Doc/lit doesn't define type mappings, but it definitively specifies the structure of the message via XML Schema. Because the two applications know in advance exactly what the message structure is, the details of how the SOAP message processor maps the XML Schema to language types doesn't matter to the other application. When using rpc/encoded, the two applications have not agreed to a specific message structure. The SOAP message processor generates the SOAP message structure based on it's specific interpretation of SOAP Section 5, and there's no definitive schema of the message. The interoperability issues arise when two different SOAP message procesors interpret SOAP Section 5 slightly differently.
Anne ----- Original Message ----- From: "Scott Nichol" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, June 18, 2003 3:18 PM Subject: Re: design question > In what way does doc/lit define language type mappings? I've never > really understood why doc/lit is better than rpc/encoded. If you > have no WSDL, you have problems with complex types either way. If > you do have WSDL, you have XML type information either way, and I > don't see why you would bind any differently. I've seen the merits > of doc/lit v. rpc/encoded discussed in various places, but never > understood any type mapping advantage. > > On 18 Jun 2003 at 13:20, Anne Thomas Manes wrote: > > > From my perspective you should always use Doc/literal. SOAP Encoding has been the source of many interoperability issues, because the mechanism of mapping language types isn't defined concretely by SOAP Section 5. Hence you should always use literal encoding. And many implementations don't > support RPC/Literal. > > > > I'm not sure why you found it necessary to use RPC/encoded in order to get the SOAP deserializer to return a string. You should be able to make that happen using Doc/Literal, if that's what you want -- the serialization requirements should be specified in the deployment descriptor. > > > > I don't think that any SOAP engines do automatic schema validation (there's sufficient overhead associated with the process that you wouldn't want to do it by default). But many of the commercial implementations provide typed interceptors that make it simple to request validation (sometimes > just by declaring a deployment option). > > > > Anne > > ----- Original Message ----- > > From: Vishal Shah > > To: [EMAIL PROTECTED] > > Sent: Wednesday, June 18, 2003 10:58 AM > > Subject: Re: design question > > > > > > Thanks Anne for elucidating. I'm stuck with the legacy system and infrastructure that supports it.. I need to find a clumsy way to get around to make things work.. > > > > I don't concur with you on thing you mentioned below in the first paragraph. If you factor interoperability & infrastructure issues in, your design would be definitely affected accordingly. If your service is going to be consumed by a VB6 client or .net client (or any non-java consumer), > RPC/literal is not the right solution. In that case, the service should be designed to use Doc/literal. Also, RPC/Encoding is not always the right design for interopetability reasons. I had my original service return a DOM element and due to interoperability reasons, I turned in to RPC/Encoding > type that returns a String containing XML representation. > > > > Are there any "smart SOAP runtime" that provides validation using schema ? > > > > Anne Thomas Manes <[EMAIL PROTECTED]> wrote: > > Vishal, > > > > A SOAP runtime system should provide a layer of abstraction between your message format and the application that implements the service. Hence the format of the message (Doc/literal vs RPC/encoded) shouldn't really impact the design of your service. The SOAP runtime system should be able to > marshal and unmarshal the messages, map XML to Java, dispatch the appropriate application, and transform exceptions into SOAP fault messages for you -- all based on the WSDL description and deployment descriptor -- regardless of whether you use RPC or document style messages. Your application > shouldn't need to process XML unless you choose to receive the message as an XML document. > > > > You should not assume that the SOAP runtime will validate the document. If you want it to perform validation before processing, you would need to specify a validation interceptor in your deployment descriptor (to call a handler in your handler chain). You should assume that the SOAP runtime > will parse the document and deserialize it into Java objects. If you are using RPC/encoded, then it does the mapping based on the SOAP Section 5 data model. If you are using Document/Literal, then it does the mapping based on the XML Schema message description. > > > > When writing a service, you should do what you would normally do in any Java application -- throw an exception. The SOAP runtime system should catch the exception and transform it into the appropriate SOAP fault message. The client SOAP runtime system should be able to interpret the SOAP > fault, and assuming it's a Java system, rethrow the exception for the client. > > > > Now, of course, these best practices don't necessarily apply to Web services written using Apache SOAP. You must realise that Apache SOAP is a very old SOAP implementation that doesn't support WSDL, is very RPC/encoded-centric, and doesn't support doc/literal according to the standard. > > > > Unless you have legacy applications based on Apache SOAP, I recommend that you start using Apache Axis (http://ws.apache.org/axis), or any of the 20 or so commercial implementations that fully support SOAP 1.1, WSDL 1.1, JAX-RPC, and the WS-I Basic Profile. > > > > Best regards, > > Anne > > > > ----- Original Message ----- > > From: Vishal Shah > > To: [EMAIL PROTECTED] > > Sent: Tuesday, June 17, 2003 10:59 AM > > Subject: design question > > > > > > Hi, > > > > I've a couple of design questions...I've a Doc/literal style service.. > > > > What's the best way to handle any abnormal conditions and errors ?Should the service throw an exception or should it create a "error" element in a response document ? > > > > Is it safe to assume that in Doc/literal style, a doc gets parsed and validated using a schema ? If not, is the service responsible for validating (coarse-grained validation) the document ? Pl advise... > > > > Thanks > > VS > > > > > > > > -------------------------------------------------------------------------- > > Do you Yahoo!? > > SBC Yahoo! DSL - Now only $29.95 per month! > > > > > > -------------------------------------------------------------------------- ---- > > Do you Yahoo!? > > SBC Yahoo! DSL - Now only $29.95 per month! > > > > > Scott Nichol > > Do not reply directly to this e-mail address, > as it is filtered to only receive e-mail from > specific mailing lists. > >
