Important points about SOAP

The following are some important points about SOAP:

• Envelope in every SOAP message has the root position and that is mandatory for all SOAP messages.
• Exactly one body element should be present inside one SOAP envelope.
• The Header element is an optional element. However, if that is present, then there should be only one Header element.
• The Header must appear as the first child of the envelope, before the body element.
• The ENV namespace prefix and the Envelope element are used in order to build one SOAP envelope. (Refer to the following example.)
• The encodingStyle attribute defines the data types used in the document. This gives a generalization of the data types that appear in the message. If this attribute appears on any SOAP element, it will apply the encoding rules to the element's contents and all child elements.

The following is an example of a v1.2-compliant SOAP message:

<?xml version = "1.0"?>
<SOAP-ENV:Envelope 
 xmlns:SOAP-ENV = "http://www.w3.org/2001/12/soap-envelope" 
 SOAP-ENV:encodingStyle = "http://www.w3.org/2001/12/soap-encoding">
 ...
 SOAP Message information goes here
 ...
</SOAP-ENV:Envelope>