Return domains for _find_domains_or_certname (#3937)

* Return domains for _find_domains_or_certname

* Revamp find_domains_or_certname

certbot/main.py

@@ -284,17 +284,26 @@ def _find_domains_or_certname(config, installer):
     """Retrieve domains and certname from config or user input.
     """
     domains = None
+    certname = config.certname
+    # first, try to get domains from the config
     if config.domains:
         domains = config.domains
-    elif not config.certname:
+    # if we can't do that but we have a certname, get the domains
+    # with that certname
+    elif certname:
+        domains = cert_manager.domains_for_certname(config, certname)
+
+    # that certname might not have existed, or there was a problem.
+    # try to get domains from the user.
+    if not domains:
         domains = display_ops.choose_names(installer)
 
-    if not domains and not config.certname:
+    if not domains and not certname:
         raise errors.Error("Please specify --domains, or --installer that "
                            "will help in domain names autodiscovery, or "
                            "--cert-name for an existing certificate name.")
 
-    return domains, config.certname
+    return domains, certname
 
 
 def _report_new_cert(config, cert_path, fullchain_path):

certbot/tests/main_test.py

@@ -159,10 +159,12 @@ class ObtainCertTest(unittest.TestCase):
         self.assertRaises(errors.ConfigurationError, self._call,
             ('certonly --webroot -d example.com -d test.com --cert-name example.com').split())
 
+    @mock.patch('certbot.cert_manager.domains_for_certname')
+    @mock.patch('certbot.display.ops.choose_names')
     @mock.patch('certbot.cert_manager.lineage_for_certname')
     @mock.patch('certbot.main._report_new_cert')
     def test_find_lineage_for_domains_new_certname(self, mock_report_cert,
-        mock_lineage):
+        mock_lineage, mock_choose_names, mock_domains_for_certname):
         mock_lineage.return_value = None
 
         # no lineage with this name but we specified domains so create a new cert
@@ -172,8 +174,10 @@ class ObtainCertTest(unittest.TestCase):
         self.assertTrue(mock_report_cert.call_count == 1)
 
         # no lineage with this name and we didn't give domains
-        self.assertRaises(errors.ConfigurationError, self._call,
-            ('certonly --webroot --cert-name example.com').split())
+        mock_choose_names.return_value = ["somename"]
+        mock_domains_for_certname.return_value = None
+        self._call(('certonly --webroot --cert-name example.com').split())
+        self.assertTrue(mock_choose_names.called)
 
 class FindDomainsOrCertnameTest(unittest.TestCase):
     """Tests for certbot.main._find_domains_or_certname."""
@@ -193,6 +197,14 @@ class FindDomainsOrCertnameTest(unittest.TestCase):
         # pylint: disable=protected-access
         self.assertRaises(errors.Error, main._find_domains_or_certname, mock_config, None)
 
+    @mock.patch('certbot.cert_manager.domains_for_certname')
+    def test_grab_domains(self, mock_domains):
+        mock_config = mock.Mock(domains=None, certname="one.com")
+        mock_domains.return_value = ["one.com", "two.com"]
+        # pylint: disable=protected-access
+        self.assertEqual(main._find_domains_or_certname(mock_config, None),
+            (["one.com", "two.com"], "one.com"))
+
 
 class RevokeTest(unittest.TestCase):
     """Tests for certbot.main.revoke."""