VMware VCLOUD API 1.0 - TECHNICAL NOTE, Руководство по программированию

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The vCloud API represents objects in a vCloud as XML documents in which object properties are encoded as
elements and attributes with typed values and an explicit object hierarchy defined by an XML schema. This
chapter provides reference information about how the vCloud API uses XML to represent vCloud objects.
This chapter includes the following topics:

“About Object Representations” on page 141

“Common Datatypes” on page 142

“Common Attributes” on page 143

“Common Elements” on page 146

“API Versioning” on page 147

“Extensibility” on page 148
About Object Representations
Client programs of RESTful Web services must be able to request object representations from the server, parse
the server’s responses to extract the information they contain, and compose requests that, in many cases, are
based on the information extracted from a response. Developers of such clients must understand the structure
of each representation that might be part of a request or response, as well as any requirements that the network
protocol (HTTP) places on client ‐ server interaction. In this guide, reference information on each object
representation includes the XML schema of the element that represents the object, the object type (encoded as
the MIME content type of the request or response), and a prototype of the object reference (a URL).
Schema
Each vCloud API object is defined in an XML schema document. Some objects are defined in their own schema
documents. Others are defined in the context of the larger schema in which they are used. Still others are
defined in a common schema document, from which other schemas inherit. This guide presents reference
information about XML schemas in tabular form, as shown in Table 8 ‐ 1 .
XML Representations in the
vCloud API
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Table 8-1. Schema Reference Table Columns
Name Min Max Type Description
Name of an element or
attribute contained.
Element names begin
with an uppercase
character. Attribute
names begin with a
lowercase character.
Minimum number of
this attribute or
element required by
the schema.
Maximum number of
this attribute or
element allowed by the
schema. A value of n
means that the
maximum number is
unlimited.
Type of the attribute or
element, either a
primitive XML
datatype or a complex
type defined by the
vCloud API.
Description of the
attribute or element