.NET SDK

Install and use the fakecloud SDK for C#/.NET tests (xUnit, NUnit, MSTest).

Install

dotnet add package FakeCloud

Or in your test project file:

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

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

Initialize

using FakeCloud;

var fc = new FakeCloudClient();                         // defaults to http://localhost:4566
var fc2 = new FakeCloudClient("http://localhost:5000"); // explicit base URL

All methods are async and accept an optional trailing CancellationToken.

Top-level

Method	Description
`HealthAsync()`	Server health check
`ResetAsync()`	Reset all service state
`ResetServiceAsync(service)`	Reset a single service
`CredentialsAsync()`	Fetch container/instance credentials (`GET /_fakecloud/credentials`)
`InstanceIdentityDocumentAsync()`	EC2 instance identity document (`/latest/dynamic/instance-identity/document`)
`DnsResolveAsync(name, type)`	Resolve a name against Route 53 records like the `--dns` resolver (`GET /_fakecloud/dns/resolve`)
`CreateAdminAsync(accountId, userName)`	Bootstrap an admin IAM user in an account

`fc.Lambda`

Method	Description
`GetInvocationsAsync()`	List recorded Lambda invocations
`GetWarmContainersAsync()`	List warm (cached) Lambda containers
`EvictContainerAsync(functionName)`	Evict a warm container
`DownloadFunctionCodeAsync(accountId, functionName, qualifier)`	Download the stored zip for a function version (`"latest"` or version)
`DownloadLayerContentAsync(accountId, layerName, version)`	Download the stored zip for a layer version

`fc.Ses`

Method	Description
`GetEmailsAsync()`	List all sent emails
`SimulateInboundAsync(req)`	Simulate an inbound email (receipt rules)
`GetMetricsAsync()`	Return aggregated send/bounce/complaint counters
`SetMailFromStatusAsync(identity, status)`	Force a MAIL FROM verification status
`GetDkimPublicKeyAsync(identity)`	Fetch the DKIM public key for an identity
`SetSandboxAsync(sandbox)`	Toggle the account-level sandbox flag
`GetBouncesAsync()`	List captured bounce events
`GetMessageInsightsAsync(messageId)`	Fetch Message Insights for a sent message
`GetSmtpSubmissionsAsync()`	List SMTP submission attempts
`GetEventDestinationDeliveriesAsync()`	List event-destination delivery records

`fc.Sns`

Method	Description
`GetMessagesAsync()`	List all published messages
`GetPendingConfirmationsAsync()`	List subscriptions pending confirmation
`ConfirmSubscriptionAsync(req)`	Confirm a pending subscription
`GetCertPemAsync()`	Return the PEM-encoded SNS signing cert used by message signature validators
`GetSmsMessagesAsync()`	List captured SMS messages SNS has "delivered"

`fc.Sqs`

Method	Description
`GetMessagesAsync()`	List all messages across all queues
`TickExpirationAsync()`	Tick the message expiration processor
`ForceDlqAsync(queueName)`	Force all messages to the queue's DLQ

`fc.Events`

Method	Description
`GetHistoryAsync()`	Get event history and delivery records
`FireRuleAsync(req)`	Fire an EventBridge rule manually

`fc.Scheduler`

Method	Description
`GetSchedulesAsync()`	List EventBridge Scheduler schedules
`FireScheduleAsync(group, name)`	Fire a single schedule immediately

`fc.Glue`

Method	Description
`GetJobsAsync()`	List registered Glue jobs
`GetJobRunsAsync(jobName?)`	List Glue job runs, optionally filtered
`GetCrawlersAsync()`	List Glue crawlers with state and targets

`fc.CloudWatch`

Method	Description
`GetAlarmsAsync()`	List metric and composite alarms
`GetMetricsAsync()`	List unique metric series with latest value

`fc.Firehose`

Method	Description
`GetDeliveryStreamsAsync()`	List delivery streams with type, status, encryption, dest count

`fc.S3`

Method	Description
`GetNotificationsAsync()`	List S3 notification events
`TickLifecycleAsync()`	Tick the lifecycle processor
`GetAccessPointsAsync()`	List S3 access points
`GetObjectLambdaResponsesAsync()`	List S3 Object Lambda responses captured

`fc.DynamoDb`

Method	Description
`TickTtlAsync()`	Tick the TTL processor
`SaveSnapshotAsync(dataPath)`	Save a DynamoDB snapshot on demand (`null` dataPath -> configured store)

`fc.SecretsManager`

Method	Description
`TickRotationAsync()`	Tick the rotation scheduler

`fc.Cognito`

Method	Description
`GetUserCodesAsync(poolId, username)`	Get confirmation codes for a user
`GetConfirmationCodesAsync()`	List all confirmation codes
`ConfirmUserAsync(req)`	Confirm a user (bypass verification)
`GetTokensAsync()`	List all active tokens
`ExpireTokensAsync(req)`	Expire tokens (optionally filtered)
`GetAuthEventsAsync()`	List auth events
`GetPreTokenGenInvocationsAsync()`	List PreTokenGeneration Lambda trigger invocations recorded by `InitiateAuth`
`MintAuthorizationCodeAsync(req)`	Mint a single-use OAuth2 authorization code (programmatic alternative to `/oauth2/authorize`)
`SetCompromisedPasswordsAsync(req)`	Seed the compromised-password list used by Advanced Security
`GetWebAuthnCredentialsAsync()`	List stored WebAuthn credentials

`fc.Rds`

Method	Description
`GetInstancesAsync()`	List RDS instances with runtime metadata
`LambdaInvokeAsync(req)`	Bridge endpoint for the PostgreSQL `aws_lambda` extension
`S3ImportAsync(req)`	Bridge endpoint for the PostgreSQL `aws_s3` extension (fetch object)
`S3ExportAsync(req)`	Bridge equivalent of `S3:PutObject` from inside the DB container

`fc.ElastiCache`

Method	Description
`GetClustersAsync()`	List ElastiCache cache clusters
`GetReplicationGroupsAsync()`	List ElastiCache replication groups
`GetServerlessCachesAsync()`	List ElastiCache serverless caches
`GetAclsAsync()`	List ElastiCache (Valkey/Redis) ACLs

`fc.Ec2`

Method	Description
`GetInstancesAsync()`	List EC2 instances with control-plane + runtime metadata
`GetInstanceNetworksAsync()`	Inspect each instance's backing network (Docker/Podman network or k8s NetworkPolicy), container IP, isolation backend, and whether security-group enforcement is active

`fc.Ecr`

Method	Description
`GetRepositoriesAsync()`	List ECR repositories
`GetImagesAsync()`	List all ECR images
`GetImagesForRepositoryAsync(repositoryName)`	Filter images by repository
`GetPullThroughRulesAsync()`	List configured pull-through cache rules

`fc.Logs`

Method	Description
`InjectAnomalyAsync(req)`	Inject a Log Anomaly Detector anomaly
`GetDeliveryConfigAsync()`	Persisted CloudWatch Logs delivery configurations
`GetFieldIndexesAsync(logGroupName)`	Parsed `Fields` from index policies on a log group

`fc.StepFunctions`

Method	Description
`GetExecutionsAsync()`	List all state machine execution history
`GetSyncExecutionsAsync()`	List synchronous (`StartSyncExecution`) results
`GetExecutionTreeAsync(arn)`	Full parent/child execution tree under an execution ARN
`EnqueueActivityTaskAsync(req)`	Push a synthetic activity task onto an activity worker queue

`fc.ApiGatewayV2`

Method	Description
`GetRequestsAsync()`	List all HTTP API requests received
`GetConnectionsAsync()`	List every active WebSocket connection tracked by API Gateway v2
`GetDomainNameMtlsInfoAsync(domainName)`	Fetch the mTLS truststore info for a custom domain (free-form JSON)
`WsUrl(apiId, stage?)`	Build the WebSocket URL for the given API id (default `$default` stage)

`fc.Bedrock`

Method	Description
`GetInvocationsAsync()`	List recorded Bedrock runtime invocations
`SetModelResponseAsync(modelId, text)`	Configure a single canned response for a model
`SetResponseRulesAsync(modelId, rules)`	Replace prompt-conditional response rules for a model
`ClearResponseRulesAsync(modelId)`	Clear all prompt-conditional response rules for a model
`QueueFaultAsync(rule)`	Queue a fault rule for the next N calls
`GetFaultsAsync()`	List currently queued fault rules
`ClearFaultsAsync()`	Clear all queued fault rules

`fc.BedrockAgent`

Method	Description
`GetAgentsAsync()`	List Bedrock Agent (control plane) agents

`fc.BedrockAgentRuntime`

Method	Description
`GetInvocationsAsync()`	List Bedrock Agent Runtime invocations

`fc.Ecs`

Method	Description
`GetClustersAsync()`	List ECS clusters
`GetTasksAsync(cluster?, status?)`	List tracked tasks, optionally filtered by cluster and status
`GetTaskAsync(taskId)`	Fetch a single task snapshot by task ID
`GetTaskLogsAsync(taskId)`	Captured stdout/stderr for a task plus its exit code if known
`ForceStopTaskAsync(taskId)`	SIGTERM (then SIGKILL after 10s) the task's running container
`MarkTaskFailedAsync(taskId, req)`	Flip a task to `STOPPED` without killing the container
`GetEventsAsync()`	Replay the lifecycle event log
`GetTaskMetadataAsync(taskArn)`	Aggregated v4 metadata dump for a task (by full ARN)
`GetCredentialsAsync(taskId)`	Return short-lived IAM credentials for a task (matches the wire shape ECS exposes)
`GetMetadataV3Async(taskId)`	Raw v3 task metadata document (free-form `JsonElement`)
`GetMetadataV4Async(taskId)`	Raw v4 task metadata document (free-form `JsonElement`)

`fc.Elbv2`

Method	Description
`GetLoadBalancersAsync()`	List ELBv2 load balancers (ALB/NLB/GWLB)
`GetTargetGroupsAsync()`	List ELBv2 target groups
`GetListenersAsync()`	List ELBv2 listeners
`GetRulesAsync()`	List ELBv2 listener rules
`FlushAccessLogsAsync()`	Force every buffered access-log + connection-log line to flush to S3 immediately
`GetWafCountsAsync()`	Return WAFv2 association/evaluation counts the ELBv2 service has accumulated

`fc.Route53`

Method	Description
`SetHealthCheckStatusAsync(id, status, reason?)`	Flip a health check between `Success` / `Failure` / `Timeout` / `DnsError` / `InsufficientDataPoints` / `Unknown`
`GetDnssecMaterialAsync(zoneId)`	Fetch DNSSEC material (DNSKEY + DS digest) for a hosted zone with at least one ACTIVE KSK
`SignDnssecAsync(zoneId, req)`	Sign an RRset under the zone's first ACTIVE KSK and return raw RRSIG fields

`fc.Acm`

Method	Description
`SetCertificateStatusAsync(arnOrId, status, reason?)`	Flip an ACM certificate's status synchronously (`ISSUED` / `FAILED` / `VALIDATION_TIMED_OUT`)
`ApproveCertificateAsync(arnOrId)`	Approve a `PENDING_VALIDATION` certificate (simulates the email click)
`GetCertificateChainInfoAsync(arnOrId)`	Inspect a stored cert's PEM block counts and byte sizes

`fc.ApplicationAutoScaling`

Method	Description
`TickAsync()`	Tick the Application Auto Scaling alarm evaluator
`ScheduledTickAsync()`	Tick the scheduled-action processor

`fc.Athena`

Method	Description
`GetNamedQueriesAsync()`	List every named query stored in the registry

`fc.Organizations`

Method	Description
`GetAccountsAsync()`	List every member account in the org (state, parent OU, tags, directly-attached SCPs)
`GetResponsibilityTransfersAsync()`	List every billing responsibility transfer (direction, status, active handshake)

`fc.Ssm`

Method	Description
`SetCommandStatusAsync(commandId, accountId, status)`	Flip the status of every invocation under a `SendCommand` command id
`FailCommandAsync(commandId, req?)`	Force a command (or specific invocation) into `Failed`
`GetParameterPolicyEventsAsync(accountId?)`	Return every parameter-policy event recorded for the account
`InjectSessionAsync(req)`	Drop a fake Session Manager session into state (bypassing `StartSession`)

`fc.Kms`

Method	Description
`GetUsageAsync()`	Return every recorded KMS data-plane invocation

`fc.WafV2`

Method	Description
`EvaluateAsync(request)`	Evaluate an arbitrary request payload against the stored WAFv2 rule set (free-form JSON)

`fc.CloudFront`

Method	Description
`GetDistributionsAsync()`	List CloudFront distributions with their `<id>.cloudfront.net` domain and serving state
`SetDistributionStatusAsync(distributionId, status)`	Flip a stored CloudFront Distribution's status (`Deployed` / `InProgress`) without waiting

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);   // error body from fakecloud
}

Example: full test loop

using FakeCloud;
using Xunit;

public class ClassifierTests : IAsyncLifetime
{
    private readonly FakeCloudClient _fc = new();
    private const string ModelId = "anthropic.claude-3-haiku-20240307-v1:0";

    public async Task InitializeAsync() => await _fc.ResetAsync();
    public Task DisposeAsync() => Task.CompletedTask;

    [Fact]
    public async Task ClassifierBranchesOnSpamVsHam()
    {
        await _fc.Bedrock.SetResponseRulesAsync(ModelId, new[]
        {
            new BedrockResponseRule("buy now", """{"label":"spam"}"""),
            new BedrockResponseRule(null, """{"label":"ham"}"""),
        });

        await Classify("hello friend");
        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);
    }

    [Fact]
    public async Task RetriesOnThrottlingException()
    {
        await _fc.Bedrock.QueueFaultAsync(new BedrockFaultRule(
            "ThrottlingException", "Rate exceeded", 429, 1, null, null));

        await Classify("hello");

        var invocations = (await _fc.Bedrock.GetInvocationsAsync()).Invocations!;
        Assert.Equal(2, invocations.Count);
        Assert.Contains("ThrottlingException", invocations[0].Error);
        Assert.Null(invocations[1].Error);
    }
}

Source

sdks/dotnet
Source README — always-current method list