Download data through Web Service

Question

Hi All,
We have a requirement to download data from SAP system to our Oracle DB. Issue is we will not be able to connect to SAP DB. They weill provide a webservice and we should use that by passing parameters.
My query is, how can we do that in Oracle DB. I want to write a Program unit and call web service whenever required.
Any Idea in this regard will be of great help.
Thanks

Answer 1

Here's some basic skeleton code for doing webservice calls in PL/SQL, to get you started...
-- skeleton code
  PROCEDURE p_soap_request(p_username IN VARCHAR2, p_password IN VARCHAR2, p_proxy IN VARCHAR2) IS
    soap_request  VARCHAR2(30000);
    soap_respond  CLOB;
    http_req      utl_http.req;
    http_resp     utl_http.resp;
    resp          XMLType;
    soap_err      exception;
    v_code        VARCHAR2(200);
    v_msg         VARCHAR2(1800);
    v_len number;
    v_txt Varchar2(32767);
  BEGIN
    UTL_HTTP.SET_PROXY(p_proxy);
    -- Define the SOAP request according the the definition of the web service being called
    soap_request:= '<?xml version = "1.0" encoding = "UTF-8"?>'||
                   '<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">'||
                   '  <SOAP-ENV:Body>'||
                   '    <m:DownloadRequest xmlns:m="http://www.website.net/messages/GetDetails">'||
                   '      <m:UserName>'||p_username||'</m:UserName>'||
                   '      <m:Password>'||p_password||'</m:Password>'||
                   '    </m:DownloadRequest>'||
                   '  </SOAP-ENV:Body>'||
                   '</SOAP-ENV:Envelope>';
    http_req:= utl_http.begin_request
              ( 'http://www.website.net/webservices/GetDetailsService.asmx'
              , 'POST'
              , 'HTTP/1.1'
    utl_http.set_header(http_req, 'Content-Type', 'text/xml');
    utl_http.set_header(http_req, 'Content-Length', length(soap_request));
    utl_http.set_header(http_req, 'Download', ''); -- header requirements of particular web service
    utl_http.write_text(http_req, soap_request);
    http_resp:= utl_http.get_response(http_req);
    utl_http.get_header_by_name(http_resp, 'Content-Length', v_len, 1); -- Obtain the length of the response
    FOR i in 1..CEIL(v_len/32767) -- obtain response in 32K blocks just in case it is greater than 32K
    LOOP
        utl_http.read_text(http_resp, v_txt, case when i < CEIL(v_len/32767) then 32767 else mod(v_len,32767) end);
        soap_respond := soap_respond || v_txt; -- build up CLOB
    END LOOP;
    utl_http.end_response(http_resp);
    resp:= XMLType.createXML(soap_respond); -- Convert CLOB to XMLTYPE
  END;