CODEWITHSUNDEEP
delphisoapwininet
jrodenhi
jrodenhi

Reputation: 2237

Posting Data and Getting Response for SOAP Client

Almost all of my development experience has been in desktop applications. I am currently using Delphi 2010 and I need to write a SOAP client to access the web service that the California EDD maintains for electronically handling payroll data. I gave up on the Delphi WSDL Importer because there was too much happening behind the curtain and I did not seem to be able to make any progress. I downloaded Fiddler2 and have been using that to view what I have been writing to the web. I found this procedure for posting and I feel that I am getting somewhere now.

//from StackOverflow Andreas Rejbrand 06/04/2012
procedure WebPostData(const UserAgent: string; const Server: string; const Resource: string; const Data: AnsiString); overload;
    var
      hInet: HINTERNET;
      hHTTP: HINTERNET;
      hReq: HINTERNET;
    const
      accept: packed array[0..1] of LPWSTR = (PChar('*/*'), nil);
      header: string = 'Content-Type: text/plain';
    begin
      hInet := InternetOpen(PChar(UserAgent), INTERNET_OPEN_TYPE_PRECONFIG, nil, nil, 0);
      try
        hHTTP := InternetConnect(hInet, PChar(Server), INTERNET_DEFAULT_HTTP_PORT, nil, nil, INTERNET_SERVICE_HTTP, 0, 1);
        try
          hReq := HttpOpenRequest(hHTTP, PChar('POST'), PChar(Resource), nil, nil, @accept, 0, 1);
          try
            if not HttpSendRequest(hReq, PChar(header), length(header), PChar(Data), length(Data)) then
              raise Exception.Create('HttpOpenRequest failed. ' + SysErrorMessage(GetLastError));
          finally
            InternetCloseHandle(hReq);
          end;
        finally
          InternetCloseHandle(hHTTP);
        end;
      finally
        InternetCloseHandle(hInet);
      end;
    end;

I changed the Content-Type because the original seemed to never return.

I have been calling it like this:

procedure TForm1.Button1Click(Sender: TObject);
var sl: TStringList;
    s: String;
begin
  sl := TStringList.Create;
  sl.LoadFromFile('C:\Documents and Settings\Jack\Desktop\My Reading\FSET Development\Ping.xml');
  s := sl.Text;
  sl.Free;
  WebPostData('BNWebSvc', 'FSETTESTPROD.EDD.CA.GOV','fsetservice', s);
end;

In my browser, the host (FSETTESTPROD.EDD.CA.GOV) exists and responds that it is available. When I post, I get a 404 error maybe because the web service name is appended. In Fiddler2, the output looks like this:

POST http://FSETTESTPROD.EDD.CA.GOV/fsetservice HTTP/1.1
Accept: */*
Content-Type: text/plain
User-Agent: BNWebSvc
Host: FSETTESTPROD.EDD.CA.GOV
Content-Length: 2190
Pragma: no-cache
Cookie: __utma=158387685.1851397844.1321382260.1321382260.1321382260.1; __utmz=158387685.1321382260.1.1.utmcsr=google|utmccn=(organic)|utmcmd=organic|utmctr=calif%20edd%20eft%20payroll%20processor%20batch%20processing

<?xml version="1.0" encoding="utf-8"?>
<log>
  <inputMessage utc="3/2/2007 10:45:44 PM" messageId="urn:uuid:c07c9aef-28db-4843-8dfc-c5b4d3dc363b">
    <processingStep description="Unprocessed message">
      <soap:Envelope xmlns:xop="http://www.w3.org/2004/08/xop/include" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:wsa="http://schemas.xmlsoap.org/ws/2004/08/addressing" xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd" xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd">
        <soap:Header>
          <wsa:Action>//edd.ca.gov/Ping</wsa:Action>
          <wsa:MessageID>urn:uuid:c07c9aef-28db-4843-8dfc-c5b4d3dc363b</wsa:MessageID>
          <wsa:ReplyTo>
            <wsa:Address>http://schemas.xmlsoap.org/ws/2004/08/addressing/role/anonymous</wsa:Address>
          </wsa:ReplyTo>
          <wsa:To>http://localhost:3031/EDD.DMRC.FSET.WebServices/FsetService.asmx</wsa:To>
          <wsse:Security soap:mustUnderstand="1">
            <wsu:Timestamp wsu:Id="Timestamp-0983e8c1-e822-4648-8066-33839f54a6a0">
              <wsu:Created>2007-03-02T22:45:41Z</wsu:Created>
              <wsu:Expires>2007-03-02T22:50:41Z</wsu:Expires>
            </wsu:Timestamp>
            <wsse:UsernameToken xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd" wsu:Id="SecurityToken-0d55d82c-d16d-4c0e-826b-21bf7c805a0f">
              <wsse:Username>MyUserName</wsse:Username>
              <wsse:Password Type="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-username-token-profile-1.0#PasswordText">MyPassword</wsse:Password>
              <wsse:Nonce>w6dgDz1DMzKntFsFdEcjhw==</wsse:Nonce>
              <wsu:Created>2007-03-02T22:45:41Z</wsu:Created>
            </wsse:UsernameToken>
          </wsse:Security>
        </soap:Header>
        <soap:Body>
          <Ping xmlns="http://edd.ca.gov/">
          </Ping>
        </soap:Body>
      </soap:Envelope>
    </processingStep>
  </inputMessage>
</log>

I will need to send this using HTTPS when this is working and I probably need to incorporate that to get it working.

Am I going in the right direction?

The procedure from Andreas did not indicate how to retrieve the response. How do I retrieve the response?

Upvotes: 4

Views: 5523

Answers (2)

jrodenhi
jrodenhi

Reputation: 2237

I have now done more research, bought a decent book on web services "Teach Yourself Web Services" (thank you rooted Nook), and spoke briefly with someone at the agency whose web service I am attempting to use. So I think I have some answers to the questions I have been asking and I will summarize them here in case it is helpful for anyone else starting down this same path. If you see that I have misstated something and you can correct or improve it, I would appreciate it if you would take the time to enter your improvements.

In the graphics where it is shown that web services ride on HTTP it means that if you are using a component that can make a request to a website, you can probably also use it to create a web service client.

You should probably install Fiddler2 right away. The feedback you will get from it will be essential to making progress.

A WSDL file may be helpful to create a web services client but maybe not. My experience with the Delphi WSDL importer is that it does an incomplete job. The Wikipedia article on web services has a section on Big Web Services that points out that the WSDL file is not necessary but can help automate the design of a web service client. If it isn't helpful, don't use it.

You don't need to use the HTTPRIO component to access a web service. You can use the WinInet unit with some code like above that I plagiarized from some StackOverflow postings.

The schemas referenced in the WSDL file don't have to exist at the locations shown. Technically, these are URIs rather than URLs (identifiers rather than locations).

Writing a web service client by hand may be an acceptable alternative to automatic generation when the automatic generation doesn't work. Besides, like so many black box solutions, it only works when it works. When it doesn't work, there may be no other choice. Also, you will learn more and have better control over the output.

Sending your request using SSL seems to be automatic if you use the the PostWebData routine above. Getting the response is also included in this routine.

Getting the two responses I got from the web service seems to be indicating that my process is good but my content is bad. I now have to look into the actual SOAP envelope and supply acceptable data to go to the next step.

If the results are not decrypted when I complete that next step, then I will have to do more research.

I hope this is helpful for someone else trying to find his or her way in web services.

Upvotes: 0

jrodenhi
jrodenhi

Reputation: 2237

I think I am making some progress. I changed WebPostData into a function and copied some code from elsewhere to use SSL and to return a result. It now looks like this:

function WebPostData(const UserAgent: string; const Server: string; const Resource: string; const Data: AnsiString): String;
var
  hInet: HINTERNET;
  hHTTP: HINTERNET;
  hReq: HINTERNET;
  BufStream: TMemoryStream;
  BytesRead: Cardinal;
  aBuffer     : Array[0..4096] of Char;
  flags       : DWord;
const
  accept: packed array[0..1] of LPWSTR = (PChar('*/*'), nil);
  header: string = 'Content-Type: text/plain';
begin
  hInet := InternetOpen(PChar(UserAgent), INTERNET_OPEN_TYPE_PRECONFIG, nil, nil, 0);
  try
    hHTTP := InternetConnect(hInet, PChar(Server), INTERNET_DEFAULT_HTTPS_PORT, nil, nil, INTERNET_SERVICE_HTTP, 0, 1);
    try
      flags := INTERNET_FLAG_SECURE or INTERNET_FLAG_KEEP_CONNECTION;
      hReq := HttpOpenRequest(hHTTP, PChar('POST'), PChar(Resource), nil, nil, @accept, flags, 1);
      try
        if not HttpSendRequest(hReq, PChar(header), length(header), PChar(Data), length(Data)) then begin
          raise Exception.Create('HttpOpenRequest failed. ' + SysErrorMessage(GetLastError));
        end else begin
           BufStream := TMemoryStream.Create;
            try
              while InternetReadFile(hReq, @aBuffer, SizeOf(aBuffer), BytesRead) do
              begin
                if (BytesRead = 0) then Break;
                BufStream.Write(aBuffer, BytesRead);
              end;

              aBuffer[0] := #0;
              BufStream.Write(aBuffer, 1);
              Result := PChar(BufStream.Memory);
            finally
              BufStream.Free;
            end;
        end;
      finally
        InternetCloseHandle(hReq);
      end;
    finally
      InternetCloseHandle(hHTTP);
    end;
  finally
    InternetCloseHandle(hInet);
  end;
end;

And I now get two results in Fiddler, one successful and one not.

The successful one:

CONNECT fsettestprod.edd.ca.gov:443 HTTP/1.0
User-Agent: BNWebSvc
Host: FSETTESTPROD.EDD.CA.GOV:443
Content-Length: 0
Connection: Keep-Alive
Pragma: no-cache

A SSLv3-compatible ClientHello handshake was found. Fiddler extracted the parameters below.

Major Version: 3
Minor Version: 1
Random: 4F 28 1F 92 96 EA 2C 64 91 59 12 84 D1 F3 F8 ED BA 89 A5 44 94 D6 50 E0 CF 9B FA 12 5F 57 AD EB
SessionID: empty
Ciphers: 
    [0004]  SSL_RSA_WITH_RC4_128_MD5
    [0005]  SSL_RSA_WITH_RC4_128_SHA
    [000A]  SSL_RSA_WITH_3DES_EDE_SHA
    [0009]  SSL_RSA_WITH_DES_SHA
    [0064]  TLS_RSA_EXPORT1024_WITH_RC4_56_SHA
    [0062]  TLS_RSA_EXPORT1024_WITH_DES_SHA
    [0003]  SSL_RSA_EXPORT_WITH_RC4_40_MD5
    [0006]  SSL_RSA_EXPORT_WITH_RC2_40_MD5
    [0013]  SSL_DHE_DSS_WITH_3DES_EDE_SHA
    [0012]  SSL_DHE_DSS_WITH_DES_SHA
    [0063]  TLS_DHE_DSS_EXPORT1024_WITH_DES_SHA

And the unsuccessful one:

POST https://FSETTESTPROD.EDD.CA.GOV/fsetservice HTTP/1.1
Accept: */*
Content-Type: text/plain
User-Agent: BNWebSvc
Host: FSETTESTPROD.EDD.CA.GOV
Content-Length: 2190
Connection: Keep-Alive
Cache-Control: no-cache
Cookie: __utma=158387685.1851397844.1321382260.1321382260.1321382260.1; __utmz=158387685.1321382260.1.1.utmcsr=google|utmccn=(organic)|utmcmd=organic|utmctr=calif%20edd%20eft%20payroll%20processor%20batch%20processing

<?xml version="1.0" encoding="utf-8"?>
<log>
  <inputMessage utc="3/2/2007 10:45:44 PM" messageId="urn:uuid:c07c9aef-28db-4843-8dfc-c5b4d3dc363b">
    <processingStep description="Unprocessed message">
      <soap:Envelope xmlns:xop="http://www.w3.org/2004/08/xop/include" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:wsa="http://schemas.xmlsoap.org/ws/2004/08/addressing" xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd" xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd">
        <soap:Header>
          <wsa:Action>//edd.ca.gov/Ping</wsa:Action>
          <wsa:MessageID>urn:uuid:c07c9aef-28db-4843-8dfc-c5b4d3dc363b</wsa:MessageID>
          <wsa:ReplyTo>
            <wsa:Address>http://schemas.xmlsoap.org/ws/2004/08/addressing/role/anonymous</wsa:Address>
          </wsa:ReplyTo>
          <wsa:To>http://localhost:3031/EDD.DMRC.FSET.WebServices/FsetService.asmx</wsa:To>
          <wsse:Security soap:mustUnderstand="1">
            <wsu:Timestamp wsu:Id="Timestamp-0983e8c1-e822-4648-8066-33839f54a6a0">
              <wsu:Created>2007-03-02T22:45:41Z</wsu:Created>
              <wsu:Expires>2007-03-02T22:50:41Z</wsu:Expires>
            </wsu:Timestamp>
            <wsse:UsernameToken xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd" wsu:Id="SecurityToken-0d55d82c-d16d-4c0e-826b-21bf7c805a0f">
              <wsse:Username>***MyUserName***</wsse:Username>
              <wsse:Password Type="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-username-token-profile-1.0#PasswordText">***MyPassword***</wsse:Password>
              <wsse:Nonce>w6dgDz1DMzKntFsFdEcjhw==</wsse:Nonce>
              <wsu:Created>2007-03-02T22:45:41Z</wsu:Created>
            </wsse:UsernameToken>
          </wsse:Security>
        </soap:Header>
        <soap:Body>
          <Ping xmlns="http://edd.ca.gov/">
          </Ping>
        </soap:Body>
      </soap:Envelope>
    </processingStep>
  </inputMessage>
</log>

I stepped through my code and watched Fiddler react. Both messages came when I stepped over the HTTPSendRequest line. In my button click event, I assign the results of the function to a memo control, but all I get are a bunch of squares indicating unprintable characters.

Does the result I am getting indicate that the process is good but the content is bad?

Could this still be a problem because you can't access a WebService this way?

How can I decrypt the results or will this happen automatically when I get the process right?

Upvotes: 1

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