The new `subtype.AttributeTransformerInterceptor` can return an error if
it fails to transform the attributes. This is mainly if invalid
attribute fields were included for a particular subtype. This error case
used to be checked in the grpc service handler functions. However, now
that it is happening in the interceptor, the `errorInterceptor` needs to
be moved up in the stack so that it will process the response of the new
transformation interceptor.
The `errorInterceptor` used to be after the `auditRequestInterceptor`
and prior to the `auditResponseInterceptor`, meaning that the
`auditResponseInterceptor` would have access to the result of the
`errorInterceptor`. But it seems the `auditRequestInterceptor` does not
use or need any of the headers set by the `errorInterceptor` so it
should be safe to move the `errorInterceptor`. This is important since
the `subtype.AttributeTransformerInterceptor` needs to be before the
audit interceptors in the stack to properly transform requests/responses
so they can be audited with the complete classification information.
This interceptor is responsible for maintaining compatability with the
JSON API with the change to the protobuf messages. The messages are
changing from a single attribue field to a oneof to explicitly associate
subtype attribute messages with the resource message. The interceptor
transforms the request prior to the auditReqeust interceptor, and
transforms the response after the auditResponse interceptor. This allows
the audit interceptors to use all the necessary classification
information when creating the audit events.
Previously, we initialized the listeners on the order they were provided
to us on the config file. In the future, we'll want to add new listener
purposes that depend on existing ones, so the init order needs to be
deterministic.
With this change, we'll initialize components in this order:
1. gRPC Server for Controller API.
2. All `api` HTTP Servers & gRPC Gateway Muxes.
3. `cluster` gRPC Server.
This commit introduces some renames for the sake of clarity as well as
improved test coverage:
- Removes `gatewayMux` reference from Controller object. This object was
misleading and is now uneeded.
- Removed uneeded `context.Context` arguments.
- Separates gRPC Server and gRPC Gateway concerns, both in functionality
and in naming. These two were conflated before.
- Added unit tests on `startListeners`.
* refactor (controller): Use a grpc server for the grpc-gateway
This starts a grpc server for the grpc-gateway. The new gateway
server uses an in-memory listener which also supports "dialing", so
the http proxy can connect to the in-memory listener.
This change allows us to use all grpc server features and was in part
motivated by a need for an interceptor of inbound requests. With that
said, having a "proper" grpc server for the gateway will provide a lot
more flexibility and capabilities moving forward.
The request context will still be verified via middleware in the
http proxy (see wrapHandlerWithCommonFuncs). This verified context
will be serialized into a protobuf and sent along to the grpc-gateway
via metadata where an interceptor will add the verified request
info to the request's context (see requestCtxInterceptor). The
interceptor will verify the serialized request info via a shared ticket
with it's companion in-memory http proxy. FYI: the ticket is simply
random base62 string (see db.NewPrivateId).
This change also necessitated a minor change to services. We need to
return an empty response instead of nil, nil when there are no errors
and the response is empty.
* refactor (handlers): Rename gRPC Gateway filter
Originally, this was called an OutgoingInterceptor, which is an
unfortunate name since it's not an interceptor. Now that we're
refactoring the gateway stuff and have proper interceptors, renaming
this should remove ambiguity
* refactor: Rework how 204 with empty msg is handled
Recent changes to grpc gateway has necessitated a change to how
204s are handled by the gateway
* tests (bats): Check status codes for delete operations
Timothy Messier
Hugo Vieira
Louis Ruch
Jim