Error Handling In Web Service
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XML Web Services (JAX-WS). This chapter includes the following sections: Overview of Exception Handling Using SOAP Faults Contents of the SOAP Fault Element Using Modeled Faults Using Unmodeled Faults Customizing the Exception Handling Process Disabling the Stack java web service error handling Trace from the SOAP Fault Other Exceptions Overview of Exception Handling Using SOAP Faults When web service error handling c# a Web service request is being processed, if an error is encountered, the nature of the error needs to be communicated to web service error handling net the client, or sender of the request. Because clients can be written on a variety of platforms using different languages, there must exist a standard, platform-independent mechanism for communicating the error. The SOAP specification (available at web service exception handling http://www.w3.org/TR/soap/) defines a standard, platform-independent way of describing the error within the SOAP message using a SOAP fault. In general, a SOAP fault is analogous to an application exception. SOAP faults are generated by receivers to report business logic errors or unexpected conditions. In JAX-WS, Java exceptions (java.lang.Exception) that are thrown by your Java Web service are mapped to a SOAP fault and returned to the client to communicate the reason for
Web Service Error Handling Best Practices
failure. SOAP faults can be one of the following types: Modeled—Maps to an exception that is thrown explicitly from the business logic of the Java code and mapped to wsdl:fault definitions in the WSDL file, when the Web service is deployed. In this case, the SOAP faults are predefined. Unmodeled—Maps to an exception (for example, java.lang.RuntimeException) that is generated at run-time when no business logic fault is defined in the WSDL. In this case, Java exceptions are represented as generic SOAP fault exceptions, javax.xml.ws.soap.SOAPFaultException. The faults are returned to the sender only if request/response messaging is in use. If a Web service operation is configured as one-way, the SOAP fault is not returned to the sender, but stored for further processing. As illustrated in Figure 16-1, JAX-WS handles SOAP fault processing during SOAP protocol binding. The SOAP binding maps exceptions to SOAP fault messages. Figure 16-1 How SOAP Faults Are Processed Description of "Figure 16-1 How SOAP Faults Are Processed" Contents of the SOAP Fault Element The SOAP
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Soap Error Handling
Documentation APIs and reference Dev centers Retired content Samples We’re sorry. The error handling in restful web services content you requested has been removed. You’ll be auto redirected in 1 second. .NET Framework 4 .NET Framework wsdl error handling Advanced Development XML Web Services Created Using ASP.NET and XML Web Service Clients XML Web Services Created Using ASP.NET and XML Web Service Clients Handling and Throwing Exceptions in https://docs.oracle.com/cd/E24329_01/web.1211/e24965/faults.htm XML Web Services Handling and Throwing Exceptions in XML Web Services Handling and Throwing Exceptions in XML Web Services XML Web Services Overview XML Web Services Using ASP.NET Building XML Web Service Clients Handling and Throwing Exceptions in XML Web Services How to: Throw Exceptions from a Web Service Created Using ASP.NET How to: Handle Exceptions Thrown by https://msdn.microsoft.com/en-us/library/ds492xtk(v=vs.100).aspx a Web Service Method Using SOAP Headers Customizing SOAP Message Formatting SOAP Message Modification Using SOAP Extensions Walkthrough: Customizing the Generation of Service Descriptions and Proxy Classes How to: Customize the Generation of Service Descriptions and Proxy Classes Data Types Supported by XML Web Services Created Using ASP.NET Attributes for XML Web Services Created Using ASP.NET and XML Web Service Clients XML Web Services and Apartment-Threaded COM Components Web Services Settings Schema XML Web Services Directives XML Schema Binding Support XML Web Services Tools Enabling Tracing in ASP.NET Web Services TOC Collapse the table of content Expand the table of content This documentation is archived and is not being maintained. This documentation is archived and is not being maintained. This documentation is archived and is not being maintained. Handling and Throwing Exceptions in XML Web Services Visual Studio 2010 Other Versions .NET Framework 2.0 .NET Framework 1.1 This topic is specific to a legacy technology. XML Web services and XML Web service clients should now be created using Windows Communication Foundation . Exceptions
commonly used to refer to the transmission of XML over HTTP, and the identification of XML resources via URIs. According to REST, HTTP, XML and URIs provide all the infrastructure for building robust web services, and most developers can http://archive.oreilly.com/pub/post/restful_error_handling.html therefore safely skip over the pain of learning SOAP and WSDL. If you are new to REST, check out Paul Prescod's excellent REST articles on xml.com. A major element of web services is planning for when things go wrong, and propagating error messages back to client applications. However, unlike SOAP, REST-based web services do not have a well-defined convention for returning error messages. In fact, after surveying a number of REST-based error handling web services in the wild, there appear to be four different alternatives for handling errors. Below, I outline the four alternatives, and then provide my opinion on which option or combination of options is best. Option 1: Stick to HTTP Error Codes In this scenario, the web service propagates error messages via standard HTTP Error Codes. For example, assume we have the following URL: http://www.example.com/xml/book?id=1234&dev_token=ABCD1234 This service expects a single parameter: id web service error indicating a book ID. The service extracts the id parameter, does a database look-up and returns an XML representation of the specified book. If the URL specifies an invalid or obsolete id parameter, the service returns an HTTP 404 Not Found Error Code. Option 2: Return an Empty Set In this scenario, the web service always returns back an XML document which can have 0 or more subelements. If some error occurs, an XML document with zero elements is returned. The O'Reilly Meerkat news service currently uses this approach. For example, the following URL connects to Meerkat and requests all Linux related articles from the past two days, and formats the results in RSS 0.91: http://www.oreillynet.com/meerkat/?c=cat10&t=2DAY&_fl=xml Now, try specifying an invalid category. For example, set c =ten, like this: http://www.oreillynet.com/meerkat/?c=ten&t=2DAY&_fl=rss In this case, Meerkat returns an RSS document with zero item elements. This indicates that there are no matching results, but it does not indicate whether this is a valid category ID which contains no news items, or an invalid category ID. Option 3: Use Extended HTTP Headers In this scenario, the web service always returns an HTTP 200 OK Status Code, but specifies an application specific error code within a separate HTTP Header. The Distributed Annotation System (DAS) currently uses this alternative