Type Mapping

Enums in Collections

An enum surfaces as its ConstantClass only as a structure member's own type. As a list element, a map key, or a map value it is plain string:

This matches C2J. Typing an element as its ConstantClass would be a public-API divergence (Amazon.Lambda.Model.CreateFunctionRequest.Architectures and friends are List<string> in the shipped SDK). A paginator's items element type follows the same element rules (string for an enum, nullability per rule 3), so the flattened enumerable agrees with the List<T> property it reads from.

Constrained Shapes

Smithy allows constrained shapes (e.g. a string shape named Uuid with @length or @pattern). These do NOT get wrapper classes; they map to their underlying .NET type:

The constraints flow through to [AWSProperty] on the member that references the shape: Required from the member's @required; Min/Max from @length/@range on the member, else on the target (e.g. AuditEvents has @length(min:1, max:100), so PutAuditEventsRequest.AuditEvents gets [AWSProperty(Required=true, Min=1, Max=100)]); Sensitive from the target's @sensitive.

Error Shape Naming

Smithy error shapes often omit the Exception suffix. The rules (matching the current SDK):

• Ends with Exception → keep as-is (e.g. UnsupportedOperationException)
• Ends with Fault → replace Fault with Exception
• Otherwise → append Exception (e.g. ChannelNotFound → ChannelNotFoundException)

Error Shape Members

Error shapes have a message member in the Smithy model, but the generated exception class does not expose it as a property. The message is passed to System.Exception via the constructor and inherited as Exception.Message. The generator filters message out everywhere: the property set, the serialization block, and the unmarshaller alike.

Two base-class adjustments follow (matching the current SDK):

• A member named errorType is renamed to the property RequestErrorType (property name only; the wire name stays errorType) so it doesn't hide AmazonServiceException.ErrorType, whose type is the ErrorType enum rather than the member's own type.
• A member named Retryable is emitted with the new modifier, hiding AmazonServiceException.Retryable.

Independently of the exception-only rules, a member named Equals on any structure is emitted with new to hide object.Equals(object).

A response member named ContentLength is not shadowed but omitted from the response class entirely: AmazonWebServiceResponse already declares it and the unmarshaller assigns the inherited property. See sdk-conventions.

RequestId and ErrorCode get a narrower treatment than message. AmazonServiceException already declares them, so the generator emits no property (one would shadow the base). But unlike message they are not filtered from serialization or unmarshalling: C2J serializes and reads every modeled member except message, so the inherited property is still written to the serialization block and read from the error body. Every other member is emitted as-is, exactly as C2J does; one colliding with another inherited property (e.g. StatusCode) would hide it without new and fail the SDK's warnings-as-errors build, and no model has one.