FakeCloud 0.44.10

fakecloud

C#/.NET client SDK for fakecloud — a local AWS cloud emulator.

Provides typed access to the fakecloud introspection and simulation API (/_fakecloud/* endpoints), letting you inspect emulator state and trigger time-based processors in tests.

Requires .NET 8 or later (targets net8.0 and net10.0). Uses HttpClient and System.Text.Json, with no third-party dependencies.

Installation

dotnet add package FakeCloud

Or in your test project file:

<ItemGroup>
  <PackageReference Include="FakeCloud" Version="0.44.1" />
</ItemGroup>

Quick start

using FakeCloud;

var fc = new FakeCloudClient("http://localhost:4566");

// Check server health
var health = await fc.HealthAsync();
Console.WriteLine($"{health.Version} {string.Join(",", health.Services!)}");

// Reset all state between tests
await fc.ResetAsync();

// Inspect SES emails sent during a test
var emails = (await fc.Ses.GetEmailsAsync()).Emails;
Console.WriteLine($"Sent {emails!.Count} emails");

// Inspect SNS messages
var messages = (await fc.Sns.GetMessagesAsync()).Messages;

// Inspect SQS messages across all queues
var queues = (await fc.Sqs.GetMessagesAsync()).Queues;

// Advance DynamoDB TTL processor
int expired = (await fc.DynamoDb.TickTtlAsync()).ExpiredItems;

// Advance S3 lifecycle processor
int expiredObjects = (await fc.S3.TickLifecycleAsync()).ExpiredObjects;

All methods are async and accept an optional trailing CancellationToken.

API reference

FakeCloudClient

var fc = new FakeCloudClient();                        // defaults to http://localhost:4566
var fc = new FakeCloudClient("http://localhost:4566"); // explicit base URL

fc.Lambda

fc.Ses

fc.Sns

fc.Sqs

fc.Events

fc.Scheduler

fc.Glue

fc.CloudWatch

fc.Firehose

fc.S3

fc.DynamoDb

fc.SecretsManager

fc.Cognito

fc.Rds

fc.ElastiCache

fc.Ec2

fc.Ecr

fc.Logs

fc.StepFunctions

fc.ApiGatewayV2

fc.Bedrock

fc.BedrockAgent

fc.BedrockAgentRuntime

fc.Ecs

fc.Elbv2

fc.Route53

fc.Acm

fc.ApplicationAutoScaling

fc.Athena

fc.Organizations

fc.Ssm

fc.Kms

fc.WafV2

fc.CloudFront

Full test loop — asserting on Bedrock calls

using FakeCloud;

var fc = new FakeCloudClient();
var modelId = "anthropic.claude-3-haiku-20240307-v1:0";

// per-test setup
await fc.ResetAsync();

// Prime prompt-conditional responses
await fc.Bedrock.SetResponseRulesAsync(modelId, new[]
{
    new BedrockResponseRule("buy now", """{"label":"spam"}"""),
    new BedrockResponseRule(null, """{"label":"ham"}"""), // catch-all
});

await Classify("hello friend");           // user code calls Bedrock
await Classify("buy now cheap pills");

var invocations = (await fc.Bedrock.GetInvocationsAsync()).Invocations!;
Assert.Equal(2, invocations.Count);
Assert.Contains("ham", invocations[0].Output);
Assert.Contains("spam", invocations[1].Output);

Error handling

All methods throw FakeCloudException on non-2xx responses:

using FakeCloud;

try
{
    await fc.Cognito.ConfirmUserAsync(new ConfirmUserRequest("pool-1", "nobody"));
}
catch (FakeCloudException err)
{
    Console.WriteLine(err.Status); // 404
    Console.WriteLine(err.Body);   // "user not found"
}

Local development

# Build fakecloud (from repo root)
cargo build --release

# Run unit tests
cd sdks/dotnet
dotnet test

# Run E2E tests against the freshly-built binary
../../target/release/fakecloud &
dotnet test

The E2E tests in tests/FakeCloud.Tests/E2ETests.cs no-op when no server is reachable at http://localhost:4566 (override with FAKECLOUD_ENDPOINT).