From 6d58abf7a62edd89cfb21975a6fb4d62494ce003 Mon Sep 17 00:00:00 2001
From: sinwoobang <sinwoobang@gmail.com>
Date: Tue, 22 Dec 2015 18:44:45 +0900
Subject: [PATCH] Add new http status 451

---
 aiohttp/web_exceptions.py    | 13 +++++++++++++
 tests/test_web_exceptions.py |  7 +++++++
 2 files changed, 20 insertions(+)

diff --git a/aiohttp/web_exceptions.py b/aiohttp/web_exceptions.py
index adc8cbb3f3c..254f07319a2 100644
--- a/aiohttp/web_exceptions.py
+++ b/aiohttp/web_exceptions.py
@@ -45,6 +45,7 @@
     'HTTPPreconditionRequired',
     'HTTPTooManyRequests',
     'HTTPRequestHeaderFieldsTooLarge',
+    'HTTPUnavailableForLegalReasons',
     'HTTPServerError',
     'HTTPInternalServerError',
     'HTTPNotImplemented',
@@ -286,6 +287,18 @@ class HTTPRequestHeaderFieldsTooLarge(HTTPClientError):
     status_code = 431
 
 
+class HTTPUnavailableForLegalReasons(HTTPClientError):
+    status_code = 451
+
+    def __init__(self, link=None, *, headers=None, reason=None,
+                 body=None, text=None, content_type=None):
+        super().__init__(headers=headers, reason=reason,
+                         body=body, text=text, content_type=content_type)
+        if link:
+            self.headers['Link'] = '<%s>; rel="blocked-by"' % link
+            self.link = link
+
+
 ############################################################
 # 5xx Server Error
 ############################################################
diff --git a/tests/test_web_exceptions.py b/tests/test_web_exceptions.py
index b89c659e161..e84dc25a152 100644
--- a/tests/test_web_exceptions.py
+++ b/tests/test_web_exceptions.py
@@ -163,3 +163,10 @@ def test_empty_body_205():
 def test_empty_body_304():
     resp = web.HTTPNoContent()
     resp.body is None
+
+
+def test_link_header_451(buf, request):
+    resp = web.HTTPUnavailableForLegalReasons(link='http://warning.or.kr/')
+
+    assert 'http://warning.or.kr/' == resp.link
+    assert '<http://warning.or.kr/>; rel="blocked-by"' == resp.headers['Link']