Send browser errors back to the server

(imported from commit 8c676017e8b3fc4f17552db15d32266099dba8f2)

humbug/urls.py

@@ -74,6 +74,7 @@ urlpatterns = patterns('',
     url(r'^json/tutorial_send_message$',    'zephyr.views.json_tutorial_send_message'),
     url(r'^json/change_enter_sends$',       'zephyr.views.json_change_enter_sends'),
     url(r'^json/get_profile$',              'zephyr.views.json_get_profile'),
+    url(r'^json/report_error$',             'zephyr.views.json_report_error'),
 
     # These are json format views used by the API.  They require an API key.
     url(r'^api/v1/get_messages$',           'zephyr.tornadoviews.api_get_messages'),

zephyr/static/js/blueslip.js

@@ -5,6 +5,25 @@ var blueslip = (function () {
 
 var exports = {};
 
+var error_has_stack = Error().hasOwnProperty('stack');
+
+function report_error(msg) {
+    var stack;
+    if (error_has_stack) {
+        stack = Error().stack;
+    } else {
+        stack = 'No stacktrace available';
+    }
+
+    $.ajax({
+        type:     'POST',
+        url:      '/json/report_error',
+        dataType: 'json',
+        data:     { message: msg, stacktrace: stack },
+        timeout:  10*1000
+    });
+}
+
 exports.log = function blueslip_log (msg) {
     console.log(msg);
 };
@@ -25,10 +44,15 @@ exports.error = function blueslip_error (msg) {
         throw new Error(msg);
     } else {
         console.error(msg);
+        report_error(msg);
     }
 };
 
 exports.fatal = function blueslip_fatal (msg) {
+    if (! debug_mode) {
+        report_error(msg);
+    }
+
     throw new Error(msg);
 };
 

zephyr/views.py

@@ -11,7 +11,7 @@ from django.core import validators
 from django.contrib.auth.views import login as django_login_page, \
     logout_then_login as django_logout_then_login
 from django.db.models import Q
-from django.core.mail import send_mail
+from django.core.mail import send_mail, mail_admins
 from zephyr.models import Message, UserProfile, Stream, Subscription, \
     Recipient, get_huddle, Realm, UserMessage, \
     PreregistrationUser, get_client, MitUser, User, UserActivity, \
@@ -1403,3 +1403,10 @@ def json_update_active_status(request, user_profile,
 @authenticated_json_post_view
 def json_get_active_statuses(request, user_profile):
     return get_status_list(user_profile)
+
+@authenticated_json_post_view
+@has_request_variables
+def json_report_error(request, user_profile, message=POST, stacktrace=POST):
+    mail_admins("Browser error for %s" % (user_profile.user.email,),
+                "Message:\n%s\n\nStacktrace:\n%s" % (message, stacktrace))
+    return json_success()