How to enable read from StatefulService secondary replicas?

问题

Many of the official Service Fabric articles states that it should be possible to do read operations on secondary replicas, but I am unable to find a single code example that shows how to configure or use this advanced feature.

A good example would be to elaborate on this simple code sample: https://github.com/Azure-Samples/service-fabric-dotnet-getting-started/tree/master/Services/AlphabetPartitions

Where reads on secondaries are just HTTP Get operations.

I would like to use it as a way to scale out read intensive operations on StatefulServices.

回答1:

Found the answer in this article: How to use the Reliable Services communication APIs

It is possible to enable reads on secondary replicas using a parameter called listenOnSecondary in the constructor of the ServiceReplicaListener class.

The code sample found in the article is shown here, tweaked with named parameters:

protected override IEnumerable<ServiceReplicaListener> CreateServiceReplicaListeners()
{
    return new[]
    {
        new ServiceReplicaListener(context =>
            new MyCustomListener(context),
            "customReadonlyEndpoint",
            listenOnSecondary:true),

        new ServiceReplicaListener(context =>
            this.CreateServiceRemotingListener(context),
            "rpcPrimaryEndpoint",
            listenOnSecondary:false)
    };
}

来源：https://stackoverflow.com/questions/38152271/how-to-enable-read-from-statefulservice-secondary-replicas