Soap

Simple Object Access Protocol (SOAP)

The Simple Object Access Protocol (SOAP) is a lightweight protocol for exchanging information in a decentralized, distributed environment. SOAP runs on top of HTTP, so it can be easily integrated into existing web-based applications, and into existing corporate systems, since most firewalls allow communication on the standard HTTP port. As SOAP is an XML format, the results of queries are easily rendered using XSLT or other XML publishing tools.

The following is an iTQL^TM query, represented as a SOAP message, ready for sending to a Kowari^TM server's SOAP endpoint.

	<?xml version='1.0' encoding='UTF-8'?> <SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/1999/XMLSchema-instance" xmlns:xsd="http://www.w3.org/1999/XMLSchema"> <SOAP-ENV:Body> <ns1:executeQueryToString xmlns:ns1="http://mysite.com:8080/webservices/services/ItqlBeanService" SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"> <queryString xsi:type="xsd:string">select $s $p $o from <rmi://mysite.com/server1#> where $s $p $o;</queryString> </ns1:executeQueryToString> </SOAP-ENV:Body> </SOAP-ENV:Envelope>

 

Note - In the above SOAP example, replace mysite.com with the host name for your system.

Sending this query to a SOAP endpoint results in the query being executed, and the results returned. The following is an example of this using Visual Basic^® code.

	Public Function ExecuteQuery(ByVal server, _ ByVal Query As String) As String Rem External tools Dim Serializer As SoapSerializer30 Dim Reader As SoapReader30 Dim Connector As SoapConnector30 Dim EndPointURL As String Dim NameSpace As String EndPointURL = server & "/webservices/services/ItqlBeanService" NameSpace = "http://org.tucana/itql" Rem Make the connection Set Connector = New HttpConnector30 Rem Initialise the properties Connector.Property("Timeout") = 0 Connector.Property("EndPointURL") = EndPointURL Connector.Property("SoapAction") = "executeQueryToString" Rem Connect and create the envelope Connector.Connect Connector.BeginMessage Set Serializer = New SoapSerializer30 Serializer.Init Connector.InputStream Serializer.StartEnvelope Serializer.SoapAttribute "xsi", , "http://www.w3.org/1999/XMLSchema-instance", "xmlns" Serializer.SoapAttribute "xsd", , "http://www.w3.org/1999/XMLSchema", "xmlns" Serializer.StartBody Serializer.StartElement Method, NameSpace, "http://schemas.xmlsoap.org/soap/encoding/", "ns1" Serializer.StartElement "queryString" Serializer.SoapAttribute "type", , "xsd:string", "xsi" Serializer.WriteString Query Serializer.EndElement Serializer.EndElement Serializer.EndBody Serializer.EndEnvelope Connector.EndMessage Set Reader = New SoapReader30 Rem Read the XML result Reader.Load Connector.OutputStream If Not Reader.Fault Is Nothing Then Err.Raise vbObjectError + ERR_SOAP_FAULT, , Reader.FaultString.Text Else ExecuteQuery = Reader.RpcResult.Text End If Set Reader = Nothing Set Serializer = Nothing Set Connector = Nothing End Function