ServiceUnavailableRetryHandler

Service Unavailable Retry Handler

Summary

The Service Unavailable Retry handler/filter automatically waits for a specified interval and retrys the request when a 503 (Service Unavailable) response is received from the server.

A maximum wait interval can be specified, if the server specifies a retry after time that is greater than the wait interval then the 503 response is returned to the caller so it can decide how to proceed. Specify TimeSpan.Zero to indicate there is no maximum wait time. The maximum wait time is also used as a default if the server does not provide a retry after header.

A maximum number of retries can also be specified.

Conditional Support

Conditional logic is NOT currently supported. All 503 responses will result in a wait & retry.

Sample

This sample configures an HTTP client instance to use the Service Unavailable Retry handler.

// Configure the http client
var handler = new ServiceUnavailableRetryHandler(
    new System.Net.Http.HttpClientHandler(),
    3, // Max retry attempts
    TimeSpan.FromSeconds(30) // Max wait interval per attempt
);
var client = new System.Net.Http.HttpClient(handler);

// Make a request that will be retried if a 503 response is received.
var result = await client.GetAsync("https://t.co/YJ9y1xD2be");