PollyDapper 1.0.1

PollyDapper

Polly v8 resilience pipelines for Dapper — wrap QueryAsync, ExecuteAsync, and other Dapper calls with retry, timeout, circuit-breaker, and more using a single ResilientDbConnection decorator. Zero changes to your SQL.

var resilient = connection.WithPolly(pipeline =>
    pipeline
        .AddRetry(new RetryStrategyOptions
        {
            MaxRetryAttempts = 3,
            Delay = TimeSpan.FromMilliseconds(200),
            ShouldHandle = new PredicateBuilder().Handle<Exception>(),
        })
        .AddTimeout(TimeSpan.FromSeconds(5)));

var orders = await resilient.QueryAsync<Order>("SELECT * FROM Orders WHERE CustomerId = @Id", new { Id = id });

Every Dapper call is now automatically wrapped with retry + timeout — zero changes to existing SQL.

Why PollyDapper?

Dapper is intentionally minimal — it gives you no interception point for cross-cutting concerns like retry or timeout. PollyDapper adds that layer cleanly.

Installation

dotnet add package PollyDapper

Targets net6.0, net8.0, and net9.0.

Dependencies: Polly.Core 8.*, Dapper 2.*, Microsoft.Extensions.DependencyInjection.Abstractions 8.*

Quick start

1. Inline pipeline (ad-hoc usage)

using PollyDapper;

var resilient = connection.WithPolly(pipeline =>
    pipeline.AddRetry(new RetryStrategyOptions
    {
        MaxRetryAttempts = 3,
        Delay = TimeSpan.FromMilliseconds(200),
        BackoffType = DelayBackoffType.Exponential,
        ShouldHandle = new PredicateBuilder().Handle<Exception>(),
    }));

var users = await resilient.QueryAsync<User>("SELECT * FROM Users");

2. Pre-built pipeline

var pipeline = new ResiliencePipelineBuilder()
    .AddRetry(new RetryStrategyOptions { MaxRetryAttempts = 3 })
    .AddTimeout(TimeSpan.FromSeconds(10))
    .Build();

var resilient = connection.WithPolly(pipeline);
var count = await resilient.ExecuteScalarAsync<int>("SELECT COUNT(*) FROM Orders");

3. Dependency injection

// Program.cs
builder.Services.AddPollyDapper(pipeline =>
    pipeline
        .AddRetry(new RetryStrategyOptions { MaxRetryAttempts = 3 })
        .AddTimeout(TimeSpan.FromSeconds(5)));

// Repository
public class OrderRepository(IDbConnection db, ResiliencePipeline pipeline)
{
    public Task<IEnumerable<Order>> GetAllAsync() =>
        db.WithPolly(pipeline).QueryAsync<Order>("SELECT * FROM Orders");

    public Task<int> InsertAsync(Order order) =>
        db.WithPolly(pipeline).ExecuteAsync(
            "INSERT INTO Orders (CustomerId, Total) VALUES (@CustomerId, @Total)", order);
}

Supported methods

Pipeline order

Polly strategies are applied outer-to-inner (left-to-right). The recommended order is:

[Timeout] → [Retry] → [Circuit Breaker] → [Dapper]

pipeline
    .AddTimeout(TimeSpan.FromSeconds(10))    // 1. Overall deadline
    .AddRetry(retryOptions)                  // 2. Retry on failure
    .AddCircuitBreaker(cbOptions)            // 3. Open circuit if overloaded

ASP.NET Core example

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddScoped<IDbConnection>(_ =>
    new SqlConnection(builder.Configuration.GetConnectionString("Default")));

builder.Services.AddPollyDapper(pipeline =>
    pipeline
        .AddRetry(new RetryStrategyOptions
        {
            MaxRetryAttempts = 3,
            Delay = TimeSpan.FromMilliseconds(100),
            BackoffType = DelayBackoffType.Exponential,
            ShouldHandle = new PredicateBuilder()
                .Handle<SqlException>(ex => ex.IsTransient),
        })
        .AddTimeout(TimeSpan.FromSeconds(30))
        .AddCircuitBreaker(new CircuitBreakerStrategyOptions
        {
            FailureRatio = 0.5,
            MinimumThroughput = 10,
            SamplingDuration = TimeSpan.FromSeconds(30),
            BreakDuration = TimeSpan.FromSeconds(15),
        }));

Related packages

Package	Downloads	Description
PollyEFCore		Polly v8 resilience for EF Core queries and SaveChanges
PollySqlClient		Polly v8 resilience for SQL Server and Azure SQL with SqlServerTransientErrors predicate
PollyMediatR		Polly v8 resilience pipelines for MediatR
PollyHealthChecks		ASP.NET Core health checks for Polly v8 circuit breakers
PollyOpenAI		Polly v8 resilience for OpenAI and Azure OpenAI — retry on 429, Retry-After, circuit breaker
PollyRedis		Polly v8 resilience for StackExchange.Redis
PollySignalR		Polly v8 exponential back-off reconnect policy for SignalR
PollyElasticsearch	Polly v8 for Elastic.Clients.Elasticsearch
PollyAzureKeyVault	Polly v8 for Azure Key Vault
PollyAzureEventHub	Polly v8 for Azure Event Hubs
PollySendGrid	Polly v8 for SendGrid
PollyMassTransit	Polly v8 for MassTransit
PollyAzureTableStorage	Polly v8 for Azure Table Storage
PollyMailKit	MailKit SMTP email client
PollyAzureQueueStorage	Azure Queue Storage QueueClient
PollyHangfire	Hangfire IBackgroundJobClient
PollyBackoff		Jitter, linear & custom backoff for Polly v8 retry
PollyChaos		Fault & latency injection (Simmy for Polly v8)

💼 Need .NET consulting?

The author of this package is available for consulting on Polly v8 resilience, Azure cloud architecture, and clean .NET design.

→ solidqualitysolutions.com · LinkedIn

License

MIT