Building SOAP request from WSDL - web-services

Question

I need to execute a SOAP request to an external server. I have never worked with SOAP before, but I know the basics of REST.
I've been given this following WSDL file and this example query:
<Messages>
<Version Ds_Version="0.0">
<Message>
<Detail>
<Ds_MerchantCode>999008881</Ds_MerchantCode>
<Ds_Terminal>1</Ds_Terminal>
<Ds_Order>5799L</Ds_Order>
<Ds_TransactionType>3</Ds_TransactionType>
</Detail>
</Message>
</Version>
<Signature>UfECD0KD9Wwo1iqY6PYZoJxw8KwMUz8m18bgLyH3BCI=</Signature>
<SignatureVersion>HMAC_SHA256_V1</SignatureVersion>
</Messages>
I'm using Postman in order to test the API. Following some instructions I found on the internet, I added a Content-Type HTTP header with value text/xml and the SOAPAction HTTP header with value consultaOperaciones as found in the WSDL file.
I've set this body:
<?xml version="1.0"?>
<soap:Envelope
xmlns:soap="http://www.w3.org/2003/05/soap-envelope/"
soap:encodingStyle="http://www.w3.org/2003/05/soap-encoding">
<soap:Body xmlns:m="http://webservices.apl02.redsys.es">
<m:consultaOperacionesRequest>
<Messages>
<Version Ds_Version="0.0">
<Message>
<Transaction>
<Ds_MerchantCode>999008881</Ds_MerchantCode>
<Ds_Terminal>1</Ds_Terminal>
<Ds_Order>5799L</Ds_Order>
<Ds_TransactionType>3</Ds_TransactionType>
</Transaction>
</Message>
</Version>
<Signature>1KoxTgTakbTprzJ2N/e9JJ8yw/C3QzeNafbUMCNGSFM=</Signature>
<SignatureVersion>HMAC_SHA256_V1</SignatureVersion>
</Messages>
</m:consultaOperacionesRequest>
</soap:Body>
</soap:Envelope>
However, when I send the request I receive the following error message:
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<soapenv:Header/>
<soapenv:Body>
<soapenv:Fault>
<faultcode>Server</faultcode>
<faultstring>Internal Error</faultstring>
</soapenv:Fault>
</soapenv:Body>
</soapenv:Envelope>
It's a generic SOAP error message, therefore I think that the problem has to be related to the codification instead of the external service.
Thanks in advance.

Answer 1

In the WSDL file you will see that the XML should be sent as a string:
<element name="consultaOperaciones">
<complexType>
<sequence>
<element name="cadenaXML" nillable="true" type="xsd:string"/>
</sequence>
</complexType>
</element>
Hence the XML sent should be:
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:web="http://webservices.apl02.redsys.es">
<soapenv:Header/>
<soapenv:Body>
<web:consultaOperaciones>
<cadenaXML><![CDATA[
<Messages>
<Version Ds_Version="0.0">
<Message>
<Detail>
<Ds_MerchantCode>999008881</Ds_MerchantCode>
<Ds_Terminal>1</Ds_Terminal>
<Ds_Order>5799L</Ds_Order>
<Ds_TransactionType>3</Ds_TransactionType>
</Detail>
</Message>
</Version>
<Signature>UfECD0KD9Wwo1iqY6PYZoJxw8KwMUz8m18bgLyH3BCI=</Signature>
<SignatureVersion>HMAC_SHA256_V1</SignatureVersion>
</Messages>
]]>
</cadenaXML>
</web:consultaOperaciones>
</soapenv:Body>
</soapenv:Envelope>
Note that we are using CDATA because as mentioned the XML message should be sent as a string based on the WSDL. I have tried running it and got the response:
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<soapenv:Header/>
<soapenv:Body>
<p259:consultaOperacionesResponse xmlns:p259="http://webservices.apl02.redsys.es">
<consultaOperacionesReturn><![CDATA[<Messages><Version Ds_Version="0.0"><Message><ErrorMsg><Ds_ErrorCode>XML0023</Ds_ErrorCode></ErrorMsg></Message></Version></Messages>]]></consultaOperacionesReturn>
</p259:consultaOperacionesResponse>
</soapenv:Body>
</soapenv:Envelope>
This means that your message is being parsed now because there are no server errors and a consultaOperacionesResponse is being sent which looks legit. The error seems to be related to the data being sent but in general the API is working fine as expected.