How to get Dapr Service to Service Invocation to work when running under docker-compose

Question

When I try to use the Dapr SDK to call a service, I get the following error.

System.Net.Http.HttpRequestException: Connection refused (127.0.0.1:3500)
 ---> System.Net.Sockets.SocketException (111): Connection refused

Here are the settings for the service I'm trying to call in docker-compose:

 quest-service:
    image: ${DOCKER_REGISTRY-gamification}/quest-service:${TAG:-latest}
    environment:
      - ASPNETCORE_ENVIRONMENT=Development
      - ASPNETCORE_URLS=http://0.0.0.0:80
      - SeqServerUrl=http://seq
    build:
      context: .
      dockerfile: Services/LW.Gamification.QuestService/Dockerfile
    ports:
      - "5110:80"
      - "50010:50001"

  quest-service-dapr:
    image: "daprio/daprd:latest"
    command: ["./daprd",
      "-app-id", "Quest-Service",
      "-app-port", "80",
      "-components-path", "/Components",
      "-config", "/Configuration/config.yaml"
      ]
    volumes:
      - "./Dapr/Components/:/Components"
      - "./Dapr/Configuration/:/Configuration"
    depends_on:
      - quest-service
    network_mode: "service:quest-service"

The caller's settings are as follows:

player-service:
    image: ${DOCKER_REGISTRY-gamification}/player-service:${TAG:-latest}
    environment:
      - ASPNETCORE_ENVIRONMENT=Development
      - ASPNETCORE_URLS=http://0.0.0.0:80
      - SeqServerUrl=http://seq
    build:
      context: .
      dockerfile: Services/LW.Gamificaiton.PlayerService/Dockerfile
    ports:
      - "5109:80"
      - "50009:50001"

  player-service-dapr:
    image: "daprio/daprd:latest"
    command: ["./daprd",
      "-app-id", "Player-Service",
      "-app-port", "80",
      "-components-path", "/Components",
      "-config", "/Configuration/config.yaml"
      ]
    volumes:
      - "./Dapr/Components/:/Components"
      - "./Dapr/Configuration/:/Configuration"
    depends_on:
      - player-service
    network_mode: "service:player-service"

And here's the code that's not working:

            // demo service to service call
            var httpClient = DaprClient.CreateInvokeHttpClient("Quest-Service");
            var requestUri = $"api/v1/Quest";

            var result = await httpClient.GetFromJsonAsync<IEnumerable<string>>(requestUri);

PS: Messaging appears to be operating properly. 

I'm new to Dapr, so I'm sure I'm doing something foolish incorrectly, perhaps with ports. I'm just not sure!