Web Services Translator

The Web Services translator, known by the type name ws, exposes stored procedures for calling web services backed by a Teiid WS resource adapter. The WS resource adapter may optionally be configured to point at a specific WSDL.  Results from this translator will commonly be used with the TEXTTABLE or XMLTABLE table functions to use CSV or XML formated data.

Execution Properties 

Setting the proper binding value on the translator is recommended as it removes the need for callers to pass an explicit value. If your service is actually uses SOAP11, but the binding used SOAP12 you will receive execution failures.

There are no ws importer settings, but it does provide metadata for dynamic VDBs.  If the connection is configured to point at a specific WSDL, the translator will import all SOAP operations under the specified service and port as procedures.

Usage

The WS translator exposes low level procedures for accessing web services. See also the twitter example in the kit.

Invoke Procedure

Invoke allows for multiple binding, or protocol modes, including HTTP, SOAP11, and SOAP12.

Procedure invoke(binding in STRING, action in STRING, request in XML, endpoint in STRING, stream in BOOLEAN) returns XML

The binding may be one of null (to use the default) HTTP, SOAP11, or SOAP12. Action with a SOAP binding indicates the SOAPAction value. Action with a HTTP binding indicates the HTTP method (GET, POST, etc.), which defaults to POST.

A null value for the binding or endpoint will use the default value. The default endpoint is specified in the WS resource adapter configuration. The endpoint URL may be absolute or relative. If it's relative then it will be combined with the default endpoint.

Since multiple parameters are not required to have values, it is often more clear to call the invoke procedure with named parameter syntax.

call invoke(binding=>'HTTP', action=>'GET')

The request XML should be a valid XML document or root element.

InvokeHTTP Procedure

invokeHttp can return the byte contents of an HTTP(S) call.

Procedure invokeHttp(action in STRING, request in OBJECT, endpoint in STRING, stream in BOOLEAN, contentType out STRING) returns BLOB

Action indicates the HTTP method (GET, POST, etc.), which defaults to POST.

A null value for endpoint will use the default value. The default endpoint is specified in the WS resource adapter configuration. The endpoint URL may be absolute or relative. If it's relative then it will be combined with the default endpoint.

Since multiple parameters are not required to have values, it is often more clear to call the invoke procedure with named parameter syntax.

call invokeHttp(action=>'GET')

The request can be one of SQLXML, STRING, BLOB, or CLOB. The request will be sent as the POST payload in byte form. For STRING/CLOB values this will default to the UTF-8 encoding. To control the byte encoding, see the to_bytes function.

Native queries Native queries or a direct query execution procedure is not supported on the Web Services Translator.

Streaming Considerations

If the stream parameter is set to true, then the resulting lob value may only be used a single time. If stream is null or false, then the engine may need to save a copy of the result for repeated use. Care must be used as some operations, such as casting or XMLPARSE may perform validation which results in the stream being consumed.

JCA Resource Adapter

The resource adapter for this translator provided through Web Service Data Source.