Serve message schemas.

Bodhi now serves its own message schemas at /message-schemas/v1/
so that the URLs referenced in the schemas will not return HTTP
404 codes.

fixes #3083

Signed-off-by: Randy Barlow <randy@electronsweatshop.com>

bodhi/server/services/schemas.py

@@ -0,0 +1,101 @@
+# Copyright © 2019 Red Hat, Inc.
+#
+# This file is part of Bodhi.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+"""Defines service endpoints for our message schemas."""
+
+import typing
+
+from cornice.resource import resource, view
+from pyramid import httpexceptions
+from pyramid.security import Allow, Everyone
+import pkg_resources
+
+from bodhi.server import security
+from bodhi.server.services import errors
+
+if typing.TYPE_CHECKING:  # pragma: no cover
+    import pyramid.util.Request  # noqa: 401
+
+
+READ_ACL = 'view_schemas'
+
+
+@resource(collection_path='/message-schemas/v1/', path='/message-schemas/v1/{topic}',
+          description='Message schemas')
+class MessageSchemasV1:
+    """
+    Defines resources for serving Bodhi's message schemas.
+
+    Operations acting on the collection are served at ``/message-schemas/v1/`` and operations acting
+    on a single schema are served at ``/message-schemas/v1/<topic>``.
+    """
+
+    def __init__(self, request: 'pyramid.util.Request', context: None = None):
+        """
+        Initialize the MessageSchemas resource.
+
+        Args:
+            request: The current web request.
+            context: Unused.
+        """
+        self.request = request
+
+    @staticmethod
+    def __acl__() -> typing.Iterable[typing.Tuple[str, str, str]]:
+        """
+        Define ACLs for the MessageSchemas resource.
+
+        Returns:
+            A list of ACLs for this Resource.
+        """
+        return [(Allow, Everyone, READ_ACL)]
+
+    @view(
+        accept=('application/json', 'text/json'), renderer='json',
+        cors_origins=security.cors_origins_ro, error_handler=errors.json_handler,
+        permission=READ_ACL)
+    def collection_get(self) -> typing.Iterable[str]:
+        """
+        List schemas.
+
+        This method responds to the ``/message-schemas/v1/`` endpoint.
+
+        Returns:
+            A list of message topics that Bodhi supports.
+        """
+        return [m.load().topic for m in pkg_resources.iter_entry_points('fedora.messages')
+                if m.module_name.startswith('bodhi.')]
+
+    @view(accept=('application/json', 'text/json'), renderer='json',
+          cors_origins=security.cors_origins_ro, error_handler=errors.json_handler,
+          permission=READ_ACL)
+    def get(self) -> dict:
+        """
+        Retrieve and render a single message schema.
+
+        This API responses to the ``/message_schemas/v1/<topic>`` endpoint.
+
+        Returns:
+            The requested message schema.
+        """
+        try:
+            return pkg_resources.load_entry_point(
+                'bodhi-messages', 'fedora.messages',
+                f"{self.request.matchdict['topic']}.v1").body_schema
+        except ImportError:
+            # The user has requested a topic that does not exist
+            raise httpexceptions.HTTPNotFound()

bodhi/tests/server/services/test_schemas.py

@@ -0,0 +1,84 @@
+# Copyright 2019 Red Hat, Inc.
+#
+# This file is part of Bodhi.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+"""This module contains tests for bodhi.server.services.schemas."""
+
+from pyramid import testing
+from pyramid import security
+
+from bodhi.messages.schemas.update import UpdateCommentV1
+from bodhi.server.services import schemas
+from bodhi.tests.server import base
+
+
+class TestMessageSchemasV1__init__(base.BaseTestCase):
+    """This class contains tests for the MessageSchemasV1.__init__() method."""
+    def test___init__(self):
+        """Assert the request is stored properly."""
+        request = testing.DummyRequest()
+
+        schemas_resource = schemas.MessageSchemasV1(request)
+
+        self.assertIs(schemas_resource.request, request)
+
+
+class TestMessageSchemasV1__acl__(base.BaseTestCase):
+    """This class contains tests for the MessageSchemasV1.__acl__() method."""
+    def test___acl__(self):
+        """Assert the permissions are correct."""
+        request = testing.DummyRequest()
+        schemas_resource = schemas.MessageSchemasV1(request)
+
+        acls = schemas_resource.__acl__()
+
+        self.assertEqual(acls, [(security.Allow, security.Everyone, 'view_schemas')])
+
+
+class TestMessageSchemasV1CollectionGet(base.BaseTestCase):
+    """This class contains tests for the MessageSchemasV1.collection_get() method."""
+    def test_get(self):
+        """Test with a GET request."""
+        response = self.app.get('/message-schemas/v1/', status=200, headers={'Accept': 'text/json'})
+
+        self.assertEqual(
+            set(response.json),
+            set([
+                'bodhi.buildroot_override.tag', 'bodhi.buildroot_override.untag',
+                'bodhi.compose.complete', 'bodhi.compose.composing', 'bodhi.compose.start',
+                'bodhi.compose.sync.done', 'bodhi.compose.sync.wait', 'bodhi.composer.start',
+                'bodhi.errata.publish', 'bodhi.repo.done', 'bodhi.update.comment',
+                'bodhi.update.complete.stable', 'bodhi.update.complete.testing',
+                'bodhi.update.edit', 'bodhi.update.eject', 'bodhi.update.karma.threshold.reach',
+                'bodhi.update.request.obsolete', 'bodhi.update.request.revoke',
+                'bodhi.update.request.stable', 'bodhi.update.request.testing',
+                'bodhi.update.request.unpush', 'bodhi.update.requirements_met.stable']))
+
+
+class TestMessageSchemasV1Get(base.BaseTestCase):
+    """This class contains tests for the MessageSchemasV1.get() method."""
+    def test_404(self):
+        """Assert a 404 error code when there isn't a message topic matching the URL."""
+        self.app.get('/message-schemas/v1/does-not-exist', status=404,
+                     headers={'Accept': 'text/json'})
+
+    def test_200(self):
+        """Assert correct behavior when an existing topic is requested."""
+        response = self.app.get(
+            '/message-schemas/v1/bodhi.update.comment',
+            status=200, headers={'Accept': 'text/json'})
+
+        self.assertEqual(response.json, UpdateCommentV1.body_schema)

docs/server_api/index.rst

@@ -45,6 +45,7 @@ sections of the API by following the links below:
    rest/overrides
    rest/packages
    rest/releases
+   rest/schemas
    rest/updates
    rest/users
 

docs/server_api/rest/schemas.rst

@@ -0,0 +1,10 @@
+Message schemas
+===============
+
+``cornice_sphinx`` does `not <https://github.com/Cornices/cornice.ext.sphinx/issues/15>`_ yet have
+the ability to render documentation for the ``/message-schemas/`` API, so we will include docblock
+documentation for that service here instead.
+
+
+.. autoclass:: bodhi.server.services.schemas.MessageSchemasV1
+   :members: