RE: Conditional GETs?
Hi Peter,
This case is handled a bit differently because we do want to return the
representation's metadata to the client in this case. Currently, the
Response's entity must be an instance of Representation and not a simple
Variant.
Note that the HTTP connectors do recognize the 204 status and won't send the
Representation's content, only the metadata, but it is true that
Resource#getRepresentation(Variant) will be invoked.
Do you have use cases that would help me feel how important it is to
optimize this? As a workaround to returning full representations, you could
write an EmptyRepresentation that would be a Variant with no content. Maybe
that would be a useful addition to the API.
Best regards,
Jerome
-Message d'origine-
De : news [mailto:[EMAIL PROTECTED] De la part de Peter Lacey
Envoyé : mercredi 20 juin 2007 18:26
À : discuss@restlet.tigris.org
Objet : Re: Conditional GETs?
Jerome,
Here's another variant of the same issue. If the server
wants to return
a 204 (No Content), then #getRepresentation() is still
called. Does it
make sense to optimize this out of the way so that the status
can be set
in the constructor and Restlet takes care of doing the right
thing, or
should the status be set by the developer in #getRepresentation() and
null returned?
Pete
Jerome Louvel wrote:
Hi all,
This RFE is now fixed in SVN trunk and will be testable in
the upcoming 1.1
snapshot. Great optimization, thanks Stian for the idea.
Best regards,
Jerome
-Message d'origine-
De : Jerome Louvel [mailto:[EMAIL PROTECTED]
Envoyé : mardi 12 juin 2007 08:55
À : discuss@restlet.tigris.org
Objet : Re: Conditional GETs?
Hi Adam,
There is already a tag property on the Variant class
that you can
already use. In 1.1, we will simply use this property
earlier in the
algorithm to not call getRepresentation(Variant) when not
necessary.
Best regards,
Jerome
Adam Taft a écrit :
By the way, I love the suggestion.
Can't you add getTag() (or some method) sooner rather than
later? The
default implementation would simply return NULL which would
then force
the algorithm to call getRepresentation() just like it
currently does.
There should be no consequence of this in 1.0.x code?
Just curious.
Adam
Jerome Louvel wrote:
Hi Stian,
We haven't forgotten about your suggestion, just dealing
with a long
email
backlog :)
It is perfectly possible to optimize the internal
algorithm so that
getRepresentation(Variant) is never called when the
variant's tag
matches
the one provided by the client.
I've entered a RFE to keep track of it:
http://restlet.tigris.org/issues/show_bug.cgi?id=319
As it changes the observed behavior a bit, it should only go in
Restlet 1.1,
IMHO.
Best regards,
Jerome
-Message d'origine-
De : Stian Soiland [mailto:[EMAIL PROTECTED] Envoyé
: mercredi
6 juin 2007 11:23
À : discuss@restlet.tigris.org
Objet : Re: Conditional GETs?
On 4 Jun 2007, at 15:53, Peter Lacey wrote:
public Representation getRepresentation(Variant variant) {
Representation result = null;
if
(variant.getMediaType().equals(MediaType.APPLICATION_XML)) {
// create DOM
result = new
DomRepresentation(MediaType.APPLICATION_XML,
doc);
result.setTag(new Tag([your etag], false));
}
return result;
}
It's really clever, except you still have to create that XML
representation that never needs to be sent out.
If there was some getTag() method or something you could
override
this to check directly with the database on whatever
you need to
calculate the tag, and hence getRepresentation() wouldn't
even need
to be called.
To support this I think some kind of getLastModified()
would also
be cool. (I've made such a thing in my subclass of Resource)
--
Stian Soiland, myGrid team
School of Computer Science
The University of Manchester
http://www.cs.man.ac.uk/~ssoiland/
Re: Conditional GETs?
Jerome,
Here's another variant of the same issue. If the server wants to return
a 204 (No Content), then #getRepresentation() is still called. Does it
make sense to optimize this out of the way so that the status can be set
in the constructor and Restlet takes care of doing the right thing, or
should the status be set by the developer in #getRepresentation() and
null returned?
Pete
Jerome Louvel wrote:
Hi all,
This RFE is now fixed in SVN trunk and will be testable in the upcoming 1.1
snapshot. Great optimization, thanks Stian for the idea.
Best regards,
Jerome
-Message d'origine-
De : Jerome Louvel [mailto:[EMAIL PROTECTED]
Envoyé : mardi 12 juin 2007 08:55
À : discuss@restlet.tigris.org
Objet : Re: Conditional GETs?
Hi Adam,
There is already a tag property on the Variant class that you can
already use. In 1.1, we will simply use this property earlier in the
algorithm to not call getRepresentation(Variant) when not necessary.
Best regards,
Jerome
Adam Taft a écrit :
By the way, I love the suggestion.
Can't you add getTag() (or some method) sooner rather than
later? The
default implementation would simply return NULL which would
then force
the algorithm to call getRepresentation() just like it
currently does.
There should be no consequence of this in 1.0.x code?
Just curious.
Adam
Jerome Louvel wrote:
Hi Stian,
We haven't forgotten about your suggestion, just dealing
with a long
email
backlog :)
It is perfectly possible to optimize the internal algorithm so that
getRepresentation(Variant) is never called when the variant's tag
matches
the one provided by the client.
I've entered a RFE to keep track of it:
http://restlet.tigris.org/issues/show_bug.cgi?id=319
As it changes the observed behavior a bit, it should only go in
Restlet 1.1,
IMHO.
Best regards,
Jerome
-Message d'origine-
De : Stian Soiland [mailto:[EMAIL PROTECTED] Envoyé
: mercredi
6 juin 2007 11:23
À : discuss@restlet.tigris.org
Objet : Re: Conditional GETs?
On 4 Jun 2007, at 15:53, Peter Lacey wrote:
public Representation getRepresentation(Variant variant) {
Representation result = null;
if
(variant.getMediaType().equals(MediaType.APPLICATION_XML)) {
// create DOM
result = new
DomRepresentation(MediaType.APPLICATION_XML,
doc);
result.setTag(new Tag([your etag], false));
}
return result;
}
It's really clever, except you still have to create that XML
representation that never needs to be sent out.
If there was some getTag() method or something you could
override
this to check directly with the database on whatever you need to
calculate the tag, and hence getRepresentation() wouldn't
even need
to be called.
To support this I think some kind of getLastModified() would also
be cool. (I've made such a thing in my subclass of Resource)
--
Stian Soiland, myGrid team
School of Computer Science
The University of Manchester
http://www.cs.man.ac.uk/~ssoiland/
Re: Conditional GETs?
Jerome, I'm eagerly awaiting this snapshot! No pressure, but are we looking at a matter of days here, or is it more like weeks? Thanks! Avi On 6/16/07, Jerome Louvel [EMAIL PROTECTED] wrote: Hi all, This RFE is now fixed in SVN trunk and will be testable in the upcoming 1.1 snapshot. Great optimization, thanks Stian for the idea. Best regards, Jerome
RE: Conditional GETs?
Hi Avi, A matter of days! Version 1.0.2 is pending too. Best regards, Jerome -Message d'origine- De : Avi Flax [mailto:[EMAIL PROTECTED] Envoyé : lundi 18 juin 2007 20:05 À : discuss@restlet.tigris.org Objet : Re: Conditional GETs? Jerome, I'm eagerly awaiting this snapshot! No pressure, but are we looking at a matter of days here, or is it more like weeks? Thanks! Avi On 6/16/07, Jerome Louvel [EMAIL PROTECTED] wrote: Hi all, This RFE is now fixed in SVN trunk and will be testable in the upcoming 1.1 snapshot. Great optimization, thanks Stian for the idea. Best regards, Jerome
RE: Conditional GETs?
Hi all,
This RFE is now fixed in SVN trunk and will be testable in the upcoming 1.1
snapshot. Great optimization, thanks Stian for the idea.
Best regards,
Jerome
-Message d'origine-
De : Jerome Louvel [mailto:[EMAIL PROTECTED]
Envoyé : mardi 12 juin 2007 08:55
À : discuss@restlet.tigris.org
Objet : Re: Conditional GETs?
Hi Adam,
There is already a tag property on the Variant class that you can
already use. In 1.1, we will simply use this property earlier in the
algorithm to not call getRepresentation(Variant) when not necessary.
Best regards,
Jerome
Adam Taft a écrit :
By the way, I love the suggestion.
Can't you add getTag() (or some method) sooner rather than
later? The
default implementation would simply return NULL which would
then force
the algorithm to call getRepresentation() just like it
currently does.
There should be no consequence of this in 1.0.x code?
Just curious.
Adam
Jerome Louvel wrote:
Hi Stian,
We haven't forgotten about your suggestion, just dealing
with a long
email
backlog :)
It is perfectly possible to optimize the internal algorithm so that
getRepresentation(Variant) is never called when the variant's tag
matches
the one provided by the client.
I've entered a RFE to keep track of it:
http://restlet.tigris.org/issues/show_bug.cgi?id=319
As it changes the observed behavior a bit, it should only go in
Restlet 1.1,
IMHO.
Best regards,
Jerome
-Message d'origine-
De : Stian Soiland [mailto:[EMAIL PROTECTED] Envoyé
: mercredi
6 juin 2007 11:23
À : discuss@restlet.tigris.org
Objet : Re: Conditional GETs?
On 4 Jun 2007, at 15:53, Peter Lacey wrote:
public Representation getRepresentation(Variant variant) {
Representation result = null;
if
(variant.getMediaType().equals(MediaType.APPLICATION_XML)) {
// create DOM
result = new
DomRepresentation(MediaType.APPLICATION_XML,
doc);
result.setTag(new Tag([your etag], false));
}
return result;
}
It's really clever, except you still have to create that XML
representation that never needs to be sent out.
If there was some getTag() method or something you could
override
this to check directly with the database on whatever you need to
calculate the tag, and hence getRepresentation() wouldn't
even need
to be called.
To support this I think some kind of getLastModified() would also
be cool. (I've made such a thing in my subclass of Resource)
--
Stian Soiland, myGrid team
School of Computer Science
The University of Manchester
http://www.cs.man.ac.uk/~ssoiland/
Re: Conditional GETs?
Hi Adam,
There is already a tag property on the Variant class that you can
already use. In 1.1, we will simply use this property earlier in the
algorithm to not call getRepresentation(Variant) when not necessary.
Best regards,
Jerome
Adam Taft a écrit :
By the way, I love the suggestion.
Can't you add getTag() (or some method) sooner rather than later? The
default implementation would simply return NULL which would then force
the algorithm to call getRepresentation() just like it currently does.
There should be no consequence of this in 1.0.x code?
Just curious.
Adam
Jerome Louvel wrote:
Hi Stian,
We haven't forgotten about your suggestion, just dealing with a long
email
backlog :)
It is perfectly possible to optimize the internal algorithm so that
getRepresentation(Variant) is never called when the variant's tag
matches
the one provided by the client.
I've entered a RFE to keep track of it:
http://restlet.tigris.org/issues/show_bug.cgi?id=319
As it changes the observed behavior a bit, it should only go in
Restlet 1.1,
IMHO.
Best regards,
Jerome
-Message d'origine-
De : Stian Soiland [mailto:[EMAIL PROTECTED] Envoyé : mercredi
6 juin 2007 11:23
À : discuss@restlet.tigris.org
Objet : Re: Conditional GETs?
On 4 Jun 2007, at 15:53, Peter Lacey wrote:
public Representation getRepresentation(Variant variant) {
Representation result = null;
if (variant.getMediaType().equals(MediaType.APPLICATION_XML)) {
// create DOM
result = new DomRepresentation(MediaType.APPLICATION_XML,
doc);
result.setTag(new Tag([your etag], false));
}
return result;
}
It's really clever, except you still have to create that XML
representation that never needs to be sent out.
If there was some getTag() method or something you could override
this to check directly with the database on whatever you need to
calculate the tag, and hence getRepresentation() wouldn't even need
to be called.
To support this I think some kind of getLastModified() would also
be cool. (I've made such a thing in my subclass of Resource)
--
Stian Soiland, myGrid team
School of Computer Science
The University of Manchester
http://www.cs.man.ac.uk/~ssoiland/
Re: Conditional GETs?
On 4 Jun 2007, at 15:53, Peter Lacey wrote:
public Representation getRepresentation(Variant variant) {
Representation result = null;
if (variant.getMediaType().equals(MediaType.APPLICATION_XML)) {
// create DOM
result = new DomRepresentation(MediaType.APPLICATION_XML,
doc);
result.setTag(new Tag([your etag], false));
}
return result;
}
It's really clever, except you still have to create that XML
representation that never needs to be sent out.
If there was some getTag() method or something you could override
this to check directly with the database on whatever you need to
calculate the tag, and hence getRepresentation() wouldn't even need
to be called.
To support this I think some kind of getLastModified() would also be
cool. (I've made such a thing in my subclass of Resource)
--
Stian Soiland, myGrid team
School of Computer Science
The University of Manchester
http://www.cs.man.ac.uk/~ssoiland/
Re: Conditional GETs?
Never mind. I figured it out.
For the record. It's enough to just tack the ETag onto the
representation. RESTlet is smart enough to compare it to the client
conditions and send back the 304 and an empty representation for you if
necessary. Cool! I was expecting to have to do a lot more work.
For instance:
public Representation getRepresentation(Variant variant) {
Representation result = null;
if (variant.getMediaType().equals(MediaType.APPLICATION_XML)) {
// create DOM
result = new DomRepresentation(MediaType.APPLICATION_XML, doc);
result.setTag(new Tag([your etag], false));
}
return result;
}
Peter Lacey wrote:
Hi,
I'm new to RESTlet and trying to create a resource that supports
conditional gets (ETag, Not Modied). So far I have the normal GET done,
I can attach an ETag to the representation, I can see how to get the
conditions from the client request, and I can see how to send back a
304. But for the life of me, I can't see how to send back a 304 _and_
the ETag.
To send the ETag I need to call setTag on a Representation. But when
I'm returning a 304, I don't have a Representation per se. I've tried
returning Variants and empty Representations (DomRepresentation in my
case) from my resource's getRepresentation() method, but these attempts
didn't pan out. Nor has anything else I tried.
I would really appreciate it, if someone could explain or provide some
sample code that shows how to do this.
Thanks,
Pete
