atom feed17 messages in org.oasis-open.lists.wsrpRe: [wsrp] Client header propagation ...
FromSent OnAttachments
Subbu AllamarajuFeb 12, 2007 10:56 am 
Subbu AllamarajuFeb 13, 2007 12:12 pm 
Rich ThompsonFeb 13, 2007 12:30 pm 
Stefan HepperFeb 14, 2007 12:59 am 
Michael FreedmanFeb 14, 2007 10:09 am 
Subbu AllamarajuFeb 14, 2007 10:18 am 
Michael FreedmanFeb 14, 2007 12:34 pm 
Subbu AllamarajuFeb 14, 2007 12:56 pm 
Michael FreedmanFeb 14, 2007 3:18 pm 
Richard JacobFeb 15, 2007 11:30 am 
Richard JacobFeb 15, 2007 11:31 am 
Richard JacobFeb 15, 2007 11:32 am 
Richard JacobFeb 15, 2007 11:34 am 
Richard JacobFeb 15, 2007 11:36 am 
Subbu AllamarajuFeb 15, 2007 11:54 am 
Michael FreedmanFeb 15, 2007 12:18 pm 
Richard JacobFeb 16, 2007 2:50 am 
Subject:Re: [wsrp] Client header propagation to user-agents
From:Richard Jacob (rich@de.ibm.com)
Date:Feb 15, 2007 11:36:47 am
List:org.oasis-open.lists.wsrp

I agree with Mike here. I think we should drop that use case from the spec for now. JSR286 allows cookies to flow from/to the portlet, but client side manipulation of that cookies is not mandated there, too. Is this a new use case you'd like to bring into JSR286?

Mit freundlichen Gruessen / best regards,

Richard Jacob

______________________________________________________ IBM Lab Boeblingen, Germany Dept. 2289, WebSphere Portal Server Development 1 WSRP Team Lead WSRP Architecture & Standardization Phone: ++49 7031 16-3469 - Fax: ++49 7031 16-4888 Email: mailto:rich@de.ibm.com

Michael Freedman <michael.freedman @oracle.com> To wsrp <ws@lists.oasis-open.org> 02/15/07 12:17 AM cc

Subject Re: [wsrp] Client header propagation to user-agents

Yes, I was looking for something that was viable and would actually work for most/all use cases. Without that I don't see the value in doing this, particularly in spec. As you already require some indication the code knows its running in a portlet environment (because you require the namespace tag) -- how about defining a specific format for the consumer to encode the value field so that clients can extract their original values. Obviously a pain in client side handling being different for the portlet case but at least you avoid the problem of support being called and told there is an intermittent problem where certain fields on the page sometimes act screwy....all because of the variability of consumer cookie caching support. -Mike-

Subbu Allamaraju wrote:

The comment parameter is not part of the "Cookie" header. So, when Consumer receives the cookie, it does not get back the comment.

Here are the options:

a. Currently, consumers implement some kind of cookie store to store init cookies. Those consumers can be extended to store cookie mapping info for the duration of the consumer's runtime.

b. Support a persistent cookie-store on the consumer. Consumers in (a) are most likely ignoring the lifetime semantics of init cookies anyway, and would benefit from a persistent store.

Supporting (b) definitely takes some extra work, and consumers can choose to go with (a) instead.

Subbu

Michael Freedman wrote:

Well then maybe the Comment field?

Subbu Allamaraju wrote:

Because, the value needs to be preserved if we want to allow client-side access.

Subbu

Michael Freedman wrote:

Why wouldn't the consumer rewrite the value field of the producer cookie to wrap the producer's value along with this mapping data so everything is transported in a single cookie? -Mike-

I think storing the mapping information not with the cookie will also not work as general solution as you need to store them for as long as the cookie lifetime which is quite a hard requirement for some consumers.

Good points.

From an implementation point of view, setting a companion cookie is an option. However, as you point out, there are browser limits on the number of cookies stored per domain (starting from IE's 20 to Safari's 1000+).

Two possible solutions:

a. Store the mapping information locally on the consumer b. Require some metadata from the producer on each cookie whether it needs to be proxied to the browser or not

In general, storing mapping info in cookies may not be work out. When cookie limits are reached, browser will start dropping some cookies, and the consumer may lose the mapping information forever.

Subbu

Stefan Hepper wrote:

Hi Subbu, with requiring that you re-write each cookie and that duplicate each cookie on the client as you also require to remember somehow the original domain, path, port. Given that the recommendation is to allow storing 20 cookies per web server this would mean that only 10 cookies per consumer are likely to be supported. Isn't that quite restrictive? That would only be needed if you really want to access the cookies on the client, so maybe it would make sense that the consumer indicates if that is really the case or not and thus allow the consumer to make the re-writing accordingly. Also the namespacing is only needed for the client access use case.

During last week's interfaces call, I was asked to outline a proposal to extend header propagation all the way to the user agent. This is in addition to the proposal submitted by Rich last week to transport such headers within the protocol.

Here is a quick summary of the text below.

The Set-Cookie/Set-Cookie2 headers can contain "name", "value", "comment", "domain", "max-age", "pat", secure", "version", "discard", and "port" attributes.

The proposal is to require the Producer to use the namespacePrefix for generating the cookie name, and require the Consumer to rewrite the "domain", "path", and "port" parameters.

(The "port" parameter is introduced RFC 2965 as part of the Set-Cookie2 header. This is not widely used.)

The net benefits of this proposal are:

- Portlets can write script to access state contained in cookies. This opens up the door to support more web applications over WSRP.

- Consumers can use browsers as a cookie store instead of managing cookies locally.

Please comment on before the next TC/Interfaces calls.

Subbu

Section 6.1.16 MimeResponse

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

The following rules apply to cookies returned by the Producer via the clientHeaders structure with a name of Set-Cookie or Set-Cookie2. Such clientHeaders correspond to the Set-Cookie and Set-Cookie2 headers specified by RFC 2109 and RFC 2965, and the values of such headers MUST follow RFC 2109 or 2965 for all cookie parameters.

The Producer MUST prefix the names of cookies with the namespacePrefix supplied by the Consumer. When a cookie includes any of domain, path, or port parameters, the Producer MUST ensure that their values correspond to any domain, path or port that it expects the Consumer to submit future requests to. Consumers may ignore cookies whose names and parameters do not follow these statements, as such cookies may conflict with other cookies managed by the Consumer.

When a Consumer receives a clientHeaders element with a name of Set-Cookie or Set-Cookie2, it SHOULD return HTTP headers named Set-Cookie or Set-Cookie2 to the user-agent subjected to its security-policy restrictions in addition to those rules specified by RFCs 2109 and 2965. If the received cookie includes any of domain, path or port parameters, the Consumer MUST replace those with corresponding values for the Consumer such that those values remain valid for the user-agent receiving the cookies. The Consumer MUST use the Producer-supplied values for other parameters.

If the names of clientHeaders received by a Consumer correspond to any caching response headers specified in RFC 2616, the Consumer MUST interpret those headers as guidance related to caching the markup or resource provided by the Producer. The Consumer MAY propagate such headers to the user-agent subjected to its own caching policies.

Note that some Consumer implementations may prohibit transporting clientHeaders received during the markup generation phase to user agents. Portlets counting on user-agents receiving such headers must program themselves to account for this behavior.

Section 6.1.10 ClientData

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

When a Consumer receives Cookie or Cookie2 headers from the user-agent corresponding to cookies previously returned by the Producer via the clientHeaders structure, the Consumer SHOULD include clientHeaders named Cookie or Cookie2 in requests to the Producer subjected to its security-policy restrictions in addition to those rules specified by RFCs 2109 and 2965. If the request from the user-agent corresponds to serve a resource via HTTP, the Consumer SHOULD include corresponding HTTP headers named Cookie or Cookie2 subjected to the same policy. If the Consumer rewrote the domain, path, or port parameters, the Consumer MUST replace those values with those originally supplied by the Producer while generating the values.

When a Consumer receives caching related request headers, it MAY propagate such headers to the Producer either via the clientHeaders structure (for those operations that return markup) or as HTTP request headers for resource generating requests over HTTP.