Dave Angulo - SOAP

SOAP is a lightweight data transmission protocol. It has no fault-tolerance. It has no resource discovery. It does not serialize the objects being marshalled across the connection; however, there are other protocols used on top of SOAP which do handle the serialization for you.

SOAP is based on XML as the data marshalling format. This is beneficial as it is understandable to both machines and humans. SOAP does not specify a transmission protocol, but HTTP is mainly used.

Here are some XML resources:

• A good all-round site of software from Apache
• W3.org page containing links to tutorials, specifications, software, etc.
• A FAQ about XML
• Here are resources for XML Schema (Schema is important for SOAP):
  • XML Schema Primer Part 0.
  • XML Schema Part 1: Structures
  • XML Schema Part 2: Datatypes
• XML Namespaces are important too
• A page of XML links
• Here are resources for XML DOM:
  • An extremely short tutorial on DOM
  • A DOM tutorial in JavaScript
    This includes a useful XML editing and display page
  • Java.Sun's tutorial on XML (section on DOM)
• Here are tutorials that go over all aspects of XML:
  • An overview of XML many topics. Note that this is not usefule for advanced technical information.
  • Java.Sun's tutorial on XML which is perhaps the tutorial.
• A news site (like slashdot) for XML developers
• A list of sites that deliver XML content

Here are some SOAP speficiations:

• Dave Winer´s A Busy Developer´s Guide to Soap is a good overview.
• Young Person´s Guide to SOAP is a good overview
• MSDN Web Workshop has a good introduction
  • MSDN Web Services is a page with a lot of links, but the text doesn't display well (even in IE!)

Here are some SOAP implementations in C++

• We had been using the Idoox implementation. This link is the Java API (similar to the C++ API). We abandoned their implementation, though, because they decided to stop supporting the C++ implementation. I understand that they have started supporting it again (so the next paragraph might be out of date), but I have not yet had a chance to check out their new implementation.
  Note that the Idoox pacakge uses SCL which has been supplanted by WSDL. There doesn't appear to be any documentation pages for SCL, but that is OK as the Idoox package has a Java to SC L translator and then an SCL to C++ Stubs and C++ Skeletons package. Therefore, y ou don't really ever have to even look at the SCL.
• The Extreme! Computing people at Indiana University have a C++ implementation. They call it SoapRMI.
• EasySOAP++ is another C++ implementation from SCITEGIC.
• Simple Soap Library from Scott Seely
• White Mesa
• SQLData

Here are some other topics related to SOAP:

• Security in SOAP
• W3C Soap Security Extensions - Digital Signatures
• Soap Security Extensions including Encryption, Digital Signatures, and Authorization.