From 55f6347bbf1df4f0a8c161b1dbc935ab29124ace Mon Sep 17 00:00:00 2001
From: Florian VANDENBULCKE <fvandenbulcke@sii.fr>
Date: Fri, 5 Oct 2018 10:00:48 +0200
Subject: [PATCH] feat(useDnsServer): add field in admin view, use in resolver
 if defined. unit tests

---
 Dockerfile.dev                   |  5 +++--
 modoboa/admin/app_settings.py    |  9 +++++++++
 modoboa/admin/lib.py             |  5 +++++
 modoboa/admin/tests/test_mx.py   | 11 ++++++++++-
 modoboa/core/tests/test_views.py |  3 ++-
 5 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/Dockerfile.dev b/Dockerfile.dev
index 2621f68d3..33f195eb8 100644
--- a/Dockerfile.dev
+++ b/Dockerfile.dev
@@ -2,13 +2,14 @@ FROM python:3.6-alpine
 
 MAINTAINER Antoine Nguyen <tonio@ngyn.org>
 
-RUN apk add --update python3-dev libffi-dev gcc musl-dev libxml2-dev libxslt-dev \
+RUN apk add --update openssl python3-dev libffi-dev gcc musl-dev libxml2-dev libxslt-dev \
     libressl-dev jpeg-dev \
     && rm -rf /var/cache/apk/*
 
 WORKDIR /tmp
 COPY requirements.txt /tmp
-RUN pip install -r requirements.txt
+COPY test-requirements.txt /tmp
+RUN pip install -r requirements.txt -r test-requirements.txt
 
 RUN mkdir /code
 WORKDIR /code
diff --git a/modoboa/admin/app_settings.py b/modoboa/admin/app_settings.py
index cd1afa3e7..899ca7161 100644
--- a/modoboa/admin/app_settings.py
+++ b/modoboa/admin/app_settings.py
@@ -10,6 +10,7 @@ from django import forms
 from django.conf import settings
 from django.utils.encoding import force_text
 from django.utils.translation import ugettext as _, ugettext_lazy
+from django.forms.fields import GenericIPAddressField
 
 from modoboa.lib.form_utils import SeparatorField, YesNoField
 from modoboa.lib.sysutils import exec_cmd
@@ -78,6 +79,14 @@ class AdminParametersForm(param_forms.AdminParametersForm):
         )
     )
 
+    use_specific_dns_server = GenericIPAddressField(
+        label=ugettext_lazy("Use specific DNS server"),
+        required=False,
+        help_text=ugettext_lazy(
+            "Give specific DNS server instead of local server configuration"
+        )
+    )
+
     mbsep = SeparatorField(label=ugettext_lazy("Mailboxes"))
 
     handle_mailboxes = YesNoField(
diff --git a/modoboa/admin/lib.py b/modoboa/admin/lib.py
index 2b1819bed..84c7b39bb 100644
--- a/modoboa/admin/lib.py
+++ b/modoboa/admin/lib.py
@@ -175,6 +175,11 @@ def get_domain_mx_list(domain):
     """Return a list of MX IP address for domain."""
     result = []
     logger = logging.getLogger("modoboa.admin")
+    
+    use_specific_dns_server = param_tools.get_global_parameter("use_specific_dns_server")
+    if use_specific_dns_server :
+      dns.resolver.default_resolver.nameservers = [use_specific_dns_server]
+
     try:
         dns_answers = dns.resolver.query(domain, "MX")
     except dns.resolver.NXDOMAIN as e:
diff --git a/modoboa/admin/tests/test_mx.py b/modoboa/admin/tests/test_mx.py
index fea42ee53..fe8bd7d27 100644
--- a/modoboa/admin/tests/test_mx.py
+++ b/modoboa/admin/tests/test_mx.py
@@ -14,6 +14,7 @@ from django.utils.translation import ugettext as _
 
 from modoboa.core import factories as core_factories
 from modoboa.lib.tests import ModoTestCase
+from modoboa.parameters import tools as param_tools
 from . import utils
 from .. import factories, models
 from ..lib import get_domain_mx_list
@@ -107,7 +108,15 @@ class MXTestCase(ModoTestCase):
 
         management.call_command(
             "modo", "check_mx", "--domain", "toto.com")
-
+        
+    @mock.patch("socket.getaddrinfo")
+    @mock.patch.object(dns.resolver.Resolver, "query")
+    def test_get_domain_mx_list_with_dsn_server(self, mock_query, mock_getaddrinfo):
+      mock_query.side_effect = utils.mock_dns_query_result
+      mock_getaddrinfo.side_effect = utils.mock_ip_query_result
+      self.set_global_parameter("use_specific_dns_server","123.45.67.89")
+      get_domain_mx_list("does-not-exist.example.com")
+    
     @mock.patch("socket.getaddrinfo")
     @mock.patch.object(dns.resolver.Resolver, "query")
     def test_get_domain_mx_list_logging(self, mock_query, mock_getaddrinfo):
diff --git a/modoboa/core/tests/test_views.py b/modoboa/core/tests/test_views.py
index 221445348..84f4a5cd6 100644
--- a/modoboa/core/tests/test_views.py
+++ b/modoboa/core/tests/test_views.py
@@ -67,7 +67,8 @@ SETTINGS_SAMPLE = {
     "core-random_password_length": "8",
     "admin-create_alias_on_mbox_rename": False,
     "admin-dkim_keys_storage_dir": "",
-    "admin-dkim_default_key_length": 1024
+    "admin-dkim_default_key_length": 1024,
+    "admin-use_specific_dns_server": "193.43.55.67"
 }