Try to handle errors when connecting to amavis.

fixes #257

modoboa/lib/dbutils.py

@@ -1,7 +1,10 @@
 # coding: utf-8
 from django.db import connection
 from django.conf import settings
-            
+from django.utils.translation import ugettext as _
+from modoboa.lib.exceptions import InternalError
+
+
 def db_table_exists(table, cursor=None):
     """Check if table exists
 
@@ -20,14 +23,18 @@ def db_table_exists(table, cursor=None):
     else:
         return table in table_names
 
-def db_type(connection="default"):
+
+def db_type(cname="default"):
     """Return the type of the *default* database
 
     Supported values : 'postgres', 'mysql', 'sqlite'
 
+    :param str cname: connection name
     :return: a string or None
     """
+    if not cname in settings.DATABASES:
+        raise InternalError(_("Connection to database %s not configured" % cname))
     for t in ['postgres', 'mysql', 'sqlite']:
-        if settings.DATABASES[connection]['ENGINE'].find(t) != -1:
+        if settings.DATABASES[cname]['ENGINE'].find(t) != -1:
             return t
     return None

modoboa/lib/webutils.py

@@ -8,7 +8,7 @@ import re
 import json
 from django.http import HttpResponse, HttpResponseRedirect
 from django.contrib.auth.decorators import login_required
-from django.shortcuts import render_to_response
+from django.shortcuts import render, render_to_response
 from django.template.loader import render_to_string
 from django import template
 from django.conf import settings
@@ -27,9 +27,8 @@ def _render_to_string(request, tpl, user_context):
 def _render_error(request, errortpl="error", user_context=None):
     if user_context is None:
         user_context = {}
-    return render_to_response(
-        "common/%s.html" % errortpl, user_context,
-        context_instance=template.RequestContext(request)
+    return render(
+        request, "common/%s.html" % errortpl, user_context
     )
 
 

modoboa/templates/common/error.html

@@ -1,4 +1,4 @@
-{% extends "nlayout.html" %}
+{% extends "layout_simple.html" %}
 {% load i18n %}
 {% block content %}
 <div class="alert alert-error"><strong>{% trans "Error:" %}</strong> {{ error }}</div>