Mocking the Client Service

[kaungsoe]

Question Checklist

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• I read the Contribution Guidelines
• I read README
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Question Subject

Mocking the client service

Question Description

Here is the client service from example.

public protocol Routeguide_RouteGuideClientProtocol {
  func getFeature(_ request: Routeguide_Point, callOptions: CallOptions?) -> UnaryCall<Routeguide_Point, Routeguide_Feature>
  func listFeatures(_ request: Routeguide_Rectangle, callOptions: CallOptions?, handler: @escaping (Routeguide_Feature) -> Void) -> ServerStreamingCall<Routeguide_Rectangle, Routeguide_Feature>
  func recordRoute(callOptions: CallOptions?) -> ClientStreamingCall<Routeguide_Point, Routeguide_RouteSummary>
  func routeChat(callOptions: CallOptions?, handler: @escaping (Routeguide_RouteNote) -> Void) -> BidirectionalStreamingCall<Routeguide_RouteNote, Routeguide_RouteNote>
}

What I want to do is, create mock object for this service.

class Routeguide_RouteGuideClientMock: Routeguide_RouteGuideClientProtocol {
    
    func getFeature(_ request: Routeguide_Point, callOptions: CallOptions?) -> UnaryCall<Routeguide_Point, Routeguide_Feature> {
        // return mock object directely
    }
    
    func listFeatures(_ request: Routeguide_Rectangle, callOptions: CallOptions?, handler: @escaping (Routeguide_Feature) -> Void) -> ServerStreamingCall<Routeguide_Rectangle, Routeguide_Feature> {
        
    }
    
    func recordRoute(callOptions: CallOptions?) -> ClientStreamingCall<Routeguide_Point, Routeguide_RouteSummary> {
        
    }
    
    func routeChat(callOptions: CallOptions?, handler: @escaping (Routeguide_RouteNote) -> Void) -> BidirectionalStreamingCall<Routeguide_RouteNote, Routeguide_RouteNote> {
        
    }
}

But there is no public initialiser. Is there any way I can accomplish it. Thanks.

[MrMage]

On the old cgrpc branch, we actually had special "test stub" implementations of these classes to make mocking even easier. Unfortunately, we have not gotten around yet to prioritizing this for the new NIO branch. @glbrntt do you think this is something we could prioritize?

[glbrntt]

We should prioritise this, yes. I don't think I'll have time to get to it this week though (next week hopefully).

Some initial thoughts:

• We can probably do this without having to construct a channel at all; we'll still need an event loop (EmbeddedEventLoop might be okay here)
• Some of the features available on the call object won't be available: the http/2 stream channel future and RPC cancellation to name some; maybe that's not an issue, however.

[MrMage]

FYI, #800 should solve this when done.

[glbrntt]

Resolved by #855, #864, and #870