From 81e028b791d626588f949360adf2d2f12b8ffbb9 Mon Sep 17 00:00:00 2001
From: Fabien Meghazi <fme@openerp.com>
Date: Wed, 14 Aug 2013 18:43:22 +0200
Subject: [PATCH] [ADD] QWeb: add async api (backward compatible)

bzr revid: fme@openerp.com-20130814164322-cny24d0i6tg4ftvn
---
 addons/web/static/lib/qweb/qweb2.js | 94 ++++++++++++++++++++---------
 1 file changed, 65 insertions(+), 29 deletions(-)

diff --git a/addons/web/static/lib/qweb/qweb2.js b/addons/web/static/lib/qweb/qweb2.js
index 52e975322e5..4512b749682 100644
--- a/addons/web/static/lib/qweb/qweb2.js
+++ b/addons/web/static/lib/qweb/qweb2.js
@@ -226,10 +226,27 @@ QWeb2.Engine = (function() {
     }
 
     QWeb2.tools.extend(Engine.prototype, {
-        add_template : function(template) {
+        /**
+         * Add a template to the engine
+         *
+         * @param {String|Document} template Template as string or url or DOM Document
+         * @param {Function} [callback] Called when the template is loaded, force async request
+         */
+        add_template : function(template, callback) {
+            var self = this;
             this.templates_resources.push(template);
             if (template.constructor === String) {
-                template = this.load_xml(template);
+                return this.load_xml(template, function (err, xDoc) {
+                    if (err) {
+                        if (callback) {
+                            return callback(err);
+                        } else {
+                            throw err;
+                        }
+                    }
+                    self.add_template(xDoc, callback);
+                });
+                template = this.load_xml(template, callback);
             }
             var ec = (template.documentElement && template.documentElement.childNodes) || template.childNodes || [];
             for (var i = 0; i < ec.length; i++) {
@@ -262,35 +279,56 @@ QWeb2.Engine = (function() {
                     }
                 }
             }
+            if (callback) {
+                callback(null, template);
+            }
             return true;
         },
-        load_xml : function(s) {
+        load_xml : function(s, callback) {
+            var self = this;
+            var async = !!callback;
             s = this.tools.trim(s);
             if (s.charAt(0) === '<') {
-                return this.load_xml_string(s);
+                var tpl = this.load_xml_string(s);
+                if (callback) {
+                    callback(null, tpl);
+                }
+                return tpl;
             } else {
                 var req = this.get_xhr();
-                if (req) {
-                    // TODO: third parameter is async : https://developer.mozilla.org/en/XMLHttpRequest#open()
-                    // do an on_ready in QWeb2{} that could be passed to add_template
-                    if (this.debug) {
-                        s += '?debug=' + (new Date()).getTime(); // TODO fme: do it properly in case there's already url parameters
-                    }
-                    req.open('GET', s, false);
-                    req.send(null);
-                    var xDoc = req.responseXML;
-                    if (xDoc) {
-                        if (!xDoc.documentElement) {
-                            throw new Error("QWeb2: This xml document has no root document : " + xDoc.responseText);
-                        }
-                        if (xDoc.documentElement.nodeName == "parsererror") {
-                            return this.tools.exception(xDoc.documentElement.childNodes[0].nodeValue);
-                        }
-                        return xDoc;
-                    } else {
-                        return this.load_xml_string(req.responseText);
-                    }
+                if (this.debug) {
+                    s += '?debug=' + (new Date()).getTime(); // TODO fme: do it properly in case there's already url parameters
                 }
+                req.open('GET', s, async);
+                if (async) {
+                    req.onreadystatechange = function() {
+                        if (req.readyState == 4) {
+                            if (req.status == 200) {
+                                callback(null, self._parse_from_request(req));
+                            } else {
+                                callback(new Error("Can't load template, http status " + req.status));
+                            }
+                        }
+                    };
+                }
+                req.send(null);
+                if (!async) {
+                    return this._parse_from_request(req);
+                }
+            }
+        },
+        _parse_from_request: function(req) {
+            var xDoc = req.responseXML;
+            if (xDoc) {
+                if (!xDoc.documentElement) {
+                    throw new Error("QWeb2: This xml document has no root document : " + xDoc.responseText);
+                }
+                if (xDoc.documentElement.nodeName == "parsererror") {
+                    throw new Error("QWeb2: Could not parse document :" + xDoc.documentElement.childNodes[0].nodeValue);
+                }
+                return xDoc;
+            } else {
+                return this.load_xml_string(req.responseText);
             }
         },
         load_xml_string : function(s) {
@@ -298,17 +336,15 @@ QWeb2.Engine = (function() {
                 var dp = new DOMParser();
                 var r = dp.parseFromString(s, "text/xml");
                 if (r.body && r.body.firstChild && r.body.firstChild.nodeName == 'parsererror') {
-                    return this.tools.exception(r.body.innerText);
+                    throw new Error("QWeb2: Could not parse document :" + r.body.innerText);
                 }
                 return r;
             }
             var xDoc;
             try {
-                // new ActiveXObject("Msxml2.DOMDocument.4.0");
                 xDoc = new ActiveXObject("MSXML2.DOMDocument");
             } catch (e) {
-                return this.tools.exception(
-                    "Could not find a DOM Parser: " + e.message);
+                throw new Error("Could not find a DOM Parser: " + e.message);
             }
             xDoc.async = false;
             xDoc.preserveWhiteSpace = true;
@@ -325,7 +361,7 @@ QWeb2.Engine = (function() {
             try {
                 return new ActiveXObject('MSXML2.XMLHTTP.3.0');
             } catch (e) {
-                return null;
+                throw new Error("Could not get XHR");
             }
         },
         compile : function(node) {