Resilience & Error Handling Overview

EverTask provides comprehensive resilience features to help you build fault-tolerant background tasks that can recover from transient failures automatically.

Key Features

Retry Policies

Automatically retry failed tasks with configurable policies. Choose from built-in linear retry, implement custom exponential backoff, or integrate with Polly for advanced resilience patterns.

Learn more: Retry Policies

Exception Filtering

Configure which exceptions should trigger retries and which should fail immediately. Prevent wasting retry attempts on permanent errors while handling transient failures gracefully.

Learn more: Exception Filtering

OnRetry Callbacks

Get visibility into retry attempts with lifecycle callbacks. Track metrics, implement circuit breaker patterns, and debug intermittent failures.

Learn more: Retry Callbacks

Timeout Management

Prevent runaway tasks with flexible timeout configuration at global, per-handler, and per-queue levels.

Learn more: Timeout Management

Cancellation Support

Implement cooperative cancellation for graceful shutdown and resource cleanup using CancellationTokens.

Learn more: Cancellation Tokens

Graceful Shutdown

Handle application restarts gracefully with automatic task recovery and progress tracking.

Learn more: Graceful Shutdown

Error Observation

React to errors using lifecycle hooks for alerting, telemetry, and compensation workflows.

Learn more: Error Observation

Quick Examples

Basic Retry Policy

builder.Services.AddEverTask(opt =>
{
    // 3 attempts with 500ms delay between retries
    opt.SetDefaultRetryPolicy(new LinearRetryPolicy(3, TimeSpan.FromMilliseconds(500)));
});

Exception Filtering

public class DatabaseTaskHandler : EverTaskHandler<DatabaseTask>
{
    public override IRetryPolicy? RetryPolicy => new LinearRetryPolicy(5, TimeSpan.FromSeconds(2))
        .HandleTransientDatabaseErrors(); // Only retry database-related errors
}

Timeout Configuration

public class QuickTaskHandler : EverTaskHandler<QuickTask>
{
    public override TimeSpan? Timeout => TimeSpan.FromSeconds(30);
}

Cancellation Token Usage

public override async Task Handle(MyTask task, CancellationToken cancellationToken)
{
    foreach (var item in task.Items)
    {
        cancellationToken.ThrowIfCancellationRequested();
        await ProcessItemAsync(item, cancellationToken);
    }
}

Next Steps

Start with Retry Policies to learn the basics, then explore:

• Exception Filtering - Fail-fast on permanent errors
• Retry Callbacks - Track and debug retry attempts
• Timeout Management - Prevent runaway tasks
• Best Practices - Build robust, resilient systems