Introduction
In this article, we explore the implementation of a Retry strategy using the Polly library version 8 in C#. The Retry strategy is a resilience mechanism that helps maintain system stability by repeatedly attempting to execute an operation after encountering errors, particularly transient ones.
Simple Example
Below is an example that demonstrates how to create a simple Retry strategy:
using Polly;
using Polly.Retry;
using System;
public class RetryExample
{
public static void Main()
{
// Retry with zero delay
RetryPolicy retryPolicy = Policy
.Handle<Exception>()
.Retry(3, onRetry: (exception, retryCount) =>
{
Console.WriteLine($"Retry attempt {retryCount}: {exception.Message}");
});
try
{
retryPolicy.Execute(() =>
{
// Code that might throw an exception
PerformOperation();
});
}
catch (Exception ex)
{
Console.WriteLine($"Operation failed after retries: {ex.Message}");
}
}
private static void PerformOperation()
{
// Code that might fail
}
}
Explanation
In this example, a policy for retrying is set up in case of exceptions. The `Retry` method specifies that up to three retry attempts should be made in case of an error. Additionally, an `onRetry` function is provided, which outputs the error message and the current retry attempt number after each failed attempt.
Conclusion
Using a Retry strategy in the Polly library is an effective way to manage transient errors in C# applications. Proper configuration of this method improves system stability and reduces disruptions caused by errors.