registerInstance method

Future<RegisterInstanceResponse> registerInstance({
  1. required Map<String, String> attributes,
  2. required String instanceId,
  3. required String serviceId,
  4. String? creatorRequestId,
})

Creates or updates one or more records and, optionally, creates a health check based on the settings in a specified service. When you submit a RegisterInstance request, the following occurs:

  • For each DNS record that you define in the service that's specified by ServiceId, a record is created or updated in the hosted zone that's associated with the corresponding namespace.
  • If the service includes HealthCheckConfig, a health check is created based on the settings in the health check configuration.
  • The health check, if any, is associated with each of the new or updated records.
For more information, see CreateService.

When Cloud Map receives a DNS query for the specified DNS name, it returns the applicable value:

  • If the health check is healthy: returns all the records
  • If the health check is unhealthy: returns the applicable value for the last healthy instance
  • If you didn't specify a health check configuration: returns all the records
For the current quota on the number of instances that you can register using the same namespace and using the same service, see Cloud Map quotas in the Cloud Map Developer Guide.

May throw DuplicateRequest. May throw InvalidInput. May throw ResourceInUse. May throw ResourceLimitExceeded. May throw ServiceNotFound.

Parameter attributes : A string map that contains the following information for the service that you specify in ServiceId:

  • The attributes that apply to the records that are defined in the service.
  • For each attribute, the applicable value.
The following are the supported attribute keys.
AWS_ALIAS_DNS_NAME
If you want Cloud Map to create an Amazon Route 53 alias record that routes traffic to an Elastic Load Balancing load balancer, specify the DNS name that's associated with the load balancer. For information about how to get the DNS name, see "DNSName" in the topic AliasTarget in the Route 53 API Reference.

Note the following:

  • The configuration for the service that's specified by ServiceId must include settings for an A record, an AAAA record, or both.
  • In the service that's specified by ServiceId, the value of RoutingPolicy must be WEIGHTED.
  • If the service that's specified by ServiceId includes HealthCheckConfig settings, Cloud Map will create the Route 53 health check, but it doesn't associate the health check with the alias record.
  • Cloud Map currently doesn't support creating alias records that route traffic to Amazon Web Services resources other than Elastic Load Balancing load balancers.
  • If you specify a value for AWS_ALIAS_DNS_NAME, don't specify values for any of the AWS_INSTANCE attributes.
  • The AWS_ALIAS_DNS_NAME is not supported in the GovCloud (US) Regions.
AWS_EC2_INSTANCE_ID
HTTP namespaces only. The Amazon EC2 instance ID for the instance. If the AWS_EC2_INSTANCE_ID attribute is specified, then the only other attribute that can be specified is AWS_INIT_HEALTH_STATUS. When the AWS_EC2_INSTANCE_ID attribute is specified, then the AWS_INSTANCE_IPV4 attribute will be filled out with the primary private IPv4 address.
AWS_INIT_HEALTH_STATUS
If the service configuration includes HealthCheckCustomConfig, you can optionally use AWS_INIT_HEALTH_STATUS to specify the initial status of the custom health check, HEALTHY or UNHEALTHY. If you don't specify a value for AWS_INIT_HEALTH_STATUS, the initial status is HEALTHY.
AWS_INSTANCE_CNAME
If the service configuration includes a CNAME record, the domain name that you want Route 53 to return in response to DNS queries (for example, example.com).

This value is required if the service specified by ServiceId includes settings for an CNAME record.

AWS_INSTANCE_IPV4
If the service configuration includes an A record, the IPv4 address that you want Route 53 to return in response to DNS queries (for example, 192.0.2.44).

This value is required if the service specified by ServiceId includes settings for an A record. If the service includes settings for an SRV record, you must specify a value for AWS_INSTANCE_IPV4, AWS_INSTANCE_IPV6, or both.

AWS_INSTANCE_IPV6
If the service configuration includes an AAAA record, the IPv6 address that you want Route 53 to return in response to DNS queries (for example, 2001:0db8:85a3:0000:0000:abcd:0001:2345).

This value is required if the service specified by ServiceId includes settings for an AAAA record. If the service includes settings for an SRV record, you must specify a value for AWS_INSTANCE_IPV4, AWS_INSTANCE_IPV6, or both.

AWS_INSTANCE_PORT
If the service includes an SRV record, the value that you want Route 53 to return for the port.

If the service includes HealthCheckConfig, the port on the endpoint that you want Route 53 to send requests to.

This value is required if you specified settings for an SRV record or a Route 53 health check when you created the service.

Custom attributes
You can add up to 30 custom attributes. For each key-value pair, the maximum length of the attribute name is 255 characters, and the maximum length of the attribute value is 1,024 characters. The total size of all provided attributes (sum of all keys and values) must not exceed 5,000 characters.

Parameter instanceId : An identifier that you want to associate with the instance. Note the following:

  • If the service that's specified by ServiceId includes settings for an SRV record, the value of InstanceId is automatically included as part of the value for the SRV record. For more information, see DnsRecord > Type.
  • You can use this value to update an existing instance.
  • To register a new instance, you must specify a value that's unique among instances that you register by using the same service.
  • If you specify an existing InstanceId and ServiceId, Cloud Map updates the existing DNS records, if any. If there's also an existing health check, Cloud Map deletes the old health check and creates a new one.

Parameter serviceId : The ID or Amazon Resource Name (ARN) of the service that you want to use for settings for the instance. For services created in a shared namespace, specify the service ARN. For more information about shared namespaces, see Cross-account Cloud Map namespace sharing in the Cloud Map Developer Guide.

Parameter creatorRequestId : A unique string that identifies the request and that allows failed RegisterInstance requests to be retried without the risk of executing the operation twice. You must use a unique CreatorRequestId string every time you submit a RegisterInstance request if you're registering additional instances for the same namespace and service. CreatorRequestId can be any unique string (for example, a date/time stamp).

Implementation

Future<RegisterInstanceResponse> registerInstance({
  required Map<String, String> attributes,
  required String instanceId,
  required String serviceId,
  String? creatorRequestId,
}) async {
  final headers = <String, String>{
    'Content-Type': 'application/x-amz-json-1.1',
    'X-Amz-Target': 'Route53AutoNaming_v20170314.RegisterInstance'
  };
  final jsonResponse = await _protocol.send(
    method: 'POST',
    requestUri: '/',
    exceptionFnMap: _exceptionFns,
    // TODO queryParams
    headers: headers,
    payload: {
      'Attributes': attributes,
      'InstanceId': instanceId,
      'ServiceId': serviceId,
      'CreatorRequestId': creatorRequestId ?? _s.generateIdempotencyToken(),
    },
  );

  return RegisterInstanceResponse.fromJson(jsonResponse.body);
}