Retry Policies

When creating modules, you can set a retry policy per module by overriding the RetryPolicy property. The retry policy uses a Polly policy, so if you've used Polly before you should be familiar with how to use it. If not, Polly have their own documentation that should help you with this.

Default

Retry policies are off by default, unless you set a default retry count on the PipelineOptions when you're using the PipelineHostBuilder. If you set a retry count, for example, 3, then all modules that fail will attempt to retry 3 times. This can be useful for when transient failures occur. You can of course combine this with overriding specific modules for more control.

Example

public class MyModule : Module
{
    protected override AsyncRetryPolicy<IDictionary<string, object>?> RetryPolicy { get; }
        = Policy<IDictionary<string, object>?>
            .Handle<HttpRequestException>()
            .WaitAndRetryAsync(5, i => TimeSpan.FromSeconds(i * i));

    protected override Task<IDictionary<string, object>?> ExecuteAsync(IPipelineContext context, CancellationToken cancellationToken)
    {
        // Do something
    }
}

Default Example

await PipelineHostBuilder.Create()
    .AddModule<Module1>()
    .AddModule<Module2>()
    .AddModule<Module3>()
    .ConfigurePipelineOptions((context, options) =>
    {
        options.DefaultRetryCount = 3;
    })
    .ExecutePipelineAsync();