in reply to Re: Perl web service consumed by c# client returns null.
in thread Perl web service consumed by c# client returns null.

So now you got me really confused.

The text beginning with Exception: System.InvalidOperationException: looks as if it is printed by the C# client, as Perl doesn't throw such an exception. The stack trace at the end also looks rather C#-ish to me. So who is composing the "error message" enclosed by the two -- strings, and from what input? You write I have added this line in the perl web service - but apparently the client embedded it into its "error message."

The string printed by print "\nContent-type : text/xml\n\n" useless for debugging, it is just a constant. If you send it to the client, then it breaks the HTTP response. You should at least do something like that:

print "HTTP/1.1 200 OK\n;
print "Content-type : text/plain\n\n";

[download]

...because after inserting these lines, the content type of the response is no longer valid XML, but can still be read as text.

You could, of course, also point a simple client like LWP's HEAD program to the service to check whether the response is well-formed.

Replies are listed 'Best First'.
Re^3: Perl web service consumed by c# client returns null.
by Anonymous Monk on Dec 13, 2019 at 09:58 UTC

    Hi Haj,
    when I added print "Content-type : text/xml\n\n" in perl webservice, after this there is no content-type error but I am getting below error

    Exception: System.InvalidOperationException: Response is not well-form
+ed XML. ---> System.Xml.XmlException: Data at the root level is inval
+id. Line 1,
 position 1.
   at System.Xml.XmlTextReaderImpl.Throw(Exception e)
   at System.Xml.XmlTextReaderImpl.ParseRootLevelWhitespace()
   at System.Xml.XmlTextReaderImpl.ParseDocumentContent()
   at System.Xml.XmlReader.MoveToContent()
   at System.Web.Services.Protocols.SoapHttpClientProtocol.ReadRespons
+e(SoapClientMessage message, WebResponse response, Stream responseStr
+eam, Boolea
n asyncCall)
   at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(Stri
+ng methodName, Object[] parameters)
   --- End of inner exception stack trace ---
   at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(Stri
+ng methodName, Object[] parameters)
   at Search.MRWebServices__search(String usr, String pw, String extra
+Info, String query)
   at main.Main()

    [download]

    Thank you

[reply]
[d/l]
      Exception: System.InvalidOperationException: Response is not well-formed XML. ---> System.Xml.XmlException: Data at the root level is invalid. Line 1, position 1

      So whatever you send to C# is not valid ("well-formed") XML. The problem is found at the first character in the first line, at the root element. See XML and Well-formed document.

      Alexander

      --
      Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)
[reply]

      Please read carefully what I wrote in my previous response.

      If you print an extra header, then the rest - which contains another HTTP header - is no longer valid XML.

      Now, what happens if you just don't print your own Content-Type header?

[reply]

        If I don't print my own Content-type, I get below client side exception

        Exception: System.ArgumentNullException: Array cannot be null.
Parameter name: bytes
   at System.Text.Encoding.GetString(Byte[] bytes)
   at main.Main()

        [download]

[reply]
[d/l]

In Section Seekers of Perl Wisdom