- From: Anish Karmarkar <Anish.Karmarkar@oracle.com>
- Date: Tue, 07 Feb 2006 22:44:37 -0800
- To: Christopher B Ferris <chrisfer@us.ibm.com>
- CC: xml-dist-app@w3.org
I don't quite see the value in requiring steps 1, 2 and 3 if a 202 is returned. This restricts services from receiving 'one-way' messages and processing them off-line, do batch-processing of messages or store it in a queue. Since we are talking about an MEP (request-optional-response) that optionally allows the service to return a SOAP message (or not). If the service does indeed performs steps 1, 2 or 3 and generates a fault before/during those steps it is free to send a fault back with a 4xx/5xx status code. The client has to always wait for a HTTP response. On getting a 202 back the client should not assume anything (about SOAP processing), as the non-committal nature of 202 indicates, other than the fact that the bytes were transfer correctly and that the message was a correct HTTP message (with the correct/expected HTTP headers). -Anish -- Christopher B Ferris wrote: > > I think that this issue from ws-a wg has relevance to our work on the > binding, > > In reviewing the current text and tables in part 2, it isn't clear to me > that there is > an established and well defined relationship between the request and > response > messages with regards to the SOAP processing model. > > e.g. it doesn't say anywhere whether the SOAP processing as described > in part 1 sect 2.6 MUST be performed BEFORE the "response message" > in the Request Response MEP is made available in the outputMessage > property. > > As I indicated in my response to Marc on the ws-a list, I think that at a > minimum, any response, whether SOAPy or not, should be made only > AFTER steps 1, 2 and 3 as defined in section 2.6 of part 1 have been > completed so that any mU faults can be transmitted even if the actual > processing of the headers (and the body) are to be deferred. > > Thoughts? > > Christopher Ferris > STSM, Emerging e-business Industry Architecture > email: chrisfer@us.ibm.com > blog: http://www.ibm.com/developerworks/blogs/dw_blog.jspa?blog=440 > phone: +1 508 377 9295 > ----- Forwarded by Christopher B Ferris/Waltham/IBM on 01/31/2006 12:49 > PM ----- > > public-ws-addressing-request@w3.org wrote on 01/31/2006 11:53:27 AM: > > > > > Marc, > > > > Good question. > > > > Given that a 202 response is not related to the *processing* of the > > request message, one could > > conclude that any SOAP envelope carried in the 202 Accepted response > > might not necessarily > > have a relationship with the request message at all. However, given > > what Mark observed, I suspect > > that we might do well to specify that at a minimum, the SOAP > > processing w/r/t SOAP headers > > MUST be performed before any response is generated, so as to ensure > > that if a mU fault > > is generated, it can be transmitted on the HTTP response (with a 500). > > > > So, my inclination would be (b) > > > > Cheers, > > > > Christopher Ferris > > STSM, Emerging e-business Industry Architecture > > email: chrisfer@us.ibm.com > > blog: http://www.ibm.com/developerworks/blogs/dw_blog.jspa?blog=440 > > phone: +1 508 377 9295 > > > > public-ws-addressing-request@w3.org wrote on 01/31/2006 10:22:51 AM: > > > > > > > > Mark Baker wrote: > > > > On 1/31/06, David Hull <dmh@tibco.com> wrote: > > > >> We've been pretty clear for a while that empty 202 means "ack". > I'm > > > >> hearing that non-empty 202 is meant for things like WS-RX acks, > > but I'm not > > > >> sure this is nailed down. There seems to be some possibility > that a 202 > > > >> with a SOAP envelope could also be a real response. > > > > > > > > It's still a response, just not the result of processing the request. > > > > > > > > So if you took a SOAP envelope and sent it as an HTTP response with a > > > > 202 code, it would mean something entirely different than if sent > back > > > > with a 200 code... in the same way that a SOAP fault sent with 200 > > > > means something entirely different than a SOAP fault > > > > > > > Right, this chimes with my comments on the call last night. The > envelope > > > returned in the HTTP 202 response is something other than a reply > to the > > > envelope sent in the HTTP request. The question I'm struggling with is > > > whether one can assume that the SOAP processing rules have been > followed > > > on the request envelope prior to the response envelope being > returned or > > > not ? E.g. if I include WS-Addr header blocks in the request envelope, > > > can I assume that the 202 response envelope will contain the expected > > > WS-Addr header blocks (e.g. relationship(msgid)). If the SOAP > processing > > > rules haven't been followed then what process lead to the > generation of > > > the 202 response envelope ? We've been using WS-RX as a use case but, > > > AFAIK, WS-RX uses header blocks and relies on the SOAP processing > model > > > too so are we inventing a new two-stage SOAP processing model or what ? > > > > > > In a nutshell, I think we need to decide whether the 202 response > > > envelope is returned: > > > > > > (a) Before SOAP header block and SOAP Body processing, or > > > (b) After SOAP header block processing but before SOAP Body > processing, or > > > (c) (for completeness although this seems to contradict the 'Accepted' > > > semantics of HTTP 202) After SOAP header block and SOAP Body > processing. > > > > > > Thoughts ? > > > > > > Marc. > > > > > > >> If 202 can be a real response, then one would have to use > > > something besides > > > >> 202 to figure out what's really going on (e.g., whether the > > > message consists > > > >> only of WS-RX headers and similar). In this case 202 isn't > > really carrying > > > >> any information and why bother allowing for it? On the other > > hand, if 202 > > > >> means something in particular, then what exactly does it mean? > > > > > > > > Just what it says in the HTTP spec. > > > > > > > >> As far as I can tell, the value in non-empty 202 is telling > > the SOAP stack > > > >> "Hey, this is just infrastructure stuff. Don't pass it along to the > > > >> application." We can't say that here, but we could (probably) > say it > > > >> elsewhere. > > > > > > > > 202, like 200, is a symbol with application layer semantics, and as > > > > such, it should be exposed to the application (plus the SOAP 1.2 HTTP > > > > binding is a *transfer* binding). In the case of 202, the > application > > > > needs to know that no subsequent message which includes "the results > > > > of processing" of the initial request, is necessarily forthcoming > (and > > > > won't be without additional agreement). > > > > > > > > BTW, I just noticed this part of the 202 spec which should > probably be > > > > highlighted; > > > > > > > > "The entity returned with this > > > > response SHOULD include an indication of the request's current > status > > > > and either a pointer to a status monitor or some estimate of > when the > > > > user can expect the request to be fulfilled." > > > > > > > > Which suggests that a URI could be returned upon which the > application > > > > could invoke GET to determine the state of the processing of the > > > > request (anybody remember CORBA "Futures"?). > > > > > > > > Mark. > > > > > > > > > >
Received on Wednesday, 8 February 2006 06:44:56 UTC