fix: Add a default handler that returns a 404 in JSON format.

Tip-of-tree fiorix/cyclone supports custom error handlers via an
`error_handler` argument to `cyclone.web.Application`, but that hasn't
been published to PyPI yet. We work around this by registering a
catch-all handler that returns a 404 instead.

Closes #756.

autopush/base.py

@@ -1,9 +1,25 @@
+import json
 import uuid
 
 import cyclone.web
 from twisted.logger import Logger
 from twisted.python import failure
 
+status_codes = {
+    200: "OK",
+    201: "Created",
+    202: "Accepted",
+    400: "Bad Request",
+    401: "Unauthorized",
+    404: "Not Found",
+    413: "Payload Too Large",
+    418: "I'm a teapot",
+    500: "Internal Server Error",
+    503: "Service Unavailable",
+}
+DEFAULT_ERR_URL = ("http://autopush.readthedocs.io/en/latest/http.html"
+                   "#error-codes")
+
 
 class BaseHandler(cyclone.web.RequestHandler):
     """Base cyclone RequestHandler for autopush"""
@@ -77,3 +93,35 @@ def authenticate_peer_cert(self):
         self.set_header('WWW-Authenticate',
                         'Transport mode="tls-client-certificate"')
         self.finish()
+
+    def _write_response(self, status_code, errno=None, message=None,
+                        error=None, headers=None, url=DEFAULT_ERR_URL):
+        """Writes out a full JSON error and sets the appropriate status"""
+        self.set_status(status_code, reason=error)
+        error_data = dict(
+            code=status_code,
+            error=error or status_codes.get(status_code, ""),
+            more_info=url,
+        )
+        if errno:
+            error_data["errno"] = errno
+        if message:
+            error_data["message"] = message
+        self.write(json.dumps(error_data))
+        self.set_header("Content-Type", "application/json")
+        if headers:
+            for header in headers.keys():
+                self.set_header(header, headers.get(header))
+        self.finish()
+
+
+class DefaultHandler(BaseHandler):
+    """Unauthenticated catch-all handler that returns a 404 for
+    unknown paths. Cyclone matches handlers in order, so this handler
+    should be registered last."""
+
+    def authenticate_peer_cert(self):
+        pass
+
+    def prepare(self):
+        self._write_response(404)

autopush/main.py

@@ -12,6 +12,7 @@
 
 import autopush.db as db
 import autopush.utils as utils
+from autopush.base import DefaultHandler
 from autopush.logging import PushLogger
 from autopush.settings import AutopushSettings
 from autopush.ssl import AutopushSSLContextFactory
@@ -587,6 +588,7 @@ def endpoint_main(sysargs=None, use_files=True):
         (endpoint_paths['message'], MessageHandler, h_kwargs),
         (endpoint_paths['registration'], RegistrationHandler, h_kwargs),
         (endpoint_paths['logcheck'], LogCheckHandler, h_kwargs),
+        (r".*", DefaultHandler, h_kwargs),
     ],
         default_host=settings.hostname, debug=args.debug,
         log_function=skip_request_logging

autopush/tests/test_integration.py

@@ -30,6 +30,7 @@
 
 import autopush.db as db
 from autopush import __version__
+from autopush.base import DefaultHandler
 from autopush.db import (
     create_rotating_message_table,
     get_month,
@@ -397,6 +398,8 @@ def setUp(self):
             # GET /register/uaid => chid + endpoint
             (endpoint_paths['registration'], RegistrationHandler, h_kwargs),
             (endpoint_paths['logcheck'], LogCheckHandler, h_kwargs),
+
+            (r".*", DefaultHandler, h_kwargs),
         ],
             default_host=settings.hostname,
             log_function=skip_request_logging,

autopush/tests/test_web_base.py

@@ -175,7 +175,7 @@ def test_init_info(self, t):
         eq_(d["authorization"], "webpush token barney")
 
     def test_write_response(self):
-        self.base._write_response(400, 103, message="Fail",
+        self.base._write_response(400, errno=103, message="Fail",
                                   headers=dict(Location="http://a.com/"))
         self.status_mock.assert_called_with(400, reason=None)
 

autopush/web/base.py

@@ -11,23 +11,9 @@
 from autopush.base import BaseHandler
 from autopush.exceptions import InvalidRequest, RouterException
 
-status_codes = {
-    200: "OK",
-    201: "Created",
-    202: "Accepted",
-    400: "Bad Request",
-    401: "Unauthorized",
-    404: "Not Found",
-    413: "Payload Too Large",
-    418: "I'm a teapot",
-    500: "Internal Server Error",
-    503: "Service Unavailable",
-}
 # Older versions used "bearer", newer specification requires "webpush"
 AUTH_SCHEMES = ["bearer", "webpush"]
 PREF_SCHEME = "webpush"
-DEFAULT_ERR_URL = ("http://autopush.readthedocs.io/en/latest/http.html"
-                   "#error-codes")
 
 
 class ThreadedValidate(object):
@@ -153,26 +139,6 @@ def head(self, *args, **kwargs):
     #############################################################
     #                    Error Callbacks
     #############################################################
-    def _write_response(self, status_code, errno, message=None, error=None,
-                        headers=None,
-                        url=DEFAULT_ERR_URL):
-        """Writes out a full JSON error and sets the appropriate status"""
-        self.set_status(status_code, reason=error)
-        error_data = dict(
-            code=status_code,
-            errno=errno,
-            error=error or status_codes.get(status_code, ""),
-            more_info=url,
-        )
-        if message:
-            error_data["message"] = message
-        self.write(json.dumps(error_data))
-        self.set_header("Content-Type", "application/json")
-        if headers:
-            for header in headers.keys():
-                self.set_header(header, headers.get(header))
-        self.finish()
-
     def _validation_err(self, fail):
         """errBack for validation errors"""
         fail.trap(InvalidRequest)
@@ -181,7 +147,7 @@ def _validation_err(self, fail):
                       status_code=exc.status_code,
                       errno=exc.errno,
                       client_info=self._client_info)
-        self._write_response(exc.status_code, exc.errno,
+        self._write_response(exc.status_code, errno=exc.errno,
                              message="Request did not validate %s" %
                                      (exc.message or ""),
                              headers=exc.headers)
@@ -197,15 +163,16 @@ def _response_err(self, fail):
         self.log.failure(format=fmt, failure=fail,
                          status_code=500, errno=999,
                          client_info=self._client_info)
-        self._write_response(500, 999, message="An unexpected server error"
-                                               " occurred.")
+        self._write_response(500, errno=999,
+                             message="An unexpected server error"
+                                     " occurred.")
 
     def _overload_err(self, fail):
         """errBack for throughput provisioned exceptions"""
         fail.trap(ProvisionedThroughputExceededException)
         self.log.info(format="Throughput Exceeded", status_code=503,
                       errno=201, client_info=self._client_info)
-        self._write_response(503, 201,
+        self._write_response(503, errno=201,
                              message="Please slow message send rate")
 
     def _boto_err(self, fail):

autopush/web/log_check.py

@@ -35,7 +35,7 @@ def get(self, err_type=None, *args, **kwargs):
             self.log.error(format="Test Error Message",
                            status_code=418, errno=0,
                            client_info=self._client_info)
-            self._write_response(418, 999, message="ERROR:Success",
+            self._write_response(418, errno=999, message="ERROR:Success",
                                  error="Test Error")
         if 'crit' in err_type:
             try:
@@ -44,5 +44,6 @@ def get(self, err_type=None, *args, **kwargs):
                 self.log.failure(format="Test Critical Message",
                                  status_code=418, errno=0,
                                  client_info=self._client_info)
-                self._write_response(418, 999, message="FAILURE:Success",
+                self._write_response(418, errno=999,
+                                     message="FAILURE:Success",
                                      error="Test Failure")

autopush/web/registration.py

@@ -257,7 +257,7 @@ def _chid_not_found_err(self, fail):
         self.log.info(format="CHID not found in AWS.",
                       status_code=410, errno=106,
                       **self._client_info)
-        self._write_response(410, 106, message="Invalid endpoint.")
+        self._write_response(410, errno=106, message="Invalid endpoint.")
 
     #############################################################
     #                    Callbacks