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E-MapReduce:ListComponents

Last Updated:Sep 08, 2025

Retrieves a list of components.

Debugging

You can run this interface directly in OpenAPI Explorer, saving you the trouble of calculating signatures. After running successfully, OpenAPI Explorer can automatically generate SDK code samples.

Authorization information

The following table shows the authorization information corresponding to the API. The authorization information can be used in the Action policy element to grant a RAM user or RAM role the permissions to call this API operation. Description:

  • Operation: the value that you can use in the Action element to specify the operation on a resource.
  • Access level: the access level of each operation. The levels are read, write, and list.
  • Resource type: the type of the resource on which you can authorize the RAM user or the RAM role to perform the operation. Take note of the following items:
    • For mandatory resource types, indicate with a prefix of * .
    • If the permissions cannot be granted at the resource level, All Resources is used in the Resource type column of the operation.
  • Condition Key: the condition key that is defined by the cloud service.
  • Associated operation: other operations that the RAM user or the RAM role must have permissions to perform to complete the operation. To complete the operation, the RAM user or the RAM role must have the permissions to perform the associated operations.
OperationAccess levelResource typeCondition keyAssociated operation
emr:ListComponentslist
*All Resources
*
    none
none

Request parameters

ParameterTypeRequiredDescriptionExample
RegionIdstringYes

The region ID. You can call the ListRegions view.

cn-hangzhou
ClusterIdstringYes

The cluster ID.

C-8CFEBCCFFEF5****
NextTokenstringNo

The pagination token that is used in the next request to retrieve a new page of results. If you leave this parameter empty, the query starts from the beginning.

""
MaxResultsintegerNo

The number of entries to return on each page.

10
ApplicationNamesarrayNo

The application name.

StringstringNo

The application name.

KNOX
ComponentNamesarrayNo

The list of component names.

StringstringNo

The component name.

KNOX
ComponentStatesarrayNo

The list of component status.

StringstringNo

The status of the component.

INSTALLED

Response parameters

ParameterTypeDescriptionExample
object

Schema of Response

Componentsarray<object>

The list of component information.

Componentobject

The component information.

ComponentNamestring

The component name.

KNOX
ApplicationNamestring

The application name.

KNOX
Replicainteger

The total number of instances on which the component is installed.

1
Namespacestring

The reserved field.

“”
Attributesarray

The list of attributes.

AttributeAttribute

The name of the attribute.

RequestIdstring

The request ID.

FFAC608A-5DC3-174F-93C6-9F88CA6D5875
NextTokenstring

A pagination token. It can be used in the next request to retrieve a new page of results.

DD6B1B2A-5837-5237-ABE4-FF0C89568980
MaxResultsinteger

The maximum number of entries returned.

20
TotalCountinteger

The total number of entries returned.

200

Examples

Sample success responses

JSONformat

{
  "Components": [
    {
      "ComponentName": "KNOX",
      "ApplicationName": "KNOX",
      "Replica": 1,
      "Namespace": "“”",
      "Attributes": [
        {
          "Key": "currentYarnRangerPluginState",
          "Value": true
        }
      ]
    }
  ],
  "RequestId": "FFAC608A-5DC3-174F-93C6-9F88CA6D5875",
  "NextToken": "DD6B1B2A-5837-5237-ABE4-FF0C89568980",
  "MaxResults": 20,
  "TotalCount": 200
}

Error codes

HTTP status codeError codeError message
400ConflictParametersParameters that must not be used together. %s
400IncompleteSignatureThe request signature is invalid.
400InvalidActionThe action %s requested is invalid.
400InvalidParameterThe specified parameter %s is not valid.
400InvalidParameterValueThe input parameter %s is invalid or out of range.
400MissingActionThe action %s requested is missing.
400MissingParameterThe input parameter %s that is mandatory for processing this request is not supplied.
400NotAuthorizedYou do not have permission to perform this action. %s
400ThrottlingExceptionThe request was denied due to request throttling. %s
404ResourceNotFoundThe resource not found by %s.
500InternalErrorThe request processing has failed due to some unknown error, exception or failure.
503ServiceFailureThe request has failed due to a temporary failure of %s service.
503ServiceUnavailableThe request has failed due to a temporary failure of the server.

For a list of error codes, visit the Service error codes.