DiscoverInstancesRevision - Amazon Cloud Map
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Discovers the increasing revision associated with an instance.

Request Syntax

{ "NamespaceName": "string", "ServiceName": "string" }

Request Parameters

For information about the parameters that are common to all actions, see Common Parameters.

The request accepts the following data in JSON format.


The HttpName name of the namespace. It's found in the HttpProperties member of the Properties member of the namespace.

Type: String

Length Constraints: Maximum length of 1024.

Required: Yes


The name of the service that you specified when you registered the instance.

Type: String

Pattern: ((?=^.{1,127}$)^([a-zA-Z0-9_][a-zA-Z0-9-_]{0,61}[a-zA-Z0-9_]|[a-zA-Z0-9])(\.([a-zA-Z0-9_][a-zA-Z0-9-_]{0,61}[a-zA-Z0-9_]|[a-zA-Z0-9]))*$)|(^\.$)

Required: Yes

Response Syntax

{ "InstancesRevision": number }

Response Elements

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.


The increasing revision associated to the response Instances list. If a new instance is registered or deregistered, the InstancesRevision updates. The health status updates don't update InstancesRevision.

Type: Long


For information about the errors that are common to all actions, see Common Errors.


One or more specified values aren't valid. For example, a required value might be missing, a numeric value might be outside the allowed range, or a string value might exceed length constraints.

HTTP Status Code: 400


No namespace exists with the specified ID.

HTTP Status Code: 400


The operation can't be completed because you've reached the quota for the number of requests. For more information, see Amazon Cloud Map API request throttling quota in the Amazon Cloud Map Developer Guide.

HTTP Status Code: 400


No service exists with the specified ID.

HTTP Status Code: 400


DiscoverInstancesRevision Example

This example illustrates one usage of DiscoverInstancesRevision.

Sample Request

POST / HTTP/1.1 x-amz-date:20230607T233508Z authorization: AWS4-HMAC-SHA256 Credential=AKIAIOSFODNN7EXAMPLE/20230607/us-west-2/servicediscovery/aws4_request, SignedHeaders=content-length;content-type;host;user-agent;x-amz-date;x-amz-target, Signature=[calculated-signature] x-amz-target:Route53AutoNaming_v20170314.DiscoverInstancesRevision content-type:application/x-amz-json-1.1 content-length:[number of characters in the JSON string] { "NamespaceName": "", "ServiceName": "example-dns-pub-service" }

Sample Response

HTTP/1.1 200 Content-Length: [number of characters in the JSON string] Content-Type: application/x-amz-json-1.1 { "InstancesRevision": 1001 }

See Also

For more information about using this API in one of the language-specific Amazon SDKs, see the following: