implement reconnect logic

this improves the closed gracefully/error logic
(detects an error if we disconnect immediately after connecting)
and implements a reconnect for vms/containers

if we have a disconnect, we check /cluster/resources
(and /nodes/<node>/lxc/<id>/status/current) if we are migrated
and reconnect the console window or reload the window

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>

diff --git a/src/www/main.js b/src/www/main.js
index 461b6e6f9a4c9179c265a306e589988e823734fa..6fec72f04dbf49d98012700574615cd92e3a28bf 100644 (file)
--- a/src/www/main.js
+++ b/src/www/main.js
@@ -6,6 +6,7 @@ var states = {
     connected:     3,
     disconnecting: 4,
     disconnected:  5,
+    reconnecting:  6,
 };
 
 var term,
@@ -15,7 +16,13 @@ var term,
     ticket,
     resize,
     ping,
-    state = states.start;
+    state = states.start,
+    starttime = new Date();
+
+var type = getQueryParameter('console');
+var vmid = getQueryParameter('vmid');
+var vmname = getQueryParameter('vmname');
+var nodename = getQueryParameter('node');
 
 function updateState(newState, msg) {
     var timeout, severity, message;
@@ -33,18 +40,30 @@ function updateState(newState, msg) {
            timeout = 0;
            severity = severities.warning;
            break;
+       case states.reconnecting:
+           message = "Reconnecting...";
+           timeout = 0;
+           severity = severities.warning;
+           break;
        case states.disconnected:
            switch (state) {
                case states.start:
                case states.connecting:
+               case states.reconnecting:
                    message = "Connection failed";
                    timeout = 0;
                    severity = severities.error;
                    break;
                case states.connected:
                case states.disconnecting:
-                   message = "Connection closed";
-                   timeout = 0;
+                   var time_since_started = new Date() - starttime;
+                   timeout = 5000;
+                   if (time_since_started > 5*1000) {
+                       message = "Connection closed";
+                   } else {
+                       message = "Connection failed";
+                       severity = severities.error;
+                   }
                    break;
                case states.disconnected:
                    // no state change
@@ -81,10 +100,6 @@ function createTerminal() {
     protocol = (location.protocol === 'https:') ? 'wss://' : 'ws://';
 
     var params = {};
-    var type = getQueryParameter('console');
-    var vmid = getQueryParameter('vmid');
-    var vmname = getQueryParameter('vmname');
-    var nodename = getQueryParameter('node');
     var url = '/nodes/' + nodename;
     switch (type) {
        case 'kvm':
@@ -110,8 +125,8 @@ function createTerminal() {
            socket = new WebSocket(socketURL, 'binary');
            socket.binaryType = 'arraybuffer';
            socket.onopen = runTerminal;
-           socket.onclose = stopTerminal;
-           socket.onerror = errorTerminal;
+           socket.onclose = tryReconnect;
+           socket.onerror = tryReconnect;
            window.onbeforeunload = stopTerminal;
            updateState(states.connecting);
        },
@@ -160,6 +175,111 @@ function runTerminal() {
     setTimeout(function() {term.fit();}, 250);
 }
 
+function getLxcStatus(callback) {
+    API2Request({
+       method: 'GET',
+       url: '/nodes/' + nodename + '/lxc/' + vmid + '/status/current',
+       success: function(result) {
+           if (typeof callback === 'function') {
+               callback(true, result);
+           }
+       },
+       failure: function(msg) {
+           if (typeof callback === 'function') {
+               callback(false, msg);
+           }
+       }
+    });
+}
+
+function checkMigration() {
+    var apitype = type;
+    if (apitype === 'kvm') {
+       apitype = 'qemu';
+    }
+    API2Request({
+       method: 'GET',
+       params: {
+           type: 'vm'
+       },
+       url: '/cluster/resources',
+       success: function(result) {
+           // if not yet migrated , wait and try again
+           // if not migrating and stopped, cancel
+           // if started, connect
+           result.data.forEach(function(entity) {
+               if (entity.id === (apitype + '/' + vmid)) {
+                   var started = entity.status === 'running';
+                   var migrated = entity.node !== nodename;
+                   if (migrated) {
+                       if (started) {
+                           // goto different node
+                           location.href = '?console=' + type +
+                               '&xtermjs=1&vmid=' + vmid + '&vmname=' +
+                               vmname + '&node=' + entity.node;
+                       } else {
+                           // wait again
+                           updateState(states.reconnecting, 'waiting for migration to finish...');
+                           setTimeout(checkMigration, 5000);
+                       }
+                   } else {
+                       if (type === 'lxc') {
+                           // we have to check the status of the
+                           // container to know if it has the
+                           // migration lock
+                           getLxcStatus(function(success, result) {
+                               if (success) {
+                                   if (result.data.lock === 'migrate') {
+                                       // still waiting
+                                       updateState(states.reconnecting, 'waiting for migration to finish...');
+                                       setTimeout(checkMigration, 5000);
+                                   } else {
+                                       stopTerminal();
+                                   }
+                               } else {
+                                   // probably the status call failed because
+                                   // the ct is already somewhere else, so retry
+                                   setTimeout(checkMigration, 1000);
+                               }
+                           });
+                       } else if (started) {
+                           // this happens if we have old data in
+                           // /cluster/resources, or the connection
+                           // disconnected, so simply try to reload here
+                           location.reload();
+                       } else if (type === 'kvm') {
+                           // it seems the guest simply stopped
+                           stopTerminal();
+                       }
+                   }
+
+                   return;
+               }
+           });
+       },
+       failure: function(msg) {
+           errorTerminal({msg: msg});
+       }
+    });
+}
+
+function tryReconnect() {
+    var time_since_started = new Date() - starttime;
+    var type = getQueryParameter('console');
+    if (time_since_started < 5*1000) { // 5 seconds
+       stopTerminal({});
+       return;
+    } else if (type === 'shell') {
+       updateState(states.reconnecting, 'trying to reconnect...');
+       setTimeout(function() {
+           location.reload();
+       }, 1000);
+    }
+
+    updateState(states.disconnecting, 'Detecting migration...');
+    setTimeout(checkMigration, 5000);
+}
+
 function stopTerminal(event) {
     term.off('resize');
     term.off('data');