September 2000 - Zope-Dev

HiperDOM & xmlc
by Spicklemire, Jerry 19 Sep '00

19 Sep '00

There are a few things I'm trying to understand about the xmlc-like Templates proposal. First : "Using specialized webdesigners with Zope project has been one of the biggest pains in Zope development; we have to take the sometimes ugly code generated by the tools they use, usually clean it up, then insert the DTML tags in it. Making changes to the design is a nightmare." http://lists.zope.org/pipermail/zope-dev/2000-September/006893.html 'Yep. Essentially the programmers "steal" the presentation/view layer from the designers and convert it to "code".' http://lists.zope.org/pipermail/zope-dev/2000-September/006958.html OK, point taken, but it's not quite that simple. In the end, isn't that why artist do design, and coders code? One of the primary purposes in a complete Content Management System is to distill the presentation standard in a way that can be "layered" over any content. This principle doesn't stop at a clearly delineated "visual" line. Leaving the page layout "as is", which is what it sounds like you are suggesting, is even worse than doing the job right at the "cast into code" stage. If you leave the ugly HTML ugly, it will still be ugly next time it gets updated, but it will be much less useful in the meantime. Worse, it's likely to get uglier over time. Have you ever seen a baby rhinocerous? To me the real solution is to clean up the layout, converting hard coded "virtual" lists into real lists, etc., while painstakingly preserving the visual design. That clean, codified version can then be leveraged to the utmost during it's production life, and still be fed back to the designer at design update time. This can be easily done today in the form of a static HTML file, simply by calling the Zope URL of the base template, and hitting "save as". With the proposed xmlc-ish Template, the "snapshot" step should not be needed, which is great! Granted, if the person who distills the design into clean, reusable HTML / DTML / XML hasn't done the job well, incorporating the changes of the updated version may well be a nightmare. On the other hand, if this crucial step is done well, adapting the base template to match the "new vision" should in fact be much easier the second time. I think a large part of the confusion comes from where we each draw the conceptual line regarding what is "visual" and what is best handled as "code". An anchor tag is, after all, just a pointer to some related stuff, not the actual physical location of anything. If making it easy for visual folks to avoid this basic fact is the driver here, there's a much larger problem looming in the immediate XML future . . . Also, the idea of presenting a place holder sounds a lot like : "As for cases where a dataset is displayed, such as by a ZSQL query, perhaps a single "dummy" row, or cell, could stand in for design purposes." http://www.zope.org/Resources/Mozilla/ZWiki/IDEs Is that what you mean? Is the "dummy" stuff intended to resemble the final content, or just to mark an insertion point? Might it be possible to make place holders in the form of anchors (links) to DTML Methods, or other appropriate forms of native Zope elements, so that DreamWeaver, et. al. can pull down a "real" item, rather than having a hard coded "stuff goes here" label? That sounds advantageous to me, in terms of validating a visual design. Groping toward grokking, Jerry S.

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Re: ZPatterns (sub-)transaction problems
by Steve Alexander 19 Sep '00

19 Sep '00

"Phillip J. Eby" wrote: > > I will try to have a ZPatterns snapshot release made this week that will > include those fixes (plus the fix for a problem with DynPersist that we > also discovered yesterday). Great. I'm looking forward to that. Can we lose DynPersist altogether for this release? Or are there still folks out there using ZPatterns with 2.1.6? -- Steve Alexander Software Engineer Cat-Box limited http://www.cat-box.net

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ZPatterns bug: infinite recursion with External Attribute Provider
by Steve Alexander 19 Sep '00

19 Sep '00

ZPatterns-0-4-2a2 When I use an External Attribute Provider, I get an infinite recursion problem, and Zope hangs. This is because DataManager (in DataManagers.py) uses normal getattr() and object.__skinSlot__ methods to get and set the special attribute __skinSlot__ on DataSkins. Thus, the system tries to store the __skinSlot__ attribute in the DataSkin instance by storing the __skinSlot__ attribute in the DataSkin instance by storing the __skinSlot__ attribute in the DataSkin instance by... I can fix this, by patching DataManager to use client.__dict__ instead: def _readableSlotFor(self,client): #slot = getattr(client,'__skinSlot__',_marker) slot = client.__dict__.get('__skinSlot__',_marker) if slot is _marker: return {} client._setSlot(slot); return slot def _writeableSlotFor(self,client): #slot = getattr(client,'__skinSlot__',_marker) slot = client.__dict__.get('__skinSlot__',_marker) if slot is _marker: #slot = client.__skinSlot__ = PersistentMapping() slot = client.__dict__['__skinSlot__'] = PersistentMapping() client._setSlot(slot); return slot This works, in as far as I can do things like add sub-objects to a ZClass that derives from DataSkin and ObjectManager without infinite regress. However, I still get an attribute error. This is because the External Attribute Provider only offers to set and delete its attributes. I'm confused as to why this should be -- surely the External Attribute Provider should offer to get the same attributes as it is offering to set and delete? Or, do I have to use an extra provider in the form of some SkinScript or a Generic Attribute Provider to do the getting? I tried altering namesForRegistration, so that the External Attribute Provider would offer to getattr for "*", then refreshed the customizer I'd put the EAP into. def namesForRegistration(self,container): """XXX""" return { 'provides':('attributes',), 'setattr': self.Attributes, 'delattr': self.Attributes, 'getattr': self.Attributes } I can now add sub-objects to my ZClass instances, and I can traverse to those sub-objects by typing them into the URL field of my browser. However, I can't get a list of the sub-objects by calling objectIds. I'm trying to make sense of External Attribute Provider so that I can write a BTreeAttributeProvider for DataSkinAddons, as discussed on the zope-dev list at the end of August, subject "BTreeFolder /w Customizer support". Any pointers appreciated. -- Steve Alexander Software Engineer Cat-Box limited http://www.cat-box.net

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Using PropertySheets
by Erich Seifert 19 Sep '00

19 Sep '00

Hi everbody, I've played a bit with the PropertySheets interface and I wanted to create two Stylesheets. Everything works fine, but ... * I don't get the management tabs in the propertysheet/manage method. Perhaps a permission problem? * I can't pass a default value to a tokens property. How to? * I can't pass a default value to a boolean property. How to? Could someone please give me some example code or hints? Thanks in advance Eric

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Returning a list of names from a Python Method
by Michael Bernstein 19 Sep '00

19 Sep '00

Bill Anderson wrote: > > Michael Bernstein wrote: > > > > I *think* I've created a getUserNames python method that returns the > > appropriate results: > > > > Parameter list: > > self > > > > Body: > > > > user_ids=self.UserSource.getPersistentItemIDs() > > > > names=[] > > for i in user_ids: > > names.append(self.getItem(i)) > > return names > > Returns a list of objects. > > > I don't understand the differences between the code I pasted above and > > the code on the original getUserNames method (from : > > > > def getUserNames(self): > > """Return a list of usernames""" > > names=self.data.keys() > > names.sort() > > return names > > Returns a list of usernames. > > > Can anyone tell me what I need to fix? > > Unfortunately, I cannot yet. Does anyone on the list know how to change the getUserNames Python method to return a list of names instead of a list of objects? The code in question is this: user_ids=self.UserSource.getPersistentItemIDs() names=[] for i in user_ids: names.append(self.getItem(i)) return names Thanks, Michael Bernstein

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__del__
by Andy McKay 18 Sep '00

18 Sep '00

Is there an method that I can use as a hook when an object is destroyed? (Im trying to save some _v_ data prior to destruction. Ive tried __del__ but this doesnt seem to get called. Thanks. -- Andy McKay, Developer. ActiveState.

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Re: [Zope-dev] Custom dtml tag
by Brett Carter 18 Sep '00

18 Sep '00

Andy - looking up 'this' in a dtml method or document won't work unless you expose it in your python product/tag definition. I'm talking about getting 'this' inside a dtml tag that I have defined myself (i.e. <dtml-foobar></dtml-foobar>). If you want 'this' available in dtml, write an external method and just return 'self' def this(self): return self -Brett >>>>> "Andy" == Andy McKay <andym(a)activestate.com> writes: Andy> Really? Ive looked up this and get nothing (an attribute error actually) and Andy> its not in globals. If that would work that would be great - but a it Andy> certainly doesnt seem to on a standard DTMLDocument / Method. Andy> ----- Original Message ----- Andy> From: "Brett Carter" <brett(a)kavi.com> Andy> To: "Andy McKay" <andym(a)activestate.com> Andy> Cc: <zope-dev(a)zope.org> Andy> Sent: Tuesday, September 12, 2000 4:17 PM Andy> Subject: Re: [Zope-dev] Custom dtml tag >> Andy: here's what I've gleaned - in a dtml tag's render() method, you >> get passed in self and a template dict, in my example let's call it >> 'md'. md is essentially a stack/dictionaryish object of the *current* >> namespace - and one of the handy things that's always around in the >> namespace is the 'this' function, which returns the object on the top >> of the stack. >> >> Just lookup 'this', run it, and there you have a reference to the >> calling object! Ex: >> >> def render(self, md) >> this = md.getitem('this') >> callingObj = this() >> return "Calling object was %s" % (callingObj.id()) >> >> Note I haven't tested this code. Good luck! >> -Brett >>

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soap and zope
by Magnus Heino (Rivermen) 18 Sep '00

18 Sep '00

Has anyone done anything with soap and zope? /Magnus Heino

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Adding functions to _
by Itamar Shtull-Trauring 18 Sep '00

18 Sep '00

I'm using CVS Zope, and I want to add a function of mine to _, so I have the following code in a Product's __init__.py: from log2vis import log2vis from DocumentTemplate.DT_Util import d d["log2vis"] = log2vis However, when I call the function, I get an error about DocumentTemplate, from which I discovered that when I call _.logvis('a_string'), instead of the string being passed as the first parameter, _ is passed as the first parameter to my function, forcing me to truncate it when calling log2vis: from log2vis import log2vis from DocumentTemplate.DT_Util import d def log2vis_wrapper(*args, **kwargs): return apply(log2vis, args[1:], kwargs) d["log2vis"] = log2vis_wrapper Any idea what could cause this strange behaviour? it doesn't happen for other functions inserted into _ in DT_Util.py. -- Itamar S.T. itamar(a)maxnm.com Fingerprint = D365 7BE8 B81E 2B18 6534 025E D0E7 92DB E441 411C

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Calendar tag 0.9.22 released
by al028823＠alumail.uji.es 18 Sep '00

18 Sep '00

Hi all, There's a new version of the calendar tag, I need feedback about it, specially from those who use the "setCalendar('url_', ...)" hook or the "linkDate(...)" function. thanks, david

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