[ aws . servicediscovery ]

list-services

Description

Lists summary information for all the services that are associated with one or more specified namespaces.

See also: AWS API Documentation

See ‘aws help’ for descriptions of global parameters.

list-services is a paginated operation. Multiple API calls may be issued in order to retrieve the entire data set of results. You can disable pagination by providing the --no-paginate argument. When using --output text and the --query argument on a paginated response, the --query argument must extract data from the results of the following query expressions: Services

Synopsis

  list-services
[--filters <value>]
[--cli-input-json | --cli-input-yaml]
[--starting-token <value>]
[--page-size <value>]
[--max-items <value>]
[--generate-cli-skeleton <value>]

Options

--filters (list)

A complex type that contains specifications for the namespaces that you want to list services for.

If you specify more than one filter, an operation must match all filters to be returned by ListServices .

(structure)

A complex type that lets you specify the namespaces that you want to list services for.

Name -> (string)

Specify NAMESPACE_ID .

Values -> (list)

The values that are applicable to the value that you specify for Condition to filter the list of services.

(string)

Condition -> (string)

The operator that you want to use to determine whether a service is returned by ListServices . Valid values for Condition include the following:

  • EQ : When you specify EQ , specify one namespace ID for Values . EQ is the default condition and can be omitted.

  • IN : When you specify IN , specify a list of the IDs for the namespaces that you want ListServices to return a list of services for.

  • BETWEEN : Not applicable.

Shorthand Syntax:

Name=string,Values=string,string,Condition=string ...

JSON Syntax:

[
  {
    "Name": "NAMESPACE_ID",
    "Values": ["string", ...],
    "Condition": "EQ"|"IN"|"BETWEEN"
  }
  ...
]

--cli-input-json | --cli-input-yaml (string) Reads arguments from the JSON string provided. The JSON string follows the format provided by --generate-cli-skeleton. If other arguments are provided on the command line, those values will override the JSON-provided values. It is not possible to pass arbitrary binary values using a JSON-provided value as the string will be taken literally. This may not be specified along with --cli-input-yaml.

--starting-token (string)

A token to specify where to start paginating. This is the NextToken from a previously truncated response.

For usage examples, see Pagination in the AWS Command Line Interface User Guide .

--page-size (integer)

The size of each page to get in the AWS service call. This does not affect the number of items returned in the command’s output. Setting a smaller page size results in more calls to the AWS service, retrieving fewer items in each call. This can help prevent the AWS service calls from timing out.

For usage examples, see Pagination in the AWS Command Line Interface User Guide .

--max-items (integer)

The total number of items to return in the command’s output. If the total number of items available is more than the value specified, a NextToken is provided in the command’s output. To resume pagination, provide the NextToken value in the starting-token argument of a subsequent command. Do not use the NextToken response element directly outside of the AWS CLI.

For usage examples, see Pagination in the AWS Command Line Interface User Guide .

--generate-cli-skeleton (string) Prints a JSON skeleton to standard output without sending an API request. If provided with no value or the value input, prints a sample input JSON that can be used as an argument for --cli-input-json. Similarly, if provided yaml-input it will print a sample input YAML that can be used with --cli-input-yaml. If provided with the value output, it validates the command inputs and returns a sample output JSON for that command.

See ‘aws help’ for descriptions of global parameters.

Examples

To list services

The following list-services example lists services.

aws servicediscovery list-services

Output:

{
    "Services": [
        {
            "Id": "srv-p5zdwlg5uvvzjita",
            "Arn": "arn:aws:servicediscovery:us-west-2:123456789012:service/srv-p5zdwlg5uvvzjita",
            "Name": "myservice",
            "DnsConfig": {
                "RoutingPolicy": "MULTIVALUE",
                "DnsRecords": [
                    {
                        "Type": "A",
                        "TTL": 60
                    }
                ]
            },
            "CreateDate": 1587081768.334
        }
    ]
}

For more information, see Viewing a list of services in the AWS Cloud Map Developer Guide.

Output

Services -> (list)

An array that contains one ServiceSummary object for each service that matches the specified filter criteria.

(structure)

A complex type that contains information about a specified service.

Id -> (string)

The ID that AWS Cloud Map assigned to the service when you created it.

Arn -> (string)

The Amazon Resource Name (ARN) that AWS Cloud Map assigns to the service when you create it.

Name -> (string)

The name of the service.

Type -> (string)

Describes the systems that can be used to discover the service instances.

DNS_HTTP

The service instances can be discovered using either DNS queries or the DiscoverInstances API operation.

HTTP

The service instances can only be discovered using the DiscoverInstances API operation.

DNS

Reserved.

Description -> (string)

The description that you specify when you create the service.

InstanceCount -> (integer)

The number of instances that are currently associated with the service. Instances that were previously associated with the service but that have been deleted are not included in the count. The count might not reflect pending registrations and deregistrations.

DnsConfig -> (structure)

A complex type that contains information about the Amazon Route 53 DNS records that you want AWS Cloud Map to create when you register an instance.

NamespaceId -> (string)

The ID of the namespace to use for DNS configuration.

RoutingPolicy -> (string)

The routing policy that you want to apply to all Route 53 DNS records that AWS Cloud Map creates when you register an instance and specify this service.

Note

If you want to use this service to register instances that create alias records, specify WEIGHTED for the routing policy.

You can specify the following values:

MULTIVALUE

If you define a health check for the service and the health check is healthy, Route 53 returns the applicable value for up to eight instances.

For example, suppose the service includes configurations for one A record and a health check, and you use the service to register 10 instances. Route 53 responds to DNS queries with IP addresses for up to eight healthy instances. If fewer than eight instances are healthy, Route 53 responds to every DNS query with the IP addresses for all of the healthy instances.

If you don’t define a health check for the service, Route 53 assumes that all instances are healthy and returns the values for up to eight instances.

For more information about the multivalue routing policy, see Multivalue Answer Routing in the Route 53 Developer Guide .

WEIGHTED

Route 53 returns the applicable value from one randomly selected instance from among the instances that you registered using the same service. Currently, all records have the same weight, so you can’t route more or less traffic to any instances.

For example, suppose the service includes configurations for one A record and a health check, and you use the service to register 10 instances. Route 53 responds to DNS queries with the IP address for one randomly selected instance from among the healthy instances. If no instances are healthy, Route 53 responds to DNS queries as if all of the instances were healthy.

If you don’t define a health check for the service, Route 53 assumes that all instances are healthy and returns the applicable value for one randomly selected instance.

For more information about the weighted routing policy, see Weighted Routing in the Route 53 Developer Guide .

DnsRecords -> (list)

An array that contains one DnsRecord object for each Route 53 DNS record that you want AWS Cloud Map to create when you register an instance.

(structure)

A complex type that contains information about the Route 53 DNS records that you want AWS Cloud Map to create when you register an instance.

Type -> (string)

The type of the resource, which indicates the type of value that Route 53 returns in response to DNS queries. You can specify values for Type in the following combinations:

  • A

  • AAAA

  • A and AAAA

  • SRV

  • CNAME

If you want AWS Cloud Map to create a Route 53 alias record when you register an instance, specify A or AAAA for Type .

You specify other settings, such as the IP address for A and AAAA records, when you register an instance. For more information, see RegisterInstance .

The following values are supported:

A ** **

Route 53 returns the IP address of the resource in IPv4 format, such as 192.0.2.44.

AAAA ** **

Route 53 returns the IP address of the resource in IPv6 format, such as 2001:0db8:85a3:0000:0000:abcd:0001:2345.

CNAME ** **

Route 53 returns the domain name of the resource, such as www.example.com. Note the following:

  • You specify the domain name that you want to route traffic to when you register an instance. For more information, see Attributes in the topic RegisterInstance .

  • You must specify WEIGHTED for the value of RoutingPolicy .

  • You can’t specify both CNAME for Type and settings for HealthCheckConfig . If you do, the request will fail with an InvalidInput error.

SRV

Route 53 returns the value for an SRV record. The value for an SRV record uses the following values:

priority weight port service-hostname

Note the following about the values:

  • The values of priority and weight are both set to 1 and can’t be changed.

  • The value of port comes from the value that you specify for the AWS_INSTANCE_PORT attribute when you submit a RegisterInstance request.

  • The value of service-hostname is a concatenation of the following values:

    • The value that you specify for InstanceId when you register an instance.

    • The name of the service.

    • The name of the namespace.

For example, if the value of InstanceId is test , the name of the service is backend , and the name of the namespace is example.com , the value of service-hostname is:

test.backend.example.com

If you specify settings for an SRV record, note the following:

  • If you specify values for AWS_INSTANCE_IPV4 , AWS_INSTANCE_IPV6 , or both in the RegisterInstance request, AWS Cloud Map automatically creates A and/or AAAA records that have the same name as the value of service-hostname in the SRV record. You can ignore these records.

  • If you’re using a system that requires a specific SRV format, such as HAProxy, see the Name element in the documentation about CreateService for information about how to specify the correct name format.

TTL -> (long)

The amount of time, in seconds, that you want DNS resolvers to cache the settings for this record.

Note

Alias records don’t include a TTL because Route 53 uses the TTL for the AWS resource that an alias record routes traffic to. If you include the AWS_ALIAS_DNS_NAME attribute when you submit a RegisterInstance request, the TTL value is ignored. Always specify a TTL for the service; you can use a service to register instances that create either alias or non-alias records.

HealthCheckConfig -> (structure)

Public DNS and HTTP namespaces only. A complex type that contains settings for an optional health check. If you specify settings for a health check, AWS Cloud Map associates the health check with the records that you specify in DnsConfig .

Warning

If you specify a health check configuration, you can specify either HealthCheckCustomConfig or HealthCheckConfig but not both.

Health checks are basic Route 53 health checks that monitor an AWS endpoint. For information about pricing for health checks, see Amazon Route 53 Pricing .

Note the following about configuring health checks.

** A and AAAA records**

If DnsConfig includes configurations for both A and AAAA records, AWS Cloud Map creates a health check that uses the IPv4 address to check the health of the resource. If the endpoint that is specified by the IPv4 address is unhealthy, Route 53 considers both the A and AAAA records to be unhealthy.

** CNAME records**

You can’t specify settings for HealthCheckConfig when the DNSConfig includes CNAME for the value of Type . If you do, the CreateService request will fail with an InvalidInput error.

Request interval

A Route 53 health checker in each health-checking region sends a health check request to an endpoint every 30 seconds. On average, your endpoint receives a health check request about every two seconds. However, health checkers don’t coordinate with one another, so you’ll sometimes see several requests per second followed by a few seconds with no health checks at all.

Health checking regions

Health checkers perform checks from all Route 53 health-checking regions. For a list of the current regions, see Regions .

Alias records

When you register an instance, if you include the AWS_ALIAS_DNS_NAME attribute, AWS Cloud Map creates a Route 53 alias record. Note the following:

  • Route 53 automatically sets EvaluateTargetHealth to true for alias records. When EvaluateTargetHealth is true, the alias record inherits the health of the referenced AWS resource. such as an ELB load balancer. For more information, see EvaluateTargetHealth .

  • If you include HealthCheckConfig and then use the service to register an instance that creates an alias record, Route 53 doesn’t create the health check.

Charges for health checks

Health checks are basic Route 53 health checks that monitor an AWS endpoint. For information about pricing for health checks, see Amazon Route 53 Pricing .

Type -> (string)

The type of health check that you want to create, which indicates how Route 53 determines whether an endpoint is healthy.

Warning

You can’t change the value of Type after you create a health check.

You can create the following types of health checks:

  • HTTP : Route 53 tries to establish a TCP connection. If successful, Route 53 submits an HTTP request and waits for an HTTP status code of 200 or greater and less than 400.

  • HTTPS : Route 53 tries to establish a TCP connection. If successful, Route 53 submits an HTTPS request and waits for an HTTP status code of 200 or greater and less than 400.

Warning

If you specify HTTPS for the value of Type , the endpoint must support TLS v1.0 or later.

  • TCP : Route 53 tries to establish a TCP connection. If you specify TCP for Type , don’t specify a value for ResourcePath .

For more information, see How Route 53 Determines Whether an Endpoint Is Healthy in the Route 53 Developer Guide .

ResourcePath -> (string)

The path that you want Route 53 to request when performing health checks. The path can be any value for which your endpoint will return an HTTP status code of 2xx or 3xx when the endpoint is healthy, such as the file /docs/route53-health-check.html . Route 53 automatically adds the DNS name for the service. If you don’t specify a value for ResourcePath , the default value is / .

If you specify TCP for Type , you must not specify a value for ResourcePath .

FailureThreshold -> (integer)

The number of consecutive health checks that an endpoint must pass or fail for Route 53 to change the current status of the endpoint from unhealthy to healthy or vice versa. For more information, see How Route 53 Determines Whether an Endpoint Is Healthy in the Route 53 Developer Guide .

HealthCheckCustomConfig -> (structure)

A complex type that contains information about an optional custom health check. A custom health check, which requires that you use a third-party health checker to evaluate the health of your resources, is useful in the following circumstances:

  • You can’t use a health check that is defined by HealthCheckConfig because the resource isn’t available over the internet. For example, you can use a custom health check when the instance is in an Amazon VPC. (To check the health of resources in a VPC, the health checker must also be in the VPC.)

  • You want to use a third-party health checker regardless of where your resources are.

Warning

If you specify a health check configuration, you can specify either HealthCheckCustomConfig or HealthCheckConfig but not both.

To change the status of a custom health check, submit an UpdateInstanceCustomHealthStatus request. AWS Cloud Map doesn’t monitor the status of the resource, it just keeps a record of the status specified in the most recent UpdateInstanceCustomHealthStatus request.

Here’s how custom health checks work:

  • You create a service and specify a value for FailureThreshold . The failure threshold indicates the number of 30-second intervals you want AWS Cloud Map to wait between the time that your application sends an UpdateInstanceCustomHealthStatus request and the time that AWS Cloud Map stops routing internet traffic to the corresponding resource.

  • You register an instance.

  • You configure a third-party health checker to monitor the resource that is associated with the new instance.

Note

AWS Cloud Map doesn’t check the health of the resource directly.

  • The third-party health-checker determines that the resource is unhealthy and notifies your application.

  • Your application submits an UpdateInstanceCustomHealthStatus request.

  • AWS Cloud Map waits for (FailureThreshold x 30) seconds.

  • If another UpdateInstanceCustomHealthStatus request doesn’t arrive during that time to change the status back to healthy, AWS Cloud Map stops routing traffic to the resource.

FailureThreshold -> (integer)

Warning

This parameter has been deprecated and is always set to 1. AWS Cloud Map waits for approximately 30 seconds after receiving an UpdateInstanceCustomHealthStatus request before changing the status of the service instance.

The number of 30-second intervals that you want AWS Cloud Map to wait after receiving an UpdateInstanceCustomHealthStatus request before it changes the health status of a service instance.

Sending a second or subsequent UpdateInstanceCustomHealthStatus request with the same value before 30 seconds has passed doesn’t accelerate the change. AWS Cloud Map still waits 30 seconds after the first request to make the change.

CreateDate -> (timestamp)

The date and time that the service was created.

NextToken -> (string)

If the response contains NextToken , submit another ListServices request to get the next group of results. Specify the value of NextToken from the previous response in the next request.

Note

AWS Cloud Map gets MaxResults services and then filters them based on the specified criteria. It’s possible that no services in the first MaxResults services matched the specified criteria but that subsequent groups of MaxResults services do contain services that match the criteria.