Dell PowerStore 9000T EMC PowerStore REST API Developers Guide - Page 25

You can use nested notation syntax (

<reference_attribute_name>(<attr1?,<attr2>...)

) in a select expression to return

the values of attributes from related resource types. A related resource type is a resource type that is either referred to explicitly in the

definition of the target resource type or embedded in the target resource type.

Considerations

The following considerations apply to using the select parameter:

•

If a select request is made for an attribute that is not defined on the resource type, the server returns a

400 Bad Request

error.

•

If an attribute has a valid, empty string value, the server returns the value as

<attribute>:""

.

•

Although a response normally contains only the requested attributes, this is not guaranteed. You should therefore be prepared to

ignore unrequested properties.

Retrieving the name and create_time for a local_user

The following request retrieves values for the name and create_time attributes in the local_user resource collection:

Headers

Accept: application/json

Authorization: <auth_cookie>

Request

GET https://1.2.3.4/api/rest/local_user?select=name,role_id

Response

body

[

{

"name": "admin",

"role_id": "1"

},

{

"name": "stadmin",

"role_id": "2"

},

{

"name": "vmadmin",

"role_id": "4"

}

]

Filtering response data

Use one or more filter expressions in a request parameter to specify matching criteria for a list of resources returned by a collection query.

A filter expression works like an SQL WHERE clause. You specify a filter expression composed of boolean predicates, and the expression is

applied against the attribute values of the requested resource type. Only those instances that cause the filter expression to evaluate to

true are returned in the query response. The system ANDs together multiple filter expressions.

Filter expressions use operators such as gt, gte, lt, and lte. The interpretation of these operators is type-dependent. For example, gt used

with datetime attributes means the date value to the right of gt must be more recent than the date value to the left of gt.

Filtering is case insensitive for any property called name.

Using a filter expression can save bandwidth, because the server removes extra data before returning data to the client. However a filter

expression does not reduce the amount of work the server performs to answer the request.

NOTE:

Complex requests can be slow or can fail.

Syntax

As the first parameter on the request URI:

?<attribute_name>=<filter_expr>

As a subsequent parameter on the request URI:

&<attribute_name>=<filter_expr>

where

<filter_expr>

is defined by the following syntax :

Querying a resource

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