[Seaside] WAResponse and XML

Thu Aug 4 18:41:47 UTC 2011

On Aug 4, 2011, at 8:04 AM, Philippe Marschall wrote:

> 2011/8/4 Jay Hardesty <jayh at panix.com>:
>> 
>> Hi - I'm having a problem returning XML as a response from within a Seaside app, after moving to 3.0.
>> 
>> I used to return XML by:
>> 
>>        self session returnResponse:
>>                (WAResponse new
>>                        contentType: 'text/xml';
>>                        nextPutAll: xmlString;
>>                        yourself)
>> 
>> but t in Seaside 3.0 I get:
>>        'You can no longer return a new WAResponse instance. You must instead modify the Response contained in the active RequestContext. Look for senders of #respond: and #response for examples.'
>> 
>> 
>> Following the nearest examples I can find I tried:
>> 
>>        self requestContext respond: [:response |
>>                | document |
>>                document := MIMEDocument
>>                        contentType: 'text/xml';
>>                        content: xmlString.
>>                response document: document]
>> 
>> and:
>> 
>>        self requestContext respond: [:response |
>>                response
>>                        contentType: 'text/xml';
>>                        nextPutAll: xmlString]
>> 
>> but in both cases an html document arrives downstream (with XML in the body) rather than the XML itself as previously
>> 
>> Think I'm missing something basic here... Thanks very much for any pointers,
> 
> That should absolutely work. The sample code below works for me.
> You'll probably want to test with Firefox because it renders XML
> nicely.
> 
> renderContentOn: html
> 	html anchor
> 		callback: [
> 			self requestContext respond: [ :response |
> 				response
> 					contentType: 'text/xml';
> 					nextPutAll: '<?xml version="1.0"
> encoding="UTF-8"?><hello><world/></hello>' ] ];
> 		with: 'XML'
> 
> Cheers
> Philippe
> _______________________________________________
> seaside mailing list
> seaside at lists.squeakfoundation.org
> http://lists.squeakfoundation.org/cgi-bin/mailman/listinfo/seaside

Thank you Phillipe - Yes, your code works for me just as you described.

I guess my problem is that I want my renderContentOn: to immediately return XML in certain circumstances without any user action.  As in this variation on your code example:

	renderContentOn: html	
		self requestContext respond: [ :response |
			response
				contentType: 'text/xml';
				nextPutAll: '<?xml version="1.0" encoding="UTF-8"?><hello><world/></hello>' ] 

If I call this from Firefox, then instead of XML (as in your example) I see
	"XML Parsing Error: XML or text declaration not at start of entity[...]"   
and viewing the page source gives: 
	"<!DOCTYPE html PUBLIC [...]"

Whereas my old code:

	renderContentOn: html
		self session returnResponse: 
			(WAResponse new
				contentType: 'text/xml';
				nextPutAll: <?xml version="1.0" encoding="UTF-8"?><hello><world/></hello>' ;
				yourself)

returned and displayed XML just as your example, but without any user action

So what I'm apparently missing is whatever magic happens as a result of the anchor callback being fired in your example.  I wonder if there's any way to get that kind of callback behavior programatically(?)

> What do you mean with non-Seaside client? Is it a non-browser
> application, non-HTML application? I

Yes, I'm using Seaside apps to serve (music score data) to
- Seaside web client
- Flash web client
- iPhone app
- code running in Second Life
- Croquet environment

> In those cases you can still use
> Seaside. You can either directly write RequestHandlers or you can have
> a look at Seaside-REST.

Interesting - I'll try to find an example using WARequestHandler, though I suppose this will mean moving the functionality out of my Seaside app (WAComponent subclass)...

Thanks very much for the tips, and for your example which has helped me narrow the scope of the problem

Best regards
Jay