From 7c3abe7ba738de25c981624bbed23bcabf4a73ab Mon Sep 17 00:00:00 2001
From: Jakub Warmuz <jakub@warmuz.org>
Date: Wed, 17 Dec 2014 11:44:31 +0100
Subject: [PATCH] IDisplay

---
 letsencrypt/client/display.py    | 42 +++++++-------------------------
 letsencrypt/client/interfaces.py | 31 +++++++++++++++++++++++
 2 files changed, 40 insertions(+), 33 deletions(-)

diff --git a/letsencrypt/client/display.py b/letsencrypt/client/display.py
index 700d69f8e..5fff122b9 100644
--- a/letsencrypt/client/display.py
+++ b/letsencrypt/client/display.py
@@ -1,46 +1,20 @@
 import textwrap
 
 import dialog
+import zope.interface
+
+from letsencrypt.client import interfaces
 
 
 WIDTH = 72
 HEIGHT = 20
 
 
-class Display(object):
-    """Generic display."""
-
-    def generic_notification(self, message):
-        raise NotImplementedError()
-
-    def generic_menu(self, message, choices, input_text=""):
-        raise NotImplementedError()
-
-    def generic_input(self, message):
-        raise NotImplementedError()
-
-    def generic_yesno(self, message, yes_label="Yes", no_label="No"):
-        raise NotImplementedError()
-
-    def filter_names(self, names):
-        raise NotImplementedError()
-
-    def success_installation(self, domains):
-        raise NotImplementedError()
-
-    def display_certs(self, certs):
-        raise NotImplementedError()
-
-    def confirm_revocation(self, cert):
-        raise NotImplementedError()
-
-    def more_info_cert(self, cert):
-        raise NotImplementedError()
-
-
-class NcursesDisplay(Display):
+class NcursesDisplay(object):
+    zope.interface.implements(interfaces.IDisplay)
 
     def __init__(self, width=WIDTH, height=HEIGHT):
+        super(NcursesDisplay, self).__init__()
         self.dialog = dialog.Dialog()
         self.width = width
         self.height = height
@@ -112,9 +86,11 @@ class NcursesDisplay(Display):
         self.dialog.msgbox(text, width=self.width, height=self.height)
 
 
-class FileDisplay(Display):
+class FileDisplay(object):
+    zope.interface.implements(interfaces.IDisplay)
 
     def __init__(self, outfile):
+        super(FileDisplay, self).__init__()
         self.outfile = outfile
 
     def generic_notification(self, message):
diff --git a/letsencrypt/client/interfaces.py b/letsencrypt/client/interfaces.py
index cbe71cd4c..8f7f10e97 100644
--- a/letsencrypt/client/interfaces.py
+++ b/letsencrypt/client/interfaces.py
@@ -103,6 +103,37 @@ class IConfigurator(zope.interface.Interface):
         """Cleanup configuration changes from challenge."""
 
 
+class IDisplay(zope.interface.Interface):
+    """Generic display."""
+
+    def generic_notification(message):
+        pass
+
+    def generic_menu(message, choices, input_text=""):
+        pass
+
+    def generic_input(message):
+        pass
+
+    def generic_yesno(message, yes_label="Yes", no_label="No"):
+        pass
+
+    def filter_names(names):
+        pass
+
+    def success_installation(domains):
+        pass
+
+    def display_certs(certs):
+        pass
+
+    def confirm_revocation(cert):
+        pass
+
+    def more_info_cert(cert):
+        pass
+
+
 class IValidator(object):
     """Configuration validator."""