AJAX 'POST' xml request to server

[Pawanpreet Singh]

Hello Eric,
I have tried in sending POST request to a ValidateServlet. Now instead of passing parameter in queryString, i passed a parameter in req.send("id="+value) like method call. I did this much. but i want to send xml format data in POST. Can i do that.

Please help me in this case

[Yuriy Zilbergleyt]

I think you'd just send the XML as the string parameter in req.send():

req.send("<root><node id='node1' >test</node><node id='node2'>text2</node></root>");

How you build the string is obviously up to you.

-Yuriy

[Eric Pascarello]

Set the content type...
reqXML.setRequestHeader("Content-Type", "text/xml")

Eric

[Pawanpreet Singh]

Thanks Eric, I

[Yuriy Zilbergleyt]

My mistake. That's why I go here, learn something new every day

-Yuriy

[Pawanpreet Singh]

Hi Eric,
I have done so for by use of POST request. The code is given below

function validate(xml) {
var url = "ajaxUpdate";//?id="+xml;

if (window.XMLHttpRequest) {// Non - IE browsers
req = new XMLHttpRequest();
} else if (window.ActiveXObject) { // IE browser
req = new ActiveXObject("Microsoft.XMLHTTP");
}
req.open("POST", url, true);
req.setRequestHeader("Content-Type", "text/xml");
req.onreadystatechange = callback;
req.send("id="+xml);
}
As the code given, i am sending xml formatted string in req.send(..) where as parameter is id, i am getting null on server side. But in case i use same id parameter in very first statement
<b>var url = "ajaxUpdate";//?id="+xml;</b> by removing comments on id. So in this way i receive same value on server side. And i also set
req.send(null) in this case.

Is this right way for sending.

Second thing, if i received xml or any type of post data in this way, i could not take attribute in xml, as u know attribute, we need equals sign and as i am using = sign for parameter id,
so by writing like this :

var url = "ajaxUpdate?id=<message name='pawan'>one</message";
it means there are two parameters one is id and second is name, Is there any way to remove this problem.

[Eric Pascarello]

If you do this, you use the query string to get the values

var url = "ajaxUpdate.jsp?id=asdf";
reqXML.open("GET", url, true);
reqXML.send(null)

If you do this, you use the form to get the value

var url = "ajaxUpdate.jsp";
reqXML.open("POST", url, true);
reqXML.setRequestHeader('Content-Type','application/x-www-form-urlencoded'); 
reqXML.send("id=asdf")

if you want to send xml back, it would be like:

var url = "ajaxUpdate.jsp";
reqXML.open("POST", url, true);
reqXML.setRequestHeader("Content-Type", "text/xml")
reqXML.send("<?xml version='1.0' encoding='UTF-8'?><entry><item>asdf</item></entry>");

Well I am off to bed, not sure if this shed any light on the matter.

Eric
[ July 18, 2005: Message edited by: Eric Pascarello ]

[Pawanpreet Singh]

Thanks Eric again,

Please also put light on this point,
posted July 18, 2005 10:42 PM
--------------------------------------------------------------------------------
If you do this, you use the query string to get the values

code:
--------------------------------------------------------------------------------

var url = "ajaxUpdate.jsp?id=asdf";reqXML.open("GET", url, true);reqXML.send(null)

--------------------------------------------------------------------------------



If you do this, you use the form to get the value

code:
--------------------------------------------------------------------------------

var url = "ajaxUpdate.jsp";reqXML.open("POST", url, true);reqXML.setRequestHeader('Content-Type','application/x-www-form-urlencoded'); reqXML.send("id=asdf")

--------------------------------------------------------------------------------


********if you want to send xml back, it would be like:********

code:
--------------------------------------------------------------------------------

var url = "ajaxUpdate.jsp";reqXML.open("POST", url, true);reqXML.setRequestHeader("Content-Type", "text/xml")reqXML.send("<?xml version='1.0' encoding='UTF-8'?><entry><item>asdf</item></entry>");

How could we get this xml data on server end, as we use request.getParameter(..) for getting data, so what object we use on server side in our jsp for getting this xml string.

Thanks and Regards,
Pawan

[Eric Pascarello]

When you post the xml document to the server, you need to use an input stream to retrieve it. I do not know how to do it in jsp, but .NET would look like:

Dim x As XmlReader = New XmlTextReader(Request.InputStream)
Dim strX As String = x.Read.ToString
Dim xmlDoc As XmlDocument = New XmlDocument
xmlDoc.Load(x)

Eric
[ July 19, 2005: Message edited by: Eric Pascarello ]

[Bear Bibeault]

Once the request gets tot he server there's nothing special about it. In other words, there doesn't need to be any special processing because you are using XMLHttpRequest on the client side.

So you are able to process the request in your servlet just like any other POST operation.

[Lasse Koskela]

Dim x As XmlReader = New XmlTextReader(Request.InputStream)
Dim strX As String = x.Read.ToString
Dim xmlDoc As XmlDocument = New XmlDocument
xmlDoc.Load(x)

[/qb]<hr></blockquote>
Without compiling/testing, it would look something like the following:

// first read the request's body into an in-memory buffer
ByteArrayOutputStream buffer = new ByteArrayOutputStream();
InputStream source = request.getInputStream();
int r = -1;
while ((r = source.read()) != -1) {
    buffer.write(r);
}
// and then feed the buffer's contents to DocumentBuilder
DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
Document xmlDoc = builder.parse(new ByteArrayInputStream(buffer.getBytes()));

[ July 19, 2005: Message edited by: Eric Pascarello ]