AWS Declarative Endpoint Traits#

This document defines AWS declarative endpoint traits.

AWS Endpoints Overview#

An endpoint is used to connect programmatically to an AWS service. An endpoint is the URL of the entry point for an AWS web service.

Most AWS services are regional: they offer regional endpoints and the service's resources are independent of similar resources in other regions.

Region: Each region consists of multiple availability zones within a single geographic area. Regions themselves are isolated and independent from other regions.

Partition: AWS groups regions into partitions. Every region is in exactly one partition and each partition has one or more regions. AWS commercial Regions are in the aws partition, Regions in China are in the aws-cn partition, and AWS GovCloud Regions are in the aws-us-gov partition.

FIPS Endpoints: Some AWS services have endpoints that support Federal Information Processing Standard (FIPS) 140-2. For a list of FIPS endpoints, see FIPS endpoints by Service.

Dual stack Endpoints: Some AWS services offer dual stack endpoints, so that you can access them using either IPv4 or IPv6 requests. For a list of services that support dual stack endpoints, see AWS services that support IPv6.

`aws.endpoints#endpointsModifier` trait#

Summary: A meta-trait that marks a trait as an endpoint modifier. Traits that are marked with this trait are applied to service shapes or operation shapes to indicate how a client can resolve endpoints for that service or operation.
Trait selector: [trait|trait]
Value type: Annotation trait

The following example defines a service with standardRegionalEndpoints modified by the hypothetical fooExample endpoint modifier.

$version: "2"

namespace smithy.example

use aws.endpoints#endpointsModifier
use aws.endpoints#standardRegionalEndpoints

@endpointsModifier
@trait(selector: "service")
structure fooExample {}

@standardRegionalEndpoints
@fooExample
service MyService {
    version: "2020-04-02"
}

Because endpoint modification definitions are just specialized shapes, they can also support configuration settings.

$version: "2"
namespace smithy.example

use aws.endpoints#endpointsModifier
use aws.endpoints#standardRegionalEndpoints

@endpointsModifier
@trait(selector: "service")
structure endpointSuffix {
    suffix: String
}

@standardRegionalEndpoints
@endpointSuffix(suffix="-suffix")
service MyService {
    version: "2020-04-02"
}

`aws.endpoints#standardRegionalEndpoints` trait#

Summary

An endpoints modifier trait that indicates that a service's endpoints should be resolved using the standard AWS regional patterns:

Default: https://{service}.{region}.{dnsSuffix}
Fips: https://{service}-fips.{region}.{dnsSuffix}
Dualstack: https://{service}.{region}.{dualStackDnsSuffix}
Fips/Dualstack: https://{service}-fips.{region}.{dualStackDnsSuffix}

Trait selector

service

Trait value

A structure with the following properties:

Property	Type	Description
partitionSpecialCases	`map` of partition to PartitionSpecialCase object	A map of partition to partition special cases - endpoints for a partition that do not follow the standard patterns.
regionSpecialCases	`map` of region to RegionSpecialCase object	A map of region to regional special cases - endpoints for a region that do not follow the standard patterns.

Conflicts with: aws.endpoints#standardPartitionalEndpoints trait

Most AWS services are regionalized and are strongly encouraged to follow the standard endpoint patterns defined above for consistency, and to ensure that endpoints are forwards compatible, and that SDK updates are not required when the service launches in a new region or partition.

The following example defines a service that uses the standard regional endpoints:

$version: "2"

namespace smithy.example

use aws.endpoints#standardRegionalEndpoints

@standardRegionalEndpoints
service MyService {
    version: "2020-04-02"
}

While services are strongly encouraged to follow standard endpoint patterns, there are occasional exceptions and special cases. The following example defines a service that uses standard regional endpoints, but uses a non-standard pattern for FIPS endpoints in US GovCloud:

@standardRegionalEndpoints(
    partitionSpecialCases: {
        aws-us-gov: [
            {
                endpoint: "https://myservice.{region}.{dnsSuffix}",
                fips: true
            }
        ]
    }
)
service MyService {
    version: "2020-04-02"
}

`PartitionSpecialCase` object#

A PartitionSpecialCase defines the endpoint pattern to apply for all regional endpoints in the given partition. A PartitionSpecialCase object contains the following properties:

Property name	Type	Description
endpoint	`string`	Required. The special-cased endpoint pattern.
dualStack	`boolean`	When `true`, the special case will apply to dualstack endpoint variants.
fips	`boolean`	When `true`, the special case will apply to fips endpoint variants.

`RegionSpecialCase` object#

A RegionSpecialCase object contains the following properties:

Property name	Type	Description
endpoint	`string`	Required. The special-cased endpoint pattern.
dualStack	`boolean`	When `true`, the special case will apply to dualstack endpoint variants.
fips	`boolean`	When `true`, the special case will apply to fips endpoint variants.
signingRegion	`string`	Overrides the signingRegion used for this region.

`aws.endpoints#standardPartitionalEndpoints` trait#

Summary: An endpoints modifier trait that indicates that a service is partitional and a single endpoint should be resolved per partition.
Trait selector: service
Trait value: A structure with the following properties:

Property	Type	Description
endpointPatternType	`string`	Required The pattern type to use for the partition endpoint. This value can be set to `service_dnsSuffix` to use the `https://{service}.{dnsSuffix}` pattern or `service_region_dnsSuffix` to use `https://{service}.{region}.{dnsSuffix}`.
partitionEndpointSpecialCases	`map` of partition to PartitionEndpointSpecialCase object	A map of partition to partition endpoint special cases - partitions that do not follow the service's standard patterns or are located in a region other than the partition's `defaultGlobalRegion`.

Conflicts with: aws.endpoints#standardRegionalEndpoints trait

Partitional services (also known as "global" services) resolve a single endpoint per partition. That single endpoint is located in the partition's defaultGlobalRegion. Partitional services should follow one of two standard patterns:

service_dnsSuffix: https://{service}.{dnsSuffix}
service_region_dnsSuffix: https://{service}.{region}.{dnsSuffix}

The following example defines a partitional service that uses {service}.{dnsSuffix}:

$version: "2"

namespace smithy.example

use aws.endpoints#standardPartitionalEndpoints

@standardPartitionalEndpoints(endpointPatternType: "service_dnsSuffix")
service MyService {
    version: "2020-04-02"
}

Services should follow the standard patterns; however, occasionally there are special cases. The following example defines a partitional service that uses a special case pattern in the aws partition and uses a non-standard global region in the aws-cn partition:

@standardPartitionalEndpoints(
    endpointPatternType: "service_dnsSuffix",
    partitionEndpointSpecialCases: {
        aws: [{endpoint: "https://myservice.global.amazonaws.com"}],
        aws-cn: [{region: "cn-north-1"}]
    }
)
service MyService {
    version: "2020-04-02"
}

`PartitionEndpointSpecialCase` object#

A PartitionEndpointSpecialCase object contains the following properties:

Property name	Type	Description
endpoint	`string`	The special-cased endpoint pattern.
region	`string`	Override the `defaultGlobalRegion` used in this partition.
dualStack	`boolean`	When `true`, the special case will apply to dualstack endpoint variants.
fips	`boolean`	When `true`, the special case will apply to fips endpoint variants.

`aws.endpoints#dualStackOnlyEndpoints` trait#

Summary: An endpoints modifier trait that indicates that a service has only dual stack endpoints, does not support IPV4 only endpoints, and should not have the useDualStackEndpoint endpoint parameter. Dual stack endpoints support IPV4 and IPV6.
Trait selector: service
Trait value: Annotation trait

Adding the dualStackOnlyEndpoints trait to a service modifies the generation of endpoints from aws.endpoints#standardRegionalEndpoints trait or aws.endpoints#standardPartitionalEndpoints trait, removes the useDualStackEndpoint parameter, and defaults the behavior to dual stack for all partitions that support it.

The following example specifies a service that uses standard regional endpoint patterns and is dual stack only:

@standardRegionalEndpoints
@dualStackOnlyEndpoints
service MyService {
    version: "2020-04-02"
}

`aws.endpoints#rulesBasedEndpoints` trait#

Summary: An endpoints modifier trait that indicates that a service has hand written endpoint rules.
Trait selector: service
Trait value: Annotation trait

Services marked with the rulesBasedEndpoints trait have hand written endpoint rules that extend or replace their standard generated endpoint rules through an external mechanism. This trait marks the presence of hand written rules, which are added to the model by a transformer, but does not specify their behavior.

A service with rulesBasedEndpoints may extend the functionality of endpoint behavior described in the model through other endpoints modifier traits by modifying the generated EndpointRuleSet. The following example specifies a service that has standard regional endpoints extended with hand written rules:

@standardRegionalEndpoints
@rulesBasedEndpoints
service MyService {
    version: "2020-04-02"
}

Endpoint Pattern#

Endpoint Patterns SHOULD begin with a scheme of either http or https. When specifying special case endpoints in StandardRegionalEndpoints or StandardPartitionalEndpoints you may use an endpoint pattern such as https://{service}.{region}.{dnsSuffix} with the following pattern substitutions:

Pattern	Description
`{region}`	The region from the AWS::Region built-in.
`{service}`	The endpoint prefix from the service's endpointPrefix.
`{dnsSuffix}`	The dns suffix from the resolved partition's properties.
`{dualStackDnsSuffix}`	The dualStack dns suffix from the resolved partition's properties.

AWS Declarative Endpoint Traits#

AWS Endpoints Overview#

aws.endpoints#endpointsModifier trait#

aws.endpoints#standardRegionalEndpoints trait#

PartitionSpecialCase object#

RegionSpecialCase object#

aws.endpoints#standardPartitionalEndpoints trait#

PartitionEndpointSpecialCase object#

aws.endpoints#dualStackOnlyEndpoints trait#

aws.endpoints#rulesBasedEndpoints trait#