diff --git a/addons/web/static/src/js/chrome.js b/addons/web/static/src/js/chrome.js
index 7e4b9a46fe8..9c73ca33165 100644
--- a/addons/web/static/src/js/chrome.js
+++ b/addons/web/static/src/js/chrome.js
@@ -903,7 +903,7 @@ instance.web.UserMenu =  instance.web.Widget.extend({
                 if(res.company_id[0] > 1)
                     topbar_name = _.str.sprintf("%s (%s)", topbar_name, res.company_id[1]);
                 self.$el.find('.oe_topbar_name').text(topbar_name);
-                var avatar_src = _.str.sprintf('%s/web/binary/image?session_id=%s&model=res.users&field=image_small&id=%s', self.session.prefix, self.session.session_id, self.session.uid);
+                var avatar_src = self.session.url('/web/binary/image', {model:'res.users', field: 'image_small', id: self.session.uid});
                 $avatar.attr('src', avatar_src);
             });
         };
diff --git a/addons/web/static/src/js/corelib.js b/addons/web/static/src/js/corelib.js
index 879cf94dcdd..6ea0fd53372 100644
--- a/addons/web/static/src/js/corelib.js
+++ b/addons/web/static/src/js/corelib.js
@@ -1320,7 +1320,7 @@ instance.web.JsonRPC = instance.web.Class.extend(instance.web.PropertiesMixin, {
             }
         };
 
-        url.url = this.get_url(url.url);
+        url.url = this.url(url.url, null);
         var ajax = _.extend({
             type: "GET",
             dataType: 'jsonp', 
@@ -1376,8 +1376,17 @@ instance.web.JsonRPC = instance.web.Class.extend(instance.web.PropertiesMixin, {
             return deferred.done(set_sid);
         }
     },
-    get_url: function (file) {
-        return this.prefix + file;
+
+    url: function(path, params) {
+        var qs = '';
+        if (!_.isNull(params)) {
+            params = _.extend(params || {}, {session_id: this.session_id});
+            if (this.httpsessionid) {
+                params.sid = this.httpsessionid;
+            }
+            qs = '?' + $.param(params);
+        }
+        return this.prefix + path + qs;
     },
 });
 
diff --git a/addons/web/static/src/js/coresetup.js b/addons/web/static/src/js/coresetup.js
index 87f659340f6..f3166285fe7 100644
--- a/addons/web/static/src/js/coresetup.js
+++ b/addons/web/static/src/js/coresetup.js
@@ -201,7 +201,7 @@ instance.web.Session = instance.web.JsonRPC.extend( /** @lends instance.web.Sess
         var self = this;
         _.each(files, function (file) {
             $('head').append($('<link>', {
-                'href': self.get_url(file),
+                'href': self.url(file, null),
                 'rel': 'stylesheet',
                 'type': 'text/css'
             }));
@@ -210,11 +210,11 @@ instance.web.Session = instance.web.JsonRPC.extend( /** @lends instance.web.Sess
     load_js: function(files) {
         var self = this;
         var d = $.Deferred();
-        if(files.length != 0) {
+        if(files.length !== 0) {
             var file = files.shift();
             var tag = document.createElement('script');
             tag.type = 'text/javascript';
-            tag.src = self.get_url(file);
+            tag.src = self.url(file, null);
             tag.onload = tag.onreadystatechange = function() {
                 if ( (tag.readyState && tag.readyState != "loaded" && tag.readyState != "complete") || tag.onload_done )
                     return;
diff --git a/addons/web/static/src/js/view_form.js b/addons/web/static/src/js/view_form.js
index 8f5bb86e6b9..867569e2ea5 100644
--- a/addons/web/static/src/js/view_form.js
+++ b/addons/web/static/src/js/view_form.js
@@ -4956,8 +4956,12 @@ instance.web.form.FieldBinaryImage = instance.web.form.FieldBinary.extend({
             var field = this.name;
             if (this.options.preview_image)
                 field = this.options.preview_image;
-            url = '/web/binary/image?session_id=' + this.session.session_id + '&model=' +
-                this.view.dataset.model +'&id=' + id + '&field=' + field + '&t=' + (new Date().getTime());
+            url = this.session.url('/web/binary/image', {
+                                        model: this.view.dataset.model,
+                                        id: id,
+                                        field: field,
+                                        t: (new Date().getTime()),
+            });
         } else {
             url = this.placeholder;
         }
@@ -5017,7 +5021,7 @@ instance.web.form.FieldOne2ManyBinaryMultiFiles = instance.web.form.AbstractFiel
         return _.map(this.get('value'), function (value) { return commands.link_to( value.id ); });
     },
     get_file_url: function (attachment) {
-        return instance.origin + '/web/binary/saveas?session_id=' + this.session.session_id + '&model=ir.attachment&field=datas&filename_field=datas_fname&id=' + attachment['id'];
+        return this.session.url('/web/binary/saveas', {model: 'ir.attachment', field: 'datas', filename_field: 'datas_fname', id: attachment['id']});
     },
     render_value: function () {
         var render = $(instance.web.qweb.render('FieldBinaryFileUploader.files', {'widget': this}));
diff --git a/addons/web/static/src/js/view_list.js b/addons/web/static/src/js/view_list.js
index 700c126d68d..db8c962efc7 100644
--- a/addons/web/static/src/js/view_list.js
+++ b/addons/web/static/src/js/view_list.js
@@ -2173,9 +2173,7 @@ instance.web.list.Binary = instance.web.list.Column.extend({
         if (value && value.substr(0, 10).indexOf(' ') == -1) {
             download_url = "data:application/octet-stream;base64," + value;
         } else {
-            download_url = _.str.sprintf(
-                '/web/binary/saveas?session_id=%s&model=%s&field=%s&id=%d',
-                instance.session.session_id, options.model, this.id, options.id);
+            download_url = this.session.url('/web/binary/saveas', {model: options.model, field: this.id, id: options.id});
             if (this.filename) {
                 download_url += '&filename_field=' + this.filename;
             }
diff --git a/addons/web/static/src/js/views.js b/addons/web/static/src/js/views.js
index 19336ec3655..d29ac70bb5a 100644
--- a/addons/web/static/src/js/views.js
+++ b/addons/web/static/src/js/views.js
@@ -1102,11 +1102,11 @@ instance.web.Sidebar = instance.web.Widget.extend({
     on_attachments_loaded: function(attachments) {
         var self = this;
         var items = [];
-        var prefix = this.session.origin + '/web/binary/saveas?session_id=' + self.session.session_id + '&model=ir.attachment&field=datas&filename_field=name&id=';
+        var prefix = this.session.url('/web/binary/saveas', {model: 'ir.attachment', field: 'datas', filename_field: 'name'});
         _.each(attachments,function(a) {
             a.label = a.name;
             if(a.type === "binary") {
-                a.url = prefix  + a.id + '&t=' + (new Date().getTime());
+                a.url = prefix  + '&id=' + a.id + '&t=' + (new Date().getTime());
             }
         });
         self.items['files'] = attachments;
diff --git a/addons/web_kanban/static/src/js/kanban.js b/addons/web_kanban/static/src/js/kanban.js
index 25379e946b6..8526dbdc8de 100644
--- a/addons/web_kanban/static/src/js/kanban.js
+++ b/addons/web_kanban/static/src/js/kanban.js
@@ -995,7 +995,7 @@ instance.web_kanban.KanbanRecord = instance.web.Widget.extend({
             id = escape(JSON.stringify(id));
             if (options.preview_image)
                 field = options.preview_image;
-            url = instance.session.prefix + '/web/binary/image?session_id=' + this.session.session_id + '&model=' + model + '&field=' + field + '&id=' + id;
+            url = this.session.url('/web/binary/image', {model: model, field: field, id: id});
             if (cache !== undefined) {
                 // Set the cache duration in seconds.
                 url += '&cache=' + parseInt(cache, 10);