Reconnect when the websocket connection closes unexpectedly

IPython/frontend/html/notebook/static/js/kernel.js

@@ -1,387 +1,386 b''
 //----------------------------------------------------------------------------
 //  Copyright (C) 2008-2011  The IPython Development Team
 //
 //  Distributed under the terms of the BSD License.  The full license is in
 //  the file COPYING, distributed as part of this software.
 //----------------------------------------------------------------------------
 
 //============================================================================
 // Kernel
 //============================================================================
 
 var IPython = (function (IPython) {
 
     var utils = IPython.utils;
 
     // Initialization and connection.
 
     var Kernel = function (base_url) {
         this.kernel_id = null;
         this.shell_channel = null;
         this.iopub_channel = null;
         this.base_url = base_url;
         this.running = false;
         this.username = "username";
         this.session_id = utils.uuid();
         this._msg_callbacks = {};
 
         if (typeof(WebSocket) !== 'undefined') {
             this.WebSocket = WebSocket;
         } else if (typeof(MozWebSocket) !== 'undefined') {
             this.WebSocket = MozWebSocket;
         } else {
             alert('Your browser does not have WebSocket support, please try Chrome, Safari or Firefox ≥ 6. Firefox 4 and 5 are also supported by you have to enable WebSockets in about:config.');
         };
     };
 
 
     Kernel.prototype._get_msg = function (msg_type, content) {
         var msg = {
             header : {
                 msg_id : utils.uuid(),
                 username : this.username,
                 session : this.session_id,
                 msg_type : msg_type
             },
             content : content,
             parent_header : {}
         };
         return msg;
     };
 
     Kernel.prototype.start = function (notebook_id) {
         var that = this;
         if (!this.running) {
             var qs = $.param({notebook:notebook_id});
             var url = this.base_url + '?' + qs;
             $.post(url,
                 $.proxy(that._kernel_started,that),
                 'json'
             );
         };
     };
 
 
     Kernel.prototype.restart = function () {
         $([IPython.events]).trigger('status_restarting.Kernel');
         var that = this;
         if (this.running) {
             this.stop_channels();
             var url = this.kernel_url + "/restart";
             $.post(url,
                 $.proxy(that._kernel_started, that),
                 'json'
             );
         };
     };
 
 
     Kernel.prototype._kernel_started = function (json) {
         console.log("Kernel started: ", json.kernel_id);
         this.running = true;
         this.kernel_id = json.kernel_id;
         this.ws_url = json.ws_url;
         this.kernel_url = this.base_url + "/" + this.kernel_id;
         this.start_channels();
         this.shell_channel.onmessage = $.proxy(this._handle_shell_reply,this);
         this.iopub_channel.onmessage = $.proxy(this._handle_iopub_reply,this);
     };
 
 
     Kernel.prototype._websocket_closed = function(ws_url, early){
         var msg;
         var parent_item = $('body');
         if (early) {
             msg = "Websocket connection to " + ws_url + " could not be established." +
             " You will NOT be able to run code." +
             " Your browser may not be compatible with the websocket version in the server," +
             " or if the url does not look right, there could be an error in the" +
             " server's configuration.";
         } else {
-            msg = "Websocket connection closed unexpectedly." +
-            " The kernel will no longer be responsive.";
-        }
+ 	    this.start_channels();
+ 	}
         var dialog = $('<div/>');
         dialog.html(msg);
         parent_item.append(dialog);
         dialog.dialog({
             resizable: false,
             modal: true,
             title: "Websocket closed",
             closeText: "",
             close: function(event, ui) {$(this).dialog('destroy').remove();},
             buttons : {
                 "OK": function () {
                     $(this).dialog('close');
                 }
             }
         });
 
     };
 
     Kernel.prototype.start_channels = function () {
         var that = this;
         this.stop_channels();
         var ws_url = this.ws_url + this.kernel_url;
         console.log("Starting WS:", ws_url);
         this.shell_channel = new this.WebSocket(ws_url + "/shell");
         this.iopub_channel = new this.WebSocket(ws_url + "/iopub");
         send_cookie = function(){
             this.send(document.cookie);
         };
         var already_called_onclose = false; // only alert once
         ws_closed_early = function(evt){
             if (already_called_onclose){
                 return;
             }
             already_called_onclose = true;
             if ( ! evt.wasClean ){
                 that._websocket_closed(ws_url, true);
             }
         };
         ws_closed_late = function(evt){
             if (already_called_onclose){
                 return;
             }
             already_called_onclose = true;
             if ( ! evt.wasClean ){
                 that._websocket_closed(ws_url, false);
             }
         };
         this.shell_channel.onopen = send_cookie;
         this.shell_channel.onclose = ws_closed_early;
         this.iopub_channel.onopen = send_cookie;
         this.iopub_channel.onclose = ws_closed_early;
         // switch from early-close to late-close message after 1s
         setTimeout(function(){
             that.shell_channel.onclose = ws_closed_late;
             that.iopub_channel.onclose = ws_closed_late;
         }, 1000);
     };
 
 
     Kernel.prototype.stop_channels = function () {
         if (this.shell_channel !== null) {
             this.shell_channel.onclose = function (evt) {};
             this.shell_channel.close();
             this.shell_channel = null;
         };
         if (this.iopub_channel !== null) {
             this.iopub_channel.onclose = function (evt) {};
             this.iopub_channel.close();
             this.iopub_channel = null;
         };
     };
 
     // Main public methods.
 
     Kernel.prototype.object_info_request = function (objname, callbacks) {
         // When calling this method pass a callbacks structure of the form:
         //
         // callbacks = {
         //  'object_info_reply': object_into_reply_callback
         // }
         //
         // The object_info_reply_callback will be passed the content object of the
         // object_into_reply message documented here:
         //
         // http://ipython.org/ipython-doc/dev/development/messaging.html#object-information
         if(typeof(objname)!=null && objname!=null)
         {
             var content = {
                 oname : objname.toString(),
             };
             var msg = this._get_msg("object_info_request", content);
             this.shell_channel.send(JSON.stringify(msg));
             this.set_callbacks_for_msg(msg.header.msg_id, callbacks);
             return msg.header.msg_id;
         }
         return;
     }
 
     Kernel.prototype.execute = function (code, callbacks, options) {
         // The options object should contain the options for the execute call. Its default
         // values are:
         //
         // options = {
         //   silent : true,
         //   user_variables : [],
         //   user_expressions : {},
         //   allow_stdin : false
         // }
         //
         // When calling this method pass a callbacks structure of the form:
         //
         // callbacks = {
         //  'execute_reply': execute_reply_callback,
         //  'output': output_callback,
         //  'clear_output': clear_output_callback,
         //  'set_next_input': set_next_input_callback
         // }
         //
         // The execute_reply_callback will be passed the content object of the execute_reply
         // message documented here:
         //
         // http://ipython.org/ipython-doc/dev/development/messaging.html#execute
         //
         // The output_callback will be passed msg_type ('stream','display_data','pyout','pyerr')
         // of the output and the content object of the PUB/SUB channel that contains the
         // output:
         //
         // http://ipython.org/ipython-doc/dev/development/messaging.html#messages-on-the-pub-sub-socket
         //
         // The clear_output_callback will be passed a content object that contains
         // stdout, stderr and other fields that are booleans.
         //
         // The set_next_input_callback will bepassed the text that should become the next
         // input cell.
 
         var content = {
             code : code,
             silent : true,
             user_variables : [],
             user_expressions : {},
             allow_stdin : false
         };
 		$.extend(true, content, options)
         var msg = this._get_msg("execute_request", content);
         this.shell_channel.send(JSON.stringify(msg));
         this.set_callbacks_for_msg(msg.header.msg_id, callbacks);
         return msg.header.msg_id;
     };
 
 
     Kernel.prototype.complete = function (line, cursor_pos, callbacks) {
         // When calling this method pass a callbacks structure of the form:
         //
         // callbacks = {
         //  'complete_reply': complete_reply_callback
         // }
         //
         // The complete_reply_callback will be passed the content object of the
         // complete_reply message documented here:
         //
         // http://ipython.org/ipython-doc/dev/development/messaging.html#complete
         callbacks = callbacks || {};
         var content = {
             text : '',
             line : line,
             cursor_pos : cursor_pos
         };
         var msg = this._get_msg("complete_request", content);
         this.shell_channel.send(JSON.stringify(msg));
         this.set_callbacks_for_msg(msg.header.msg_id, callbacks);
         return msg.header.msg_id;
     };
 
 
     Kernel.prototype.interrupt = function () {
         if (this.running) {
             $([IPython.events]).trigger('status_interrupting.Kernel');
             $.post(this.kernel_url + "/interrupt");
         };
     };
 
 
     Kernel.prototype.kill = function () {
         if (this.running) {
             this.running = false;
             var settings = {
                 cache : false,
                 type : "DELETE"
             };
             $.ajax(this.kernel_url, settings);
         };
     };
 
 
     // Reply handlers.
 
     Kernel.prototype.get_callbacks_for_msg = function (msg_id) {
         var callbacks = this._msg_callbacks[msg_id];
         return callbacks;
     };
 
 
     Kernel.prototype.set_callbacks_for_msg = function (msg_id, callbacks) {
         this._msg_callbacks[msg_id] = callbacks || {};
     }
 
 
     Kernel.prototype._handle_shell_reply = function (e) {
         reply = $.parseJSON(e.data);
         var header = reply.header;
         var content = reply.content;
         var msg_type = header.msg_type;
         var callbacks = this.get_callbacks_for_msg(reply.parent_header.msg_id);
         if (callbacks !== undefined) {
             var cb = callbacks[msg_type];
             if (cb !== undefined) {
                 cb(content);
             }
         };
 
         if (content.payload !== undefined) {
             var payload = content.payload || [];
             this._handle_payload(callbacks, payload);
         }
     };
 
 
     Kernel.prototype._handle_payload = function (callbacks, payload) {
         var l = payload.length;
         // Payloads are handled by triggering events because we don't want the Kernel
         // to depend on the Notebook or Pager classes.
         for (var i=0; i<l; i++) {
             if (payload[i].source === 'IPython.zmq.page.page') {
                 var data = {'text':payload[i].text}
                 $([IPython.events]).trigger('open_with_text.Pager', data);
             } else if (payload[i].source === 'IPython.zmq.zmqshell.ZMQInteractiveShell.set_next_input') {
                 if (callbacks.set_next_input !== undefined) {
                     callbacks.set_next_input(payload[i].text)
                 }
             }
         };
     };
 
 
     Kernel.prototype._handle_iopub_reply = function (e) {
         reply = $.parseJSON(e.data);
         var content = reply.content;
         var msg_type = reply.header.msg_type;
         var callbacks = this.get_callbacks_for_msg(reply.parent_header.msg_id);
         if (msg_type !== 'status' && callbacks === undefined) {
             // Message not from one of this notebook's cells and there are no
             // callbacks to handle it.
             return;
         }
         var output_types = ['stream','display_data','pyout','pyerr'];
         if (output_types.indexOf(msg_type) >= 0) {
             var cb = callbacks['output'];
             if (cb !== undefined) {
                 cb(msg_type, content);
             }
         } else if (msg_type === 'status') {
             if (content.execution_state === 'busy') {
                 $([IPython.events]).trigger('status_busy.Kernel');
             } else if (content.execution_state === 'idle') {
                 $([IPython.events]).trigger('status_idle.Kernel');
             } else if (content.execution_state === 'dead') {
                 this.stop_channels();
                 $([IPython.events]).trigger('status_dead.Kernel');
             };
         } else if (msg_type === 'clear_output') {
             var cb = callbacks['clear_output'];
             if (cb !== undefined) {
                 cb(content);
             }
         };
     };
 
 
     IPython.Kernel = Kernel;
 
     return IPython;
 
 }(IPython));