VA801 - Seaside - beginners questions

[marten]

I start with a new development image
Load the Seaside core 8.0.1 into my image
Open the Server Control Panel, create a WASstServerAdaptor and start it
Open at browser at localhost:8080
select "config" and get a new rendered www-page and whatever I do there: I get an error "a ContextEmulator ... arg1 = "" not found while capturing continuation"

Why ????

[marten]

As a beginner in Seaside I must say, that this is pretty hard work .... at least in VASmalltalk. Instantiations refers to the online book of Seaside to get more information about it - but working with the examples in this book one does not come pretty much.

WAPartialContinuation>>captureFrom:to:

seems to fail all the times. When it is used ? Well, when executing "self request:'Name'", which is pretty often used in all these examples.

Another problem (in the same area) is "aWAPartialContinuation value: anArg" fails, because value: is NOT impemented ....

[marten]

And when someone loads the Seaside-Tests feature, one gets an exception "WAAttributeNotFound"

[klaus]

Hi Marten,

I always load all the Seaside stuff, we need, in a fresh image. A reload is not possible and results in this WAAttributeNotFound error.

And when someone loads the Seaside-Tests feature, one gets an exception "WAAttributeNotFound"

See also here http://www.instantiations.com/forum/viewtopic.php?f=12&t=4319&p=14011&hilit=WAAttributeNotFound#p14011

Continuations are not working. My greatest problem isn't still solved http://www.instantiations.com/forum/viewtopic.php?f=12&t=4730 I'll try to solve it, when I have enough time for that.

Regards

Klaus

[jtuchel]

Marten,

And when someone loads the Seaside-Tests feature, one gets an exception "WAAttributeNotFound"

this is caused by a Seaside-Method. IT's not to blame on Instantiations.
Dig for the place where the error happens and look at the method comment. I hope this strange idea will go away in Seaside 3.0, because I see no real benefit in this...

This doesn't mean that I wouldn't love to see fixes from Instantiations come out more frequently. Seaside alpha 5 is quite old now, but the question then is: what kind of snapshot of seaside should they use? There's no new "official" snapshot yet, neither an alpha 6 nor the beta 1, which once was scheduled for August/September 2009...

cu

Joachim

[jtuchel]

I start with a new development image

select "config" and get a new rendered www-page and whatever I do there: I get an error "a ContextEmulator ... arg1 = "" not found while capturing continuation"

Why ????

Marten,

here's what Julian Fitzell said (back in December) about this in a comment to a blog post where I mention this very problem(http://joachimtuchel.wordpress.com/2009 ... plication/) :

You are right… none of the included tools are supposed to be relying on continuations any more. Those usages in the configuration app crept back in, but I think they’ve been fixed in the Seaside repository.

So it's a known bug that has been fixed in Pharo more than 2 months ago.
But you can get around it by configuring the application using the halos after starting the application.
And, of course, you can configure the application in code rather than using the config application.

This seems to be another problem that underlines my wish for more frequent Seaside updates from Instantiations. There are things that have been fixed quite a while ago by the Seaside team, but have not found their way to VAST.

Maybe it's time for a new development build?

cu

Joachim

[marten]

Well updating Seaside on a more frequent base might not be a solution - most of us will loose the overview, what fixes are included, what is working, what is NOT working.

Seaside is part of this product and then one should throw away all stuff, which is NOT working in this product. Or at least one should make clear in the documentation, what is working and what not (and if you are new to the stuff it might not help to say: tasks and continuations) - perhaps adding "self halt" statement in the code and remarks how to change ones programming style might be more useful here.

Summary for me: the online book (I bought it !) for Seaside is nice, but actually one does not really know, if the nice short code examples are running under VASmalltalk and then documentation for Seaside is pretty missing.

How about packaging in headless servers ????

[jtuchel]

Well updating Seaside on a more frequent base might not be a solution - most of us will loose the overview, what fixes are included, what is working, what is NOT working.

Maybe, but we'd probably see some progress. Just remember, Seaside is not in the hands of any vendor, The overview could only come from a link to a place where you can find all solved issues in Seaside itself.
Sure, if Instantiations added a fix to their base code, they could/should provide additional info here.
I guess the Pharo users suffer from a very similar transparency problem.

Seaside is part of this product and then one should throw away all stuff, which is NOT working in this product. Or at least one should make clear in the documentation, what is working and what not (and if you are new to the stuff it might not help to say: tasks and continuations) - perhaps adding "self halt" statement in the code and remarks how to change ones programming style might be more useful here.

I guess the big decision to make here is whether you try to offer as much of Seaside as possible as soon as possible as opposed to waiting for a final 3.0 and providing good documentation for it. You'll always find situations in which there is no easy answer to the question. I like the fact that Seaside is there, and I accept finding problems to some degree, since the Seaside Code is in ALPHA stadium.
Can we blame Instantiations for this? No.
Can we blame Instantiations for not stayng in pace with alpha5?
Well, I think we can, but we need to be prepared for situations in which we find new and old problems and need to rewrite our code several times if we use incremental updates.

Summary for me: the online book (I bought it !) for Seaside is nice, but actually one does not really know, if the nice short code examples are running under VASmalltalk and then documentation for Seaside is pretty missing.

I also bought it (and have read it before) and I must say I get along quite nicely. I would expect a few more explanations of concepts that do not use Continuations since Seaside 3.0 is all about modularization and making Continuations optional, but well...

How about packaging in headless servers ????

I can't answer this one. I 've only deployed dev images to test servers so far.

Joachim

[benvandijk]

I start with a new development image
Load the Seaside core 8.0.1 into my image
Open the Server Control Panel, create a WASstServerAdaptor and start it
Open at browser at localhost:8080
select "config" and get a new rendered www-page and whatever I do there: I get an error "a ContextEmulator ... arg1 = "" not found while capturing continuation"

Why ????

I changed the configure: method in class WAConfigurationBrowser to do a show: instead of a call:.
Not sure if it is the correct solution, but it does the trick

Code: Select all

configure: aHandler
   self selection: aHandler.
   self editor home.
   (self editor activeComponent isKindOf: WADispatcherEmptyPage)
      ifFalse: [self setEmptyPage].
   ^self show: aHandler configurationComponent.

We are currently running headless images on VA 8.0.0, we did not yet try on 8.01.

[jtuchel]

Hi Ben,

looks like a perfect solution to me, since these two are equivalent (apart from the fact that show: doesn't waste as much resources by creating contuations).
I never bothered looking deeper into this because I was expecting a Seaside 3.0 beta "any time soon" and considered this a temporary problem.
Now that Beta 1 is almost 5 months behind its initial schedule, and no alphas coming out, we need to get along with fixing stuff ourselves, obviously.

Well, at least it's educative

[wembley]

Joachim -

Seaside 3.0b1 should be soon (but I have no real control over that).

Meanwhile, we are just wrapping up the first VAST 8.0.2 public development build. This will include all Seaside changes through last Wednesday and 'official' support for method Pragmas (needed for porting Pier) to replace the 'unofficial' support that was included in the Pier port on VAStGoodies.

[jtuchel]

John,

Meanwhile, we are just wrapping up the first VAST 8.0.2 public development build. This will include all Seaside changes through last Wednesday and ...

That's definitely good news. This will hopefully make the overall experience with Seaside in VAST much smoother.

And, of course, we're eager to see Beta 1 become a Reality, so that we can do "real" development on a mostly finalized Framework...

Joachim