Redirect to Checkmate error pages

requirements.in

@@ -1,7 +1,6 @@
 h_vialib
 uwsgi
 pywb
-jinja2
 whitenoise
 newrelic
 h-checkmatelib

requirements.txt

@@ -17,11 +17,11 @@ fakeredis==0.16.0         # via pywb
 future==0.18.2            # via h-checkmatelib
 gevent==1.4.0             # via pywb
 greenlet==0.4.16          # via gevent
-h-checkmatelib==1.0.2     # via -r requirements.in
+h-checkmatelib==1.0.3     # via -r requirements.in
 h-vialib==1.0.0           # via -r requirements.in
 idna==2.10                # via requests, tldextract
 importlib-metadata==2.0.0  # via jsonschema
-jinja2==2.11.2            # via -r requirements.in, pywb
+jinja2==2.11.2            # via pywb
 jsonschema==3.2.0         # via h-checkmatelib
 markupsafe==1.1.1         # via jinja2
 newrelic==5.22.1.152      # via -r requirements.in

tests/unit/viahtml/views/blocklist_test.py

@@ -2,7 +2,6 @@
 
 import pytest
 from checkmatelib.exceptions import CheckmateException
-from h_matchers import Any
 
 from viahtml.views.blocklist import BlocklistView
 
@@ -48,25 +47,17 @@ def test_if_a_call_to_checkmate_fails_it_does_nothing(self, view, start_response
 
         assert result is None
 
-    @pytest.mark.parametrize(
-        "block_reason,expected_heading",
-        (
-            ("malicious", "Deceptive site ahead"),
-            ("publisher-blocked", "Content not available"),
-            ("anything-else-at-all", "Content cannot be annotated"),
-        ),
-    )
-    def test_blocking(self, view, block_reason, start_response, expected_heading):
-        view.checkmate.check_url.return_value.reason_codes = [block_reason]
+    def test_blocking(self, view, start_response):
+        blocked_response = view.checkmate.check_url.return_value
+        blocked_response.reason_codes = ["some_reason"]
 
         result = view("/proxy/http://example.com", {}, start_response)
 
         start_response.assert_called_once_with(
-            "403 Forbidden", [("Content-Type", "text/html; charset=utf-8")]
+            "307 Temporary Redirect", [("Location", blocked_response.presentation_url)]
         )
 
-        assert result == Any.list.of_size(1)
-        assert expected_heading in result[0].decode("utf-8")
+        assert result == []
 
     @pytest.fixture
     def start_response(self):

viahtml/views/blocklist.py

@@ -1,12 +1,9 @@
 """The blocklist view."""
 
-import os
 import re
 from logging import getLogger
 
 from checkmatelib import CheckmateClient, CheckmateException
-from jinja2 import Environment, FileSystemLoader, select_autoescape
-from pkg_resources import resource_filename
 
 LOG = getLogger(__name__)
 
@@ -16,13 +13,6 @@ class BlocklistView:
 
     PROXY_PATTERN = re.compile(r"^/proxy/(?:[a-z]{2}_/)?(.*)$")
 
-    JINJA_ENV = Environment(
-        loader=FileSystemLoader(
-            os.path.abspath(resource_filename("viahtml", "templates"))
-        ),
-        autoescape=select_autoescape(["html", "xml"]),
-    )
-
     def __init__(self, checkmate_host):
         self.checkmate = CheckmateClient(checkmate_host)
 
@@ -49,16 +39,16 @@ def __call__(self, path, environ, start_response):
             return None
 
         try:
-            hits = self.checkmate.check_url(url, allow_all=True)
+            blocked = self.checkmate.check_url(url, allow_all=True)
         except CheckmateException as err:
             LOG.warning("Failed to check URL against Checkmate: %s", err)
             return None
 
-        if not hits:
+        if not blocked:
             return None
 
-        start_response("403 Forbidden", [("Content-Type", "text/html; charset=utf-8")])
-
-        template = self.JINJA_ENV.get_template("viahtml/blocked_page.html.jinja2")
-        content = template.render(reason=hits.reason_codes[0], url_to_annotate=url)
-        return [content.encode("utf-8")]
+        # Redirect the user to the presentation URL given to us by Checkmate
+        start_response(
+            "307 Temporary Redirect", [("Location", blocked.presentation_url)]
+        )
+        return []