="/admin/settings">Settings</a>');
+            }
+
             my $machines = $RAVADA->list_machines_user($auth_ok);
+
             $url = "/machine/clone/". $machines->[0]->{id}.".html" if scalar(@$machines) == 1 && !($auth_ok->is_admin);
             my $auto_view = 1;
 
@@ -1650,6 +1684,11 @@ sub admin {
     if ($page eq 'nodes') {
         Ravada::Request->refresh_vms();
     }
+    if ($page eq 'settings') {
+        my $url = $c->req->url->to_abs->path;
+        my $host = $c->req->url->to_abs->host;
+        $c->stash(url_login => "/login");
+    }
     $c->render( template => 'main/admin_'.$page);
 };
 
@@ -2462,6 +2501,41 @@ sub _new_anonymous_user {
     return $name;
 }
 
+sub _update_settings($arg, $orig_settings) {
+    for my $field (keys %$arg) {
+        if ( !exists $arg->{$field}->{id} ) {
+            _update_settings($arg->{$field}, $orig_settings);
+            next;
+        }
+        confess "Error: invalid field $field" if $field !~ /^\w+$/;
+        my ( $value, $id )
+                   = ($arg->{$field}->{value}
+                    , $arg->{$field}->{id}
+        );
+        next if $orig_settings->{$id} eq $value;
+        my $sth = $RAVADA->_dbh->prepare(
+            "UPDATE settings set value=?"
+            ." WHERE id=? "
+        );
+        $sth->execute($value, $id);
+
+        $USER->send_message("Setting $field to $value");
+    }
+};
+
+sub maintenance($c) {
+
+    my $maintenance_end = $RAVADA->settings_global->{frontend}->{maintenance_end}
+                                                            ->{value};
+    my $localtime_end = DateTime::Format::DateParse->parse_datetime($maintenance_end
+    );
+    #    return $c->render(text => "Maintenance until ".$localtime_end->strftime('%Y-%m-%d %H:%M [%Z]'));
+    return $c->render(
+        maintenance_end => $maintenance_end
+        ,template => '/main/maintenance'
+    );
+}
+
 my $routes = app->routes->children;
 for my $route (@$routes){
     $route->pattern->quote_start('(');

templates/bootstrap/navigation.html.ep

@@ -32,6 +32,9 @@ navbar-dark bg-dark fixed-top navbar-expand-lg navbar-inverse">
                             <a class="dropdown-item" href="/admin/messages"><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;<%=l 'messages' %></a>
 % if ($monitoring) {
                             <a class="dropdown-item" href="/admin/monitoring"><i class="fas fa-tachometer-alt" aria-hidden="true"></i>&nbsp<%=l 'monitoring' %></a>
+% }
+% if ($_user->is_admin) {
+                            <a class="dropdown-item" href="/admin/settings"><i class="fas fa-tachometer-alt" aria-hidden="true"></i>&nbsp<%=l 'settings' %></a>
 % }
                       </div>
                     </li>

templates/main/admin_settings.html.ep

+<!DOCTYPE html>
+<html ng-app="ravada.app">
+%= include 'bootstrap/header'
+<body id="page-top" data-spy="scroll" data-target="fixed-top" role="document">
+<div id="wrapper">
+    %= include 'bootstrap/navigation'
+<div id="page-wrapper"
+                ng-controller="settings_global"
+                ng-init="init('<%= url_for('ws_subscribe')->to_abs %>')"
+>
+    <div class="page-header">
+        <div class="card">
+            <div class="card-header">
+                <h2>Global Settings</h2>
+            </div>
+        </div>
+    </div>
+    <div>
+        <form name="formSettings">
+        <div class="row" ng-hide="true">
+            <div class="col-md-2">
+            <label for="falback">Fallback</label>
+            </div>
+            <div class="col-md-2">
+            <input name="fallback" ng-model="settings.frontend.fallback.value" type="checkbox"
+                ng-true-value="1" ng-false-value="0"
+            >
+            </div>
+        </div>
+        <div class="row" ng-hide="true">
+            <div class="col-md-2">
+            <label for="session timeout">Session timeout</label>
+            </div>
+            <div class="col-md-2">
+            <input name="fallback" ng-model="settings.frontend.session_timeout.value"
+                type="text">
+            </div>
+        </div>
+        <div class="row">
+            <div class="col-md-2">
+            <label for="maintenance">Maintenance</label>
+            </div>
+            <div class="col-md-2">
+            <input name="maintenance" ng-model="settings.frontend.maintenance.value"
+                ng-true-value="1" ng-false-value="0"
+                type="checkbox">
+            </div>
+            <div>
+                <%= l 'Admin users can still log in from' %>
+                <a href="<%= $url_login %>"><%= $url_login %></a>
+            </div>
+        </div>
+        <div class="row" ng-show="settings.frontend.maintenance.value == 1">
+            <div class="col-md-2">
+            <label for="maintenance_start">Maintenance Start</label>
+            </div>
+            <div class="col-md-4">
+            <input name="maintenance_start" ng-model="settings.frontend.maintenance_start.value"
+                type="datetime-local">
+            </div>
+        </div>
+
+        <div class="row" ng-show="settings.frontend.maintenance.value == 1">
+            <div class="col-md-2">
+            <label for="maintenance_end">Maintenance End</label>
+            </div>
+            <div class="col-md-4">
+            <input name="maintenance_end" ng-model="settings.frontend.maintenance_end.value"
+                type="datetime-local">
+            </div>
+        </div>
+
+        <div class="row">
+            <div class="col-md-2">
+                <button ng-click="update_settings()"
+                    ng-disabled="!formSettings.$valid || formSettings.$pristine">
+                    save
+                </button>
+                <button ng-click="load_settings()"
+                    ng-disabled="formSettings.$pristine">cancel</button>
+            </div>
+        </div>
+
+
+        </form>
+    </div>
+</div>
+</div>
+
+    %= include 'bootstrap/scripts'
+    %= include 'bootstrap/messages'
+
+</body>
+</html>

templates/main/maintenance.html.ep

+<!DOCTYPE html>
+<html ng-app="ravada.app">
+
+<body>
+
+<div id="wrapper">
+
+    <div ng-controller="maintenance"
+        ng-init="init('<%= $maintenance_end %>')"
+    >
+        <div ng-cloak="1">
+        <%= l 'Sorry'%>.
+        <%= l 'Server in maintenance until' %> {{maintenance_end | date:'medium'}}
+        </div>
+    </div>
+%= include 'bootstrap/scripts'
+
+</div><!-- wrapper -->
+
+
+</body>
+</html>