October 1999 - Zope - Zope lists

RE: [Zope] Need help trying to add objects to a Object Manager ZC lass
by Jay, Dylan 13 Oct '99

13 Oct '99

> -----Original Message----- > From: Stuart 'Zen' Bishop [mailto:zen@cs.rmit.edu.au] > Sent: Wednesday, October 13, 1999 21:09 > To: Jay, Dylan > Cc: zope(a)zope.org > Subject: RE: [Zope] Need help trying to add objects to a > Object Manager > ZC lass > > > On Wed, 13 Oct 1999, Jay, Dylan wrote: > > > > You need to inherit from Folder as well. > > > This one bit me last week. :-| > > > > This doesn't work. Can anyone tell me why this might be > happening????? I'm > > really starting to think ZClasses are just a complete waste of time. > > I think what is happening is the following: > Some objects think of themselves as 'methods'. If you ask them for > this(), they will report their container object. > > Other objects, like folder, report themselves when asked > for this(). > > If you are inheriting from multiple baseclasses, the order will be > significant. Try making folder the first object in the list > you inherit from. If this doesn't work, try making it the last > (I don't know if the top of the list or the bottom will > take precedance). I have yet to try this however isn't there a conflict here between ZCatalogAware. I thought that ZCatalogAware had to be the first to be inherited?

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REVIEW: "How-To: Z Class Properties"
by Loren Stafford 13 Oct '99

13 Oct '99

I've collected some more information on managing properties in Z Classes into a "How-To" at http://www.zope.org/Members/lstaffor/zProperties. Before I have it registered as an official "How-To", please check it out and make sure that it is accurate and helpful. In particular, I've make some blanket statements positioning Z Classes and Properties within the general field of O-O programming. I'm no expert on O-O, so I might be a little off-base. Please help keep me from leading others astray with inaccurate statements. -- Thanks -- Loren

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Infinite recursion in Document Template
by David C. Morrill 13 Oct '99

13 Oct '99

Can someone explain to me why the following causes an "Infinite Recursion in Document Template" error? <dtml-in "PARENTS[0].objectValues(['DTML Document','DTML Method'])"> <dtml-with sequence-item only> </dtml-with> </dtml-in> Dave Morrill

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Global Product Configuration and GUIs
by Johan Carlsson 13 Oct '99

13 Oct '99

Hi, (With products I mean Python products not ZClass products) I have been thinking about how one can use global product configuration properties, to make dynamic products (but on a global level). Using a configuration file in the Products/product directory would be one way to do it. But I really would like to put configuration forms in the Control Panel/Products/product area and/or save configuration properties as objects/object-properties instead of conf. file. Anyone have suggestions how to do this? Regards, //johan torped johan carlsson birkagatan 9 113 36 stockholm telefon 08-32 31 23 mobil 070-558 25 24 fax 08-32 89 47 johanc(a)torped.se

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Re: [Zope] Linux.com community ad
by Tres Seaver 13 Oct '99

13 Oct '99

Zope -- the Zen of the Web -- ================================================================================ Tres Seaver tseaver(a)palladion.com http://www.palladion.com Palladion Software Houston, Texas, USA 713-523-6582

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RE: [Zope] zope vs. siteserver from ms.siteserver newsgroup
by dale w lance 13 Oct '99

13 Oct '99

> -----Original Message----- > From: Brian [mailto:Brian@digicool.com] > Sent: Wednesday, October 13, 1999 11:42 AM > To: chris; zope > Cc: Brian > Subject: RE: [Zope] zope vs. siteserver from ms.siteserver newsgroup > > > > Here's an exchange I had with a guy in the MS Site Server > > general Usenet > > Newsgroup... can anyone find exception with his or my arguments? > > Additionally, he doubts the ability of Zope to handle large > > sites (near the > > end of the message). Any clarifications are appreciated.... > > > > > > On the opposite, ZOPE is interpreted, not only the > > templates, even the > > > server itself. No paradigm like COM is part of the game > > (though it might > > > be extended). So ZOPE will be less speedy. > > COM happens to work just fine with Zope :^) I've written a > demo ExchangeFolder before that let you march into the > Public Folders on your Exchange server as a little test too > see if it would work. To me, the whole argument of "COM > components are compiled, so they'll be faster" is sort of > a lark anyway. > > If you wanted to, you could crank up your copy of VC++ and > crank out a COM component for your business logic. The fact > that people don't seem to be doing this (or even clamoring > for info on how to do this) is telling. From the point > of view of a web developer, the issue is not "gee, how many > milliseconds faster can this COM component execute my query", > its "how fast can we get this project done". Some people seem > inexplicably not to have caught on to that yet :^) > > > > > > > > Also: I really doubt the scalability of the ZOPE Object database, > > > compared to the SQL Server that is part of the site server > > licensing. > > > The ZOPE Object database - well - there are no benchmarks on it. > > There are no benchmarks, true. It might be worth noting, though, > that the actual backing storage of the object db is pluggable, > documented and extensible. This architecture is specifically > designed to allow the use of alternate backing stores (oracle, > other enterprise dbs, etc.) -- including SQL Server if you were > so inclined. > > > > > "When you do this, you're basically extending the Zope > > environment by > > > creating your own object types without having to know a high-level > > > programming language (ala C++/Visual Basic COM object > > development)." - > > > well, just you do it in a slow interpredet language, where C++ COM > > > Objects will be speedy! > > Yep, speedy as hell - and a year late ;^) See above. > > > > > "The power of this model is formidable. For example, I > developed a > > > "news item" object in 22 minutes which allows my users to > add "news > > > items" to their department for perusal by other department > > members." - > > > nive. What about adding 100.000 news items. What is the > performance > > > then? This is unrealistic? OK, lets make an interface for a > > news server. > > > 1 million messages a day. Youre dead. > > This seems a simpleminded argument. If you are going to do > something like a news server interface, you are also going > to do the obvious design work beforehand that takes scale > risks into account. I believe he entirely missed the most > important points of your statement - "22 minutes", the > implied department-level scope of your solution, and the > fact that it worked for you. > > The "youre dead" bit makes me wonder whether it's really worth > much time bothering with this guy - you can't really answer > someone who obviously already knows all the answers :^) > <RANT> I guess he also misses the point that every time the other operating system (read MS) people come out with a new version it requires a much larger, more powerful machine? </RANT> The idea is to make tools that get software to market faster and better. Zope handles COM (see other replies). Zope interfaces to his database. The only thing left is the Zope development paradigm vs his. Of course this argument has gone on since the 60s and 70s. There has been no luck convincing the other side, but here we are with bigger, faster computers to run interpreted languages (among other things like megalithic office productivity suites etc) Dale Lance

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RE: [Zope] Newbie: need a simple example of external method
by Hung Jung Lu 13 Oct '99

13 Oct '99

Wow, thanks everyone. (Loren, too.) This was much faster than wading through the tons of help files. At some point we should make some document with searchable index to help people finding this kind of information faster. Right now the documentation is a little bit all over places and hard to use. .......... I have noticed that the external methods are only single-level deep. That is, they have one-word names, e.g: myMethod. This might be a problem in large-scale projects, where it is easy to run into name conflicts. Does anyone know whether internally zope uses the "import myModule" and then internally assembles the "myModule.myMethod()" call, or does it use "from myModule import myFunction"? I mean, has any zope users used method calls like myObject.myInnerObject.myFurtherInnerObject.myMethod()? I guess it's ok for Zope to use "from ... import ..." instead of "import ...". It's just that I am very afraid of name collisions. regards, Hung Jung -----Original Message----- From: Pavlos Christoforou [mailto:pavlos@gaaros.msrc.sunysb.edu] Sent: Wednesday, October 13, 1999 1:57 PM To: Hung Jung Lu Cc: 'zope(a)zope.org' Subject: Re: [Zope] Newbie: need a simple example of external method Welcome - On Wed, 13 Oct 1999, Hung Jung Lu wrote: > > myprogram.py: > > def myfunc(x): > return 2*x; > > How do I proceed to use it in DTML, and how do I > place it in the external methods folder? First go in your Zope management screen and select external method from the available object list. Add an id (lets say testit) add the function name (in your case myfunc) and then the python module file (which should exist in the Extensions directory in the main python distribution. In your case myprogram.py) click add and that's about it. In a DTML method you can call your function by simply calling: <dtml-var "testit(3)"> should print out 6 Pavlos

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ZODB Caching and XML Document
by Rahul Dave 13 Oct '99

13 Oct '99

Hi, I'm implementing a site which as a mix of html and Docbook XML documents. I looked at the XML Document Product and liked the philosophy. The way I understand it, a DOM tree is created at document checkin time and stored in the object database. When a request comes in for some method on the tree, it is retrieved from the database and displayed, etc. ZODB has a cache. On such a DOM tree request, what exactly is cached. Is it the entire DOM tree object. If so how can I control the individual caching of the object(can I do that). Having to pull a large DOM tree out of the ZODB will hurt in time I would think(any benchmarks?) and having that tree available in memory would be great. Also, are results of methods on the DOM tree cached. So If the client requests to display node6 and all under it, will the results os the method implementing the request be cached? In general, can a particulay python data structure be marked with some cache properties. I would like to use 4DOM/4XSLT later so I can provide PDF hardcopy for the online documents on a section/by section basis (a "print basket" if you may) Thanks, Rahul

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Calling an python method from within a python method
by Dan Rusch 13 Oct '99

13 Oct '99

Zopesters, Does anyone know if it is possible to call an internal python method (built with the Python Method object) from within an internal python method (also built with the Python Method object)? For example: I have an internal python method called convertDate built with the Python Method object. Inside this method I would like to call another internal python method called isLeapYear(). Can this be done, if so how? Thanks, DR

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Newbie: need a simple example of external method
by Hung Jung Lu 13 Oct '99

13 Oct '99

Hi, I just subscribed to the mailing list, and in less than one day I got 60 messages, wow! This list surely is active. Can anyone give to me a simple example of a DTML document calling an external method? I mean, if I have a Python program myprogram.py: def myfunc(x): return 2*x; How do I proceed to use it in DTML, and how do I place it in the external methods folder? regards, Hung Jung

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