AWSim

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Services Overview ​

AWSim registers 60+ AWS services. All services share the same endpoint at http://localhost:4566.

The service is selected automatically from the X-Amz-Target header (for JSON/Query protocols) or the URL path (for REST protocols).

CBOR ​

AWSim accepts CBOR request bodies as well as JSON, in both dialects AWS uses:

DialectHow it arrivesWho sends it
Legacy AWS CBORContent-Type: application/x-amz-cbor-1.1 plus X-Amz-TargetAWS SDK for Java v1, which defaults to CBOR for DynamoDB and Kinesis
Smithy rpcv2Cborsmithy-protocol: rpc-v2-cbor, routed at /service/{Service}/operation/{Operation}Newer SDKs negotiating the Smithy protocol

Detection is per request and driven entirely by headers, so nothing changes for existing JSON clients. Responses are encoded in the same format as the request, with errors carrying the same __type code and x-amzn-RequestId header the JSON path returns.

Binary values round-trip correctly: a DynamoDB B or BS attribute arrives as a CBOR byte string and goes back out as one, rather than leaking the base64 form that the JSON protocols use internally.

Service Table ​

ServiceSigning NameProtocolPersistentOperationsDescription
ACMacmJSONYes—Certificate Manager
API Gatewayexecute-apiREST-JSONNo—REST API management and proxy (v1 + v2)
AppConfigappconfigREST-JSONYes20Feature flags & config delivery (control + data plane)
AppConfig Dataappconfig (appconfigdata)REST-JSONYes2Runtime polling: StartConfigurationSession + GetLatestConfiguration
Application Auto Scalingapplication-autoscalingJSONYes10Scalable targets and policies for ECS/Lambda/DynamoDB
AppSyncappsyncREST-JSONYes—GraphQL API
AthenaathenaJSONYes—SQL query service
BackupbackupREST-JSONYes17Backup vaults, plans, selections, jobs
BatchbatchREST-JSONYes—Batch compute jobs
BedrockbedrockREST-JSONNo—Foundation model management
Bedrock Runtimebedrock-runtimeREST-JSONNo—Foundation model invocation
Cloud MapservicediscoveryJSONYes17Service discovery: namespaces, services, instances
CloudFormationcloudformationQueryYes—Infrastructure as code
CloudFrontcloudfrontREST-XMLYes—CDN distributions
CloudTrailcloudtrailJSONYes—API audit log
CloudWatch LogslogsJSONYes—Log groups and streams
CloudWatch MetricsmonitoringQueryNo—Metrics and alarms
Cognito Identity Poolscognito-identityJSONYes—Federated identity
Cognito User Poolscognito-idpJSONYes—User authentication
ComprehendcomprehendJSONNo—Natural language processing
DataSyncdatasyncJSONYes—Data transfer service
DynamoDBdynamodbJSONYes57Key-value / document store
EC2ec2EC2-QueryYes—Virtual machines (partial)
ECRecrJSONYes—Container registry
ECSecsJSONYes—Container service
EFSelasticfilesystemREST-JSONYes19Elastic File System (file systems, mount targets, access points)
EKSeksREST-JSONYes—Kubernetes control plane
ELBelasticloadbalancingQueryYes—Load balancers
EventBridgeeventsJSONYes—Event routing
EventBridge PipespipesREST-JSONYes10Point-to-point source -> target integrations
EventBridge SchedulerschedulerREST-JSONYes—Scheduled tasks
FirehosefirehoseJSONYes—Streaming data delivery
GlacierglacierREST-JSONYes12Cold storage: vaults + archives + jobs
GlueglueJSONYes—Data catalog
IAMiamQueryYes—Identity and Access Management
Identity StoreidentitystoreJSONYes16Users, groups, group memberships (paired with SSO Admin)
KendrakendraJSONNo—Enterprise search
KinesiskinesisJSONNo—Data streaming
KMSkmsJSONYes28Key Management Service
LambdalambdaREST-JSONYes—Serverless function execution
MemoryDBmemorydbJSONYes18Redis-compatible clusters, users, ACLs, snapshots
MQmqREST-JSONYes14Amazon MQ brokers, users, configurations
OrganizationsorganizationsJSONYes—Account / OU / SCP management
PinpointmobiletargetingREST-JSONYes15Apps, endpoints, segments, campaigns (no real delivery)
PollypollyREST-JSONYes—Text-to-speech
QLDBqldbREST-JSONYes8Ledger metadata (control plane only)
RDSrdsQueryYes—Relational database metadata
Resource Groups Tagging APItaggingJSONYes8Cross-service resource discovery by tags
Route 53route53REST-XMLYes—DNS management
S3s3REST-XMLYes*44Object storage
Secrets ManagersecretsmanagerJSONYes—Secret storage
SESsesREST-JSON (v2) + Query (classic)Yes—Simple Email Service, both APIs
SNSsnsQueryYes21Simple Notification Service
SQSsqsQueryYes17Simple Queue Service
SSMssmJSONYes—Parameter Store and Systems Manager
SSO AdminssoJSONYes—IAM Identity Center admin
Step FunctionsstatesJSONYes—State machine orchestration
STSstsQueryNo—Security Token Service
Transfer FamilytransferJSONYes13SFTP/FTP servers, users, SSH keys (no actual listener)
WAFwafv2JSONYes—Web Application Firewall
X-RayxrayREST-JSONYes11Trace ingest, summaries, service graph

*S3 persists bucket and object metadata but not object data bytes.

OpenSearch ​

In addition to the AWS services, AWSim mounts an Elasticsearch-compatible REST API at /opensearch/. This is not a standard AWS service endpoint — see OpenSearch for details.

Protocol Notes ​

  • REST-XML — URL-based routing, XML request/response bodies (S3, Route 53, CloudFront)
  • REST-JSON — URL-based routing, JSON request/response bodies (Lambda, API Gateway, AppSync)
  • JSON — X-Amz-Target header routing, JSON bodies (DynamoDB, KMS, CloudWatch Logs)
  • Query — form-encoded request body with Action= parameter (SQS, SNS, IAM, EC2)

Detailed Service Pages ​

For operations lists, SDK examples, and limitations, see:

Released under MIT / Apache-2.0 License