July 1999 - Zope - Zope lists

Re: [Zope] Using Zclasses
by Michael Bernstein 06 Jul '99

06 Jul '99

Michel Pelletier wrote: > > Michael Bernstein wrote: > > > > Alexander Staubo wrote: > > > > > > Your second question is trickier, because Zope does not, > > > afaik, support > > > properties that are objects. It's possible, but I believe > > > you can't edit > > > these properties through the standard management > > > interfaces. Instead, > > > you must built your own, and you might have to use Python > > > to store these > > > properties. > > > > Hmm, seems a pretty important feature, does anyone know if > > this sort of > > functionality is on the drawing board for the Zope interface? > > > > Currently, Properties offer the only way to have assignable attributes > in DTML, so it is possible to instanciate an object and assign it to a > property. You would most likely get errors if you tried to manage that > property through the managment interface, but otherwise it would behave > as expected. The sort of thing I want to do, is create a property in a ZClass that will contain a pointer to an instance of some other ZClass of a particular metatype. For example: A Book ZCLass that has an Author property that points to an instance of an Author ZClass. The Author should have ordinary properties taht are accessible as subproperties of the Book instance. So that when displaying the book, I should be able to insert a  and get the expected result. The problem with containing the Author within the Book, is that this does not allow for many-to-many relationships without a lot of redundancy. As I understand it, the chief benefit ODBMSs have over RDBMSs is that expensive SQL joins are replaced by (computationaly speaking)cheap pointer lookups. I really think that ZOPE would benefit from this capability. It would also alleviate the biggest problem I have with the interface which is the constraint to a singly rooted exact heirarchy. Perhaps I'm barking up the wrong tree here. Can ZCatalogs help with this sort of situation? my actual model will probably have over a dozen object types. Michael Bernstein.

1 0

RE: [Zope] Using Zclasses
by Alexander Staubo 06 Jul '99

06 Jul '99

>Alexander Staubo wrote: >> >> To answer your first question, let your "parent" ZClass be a >descendant >> of Object Manager; then define your "child" ZClass _within_ >the parent >> ZClass definition; that is, add the child ZClass as a >subobject of the >> parent. > >I assume that you mean that I should create the 'child' ZClass within >the 'Methods' tab of the parent? Yes, that's how it's supposed to work, odd as it may seem. Never tried this myself, though. >> Your second question is trickier, because Zope does not, >afaik, support >> properties that are objects. It's possible, but I believe >you can't edit >> these properties through the standard management interfaces. Instead, >> you must built your own, and you might have to use Python to >store these >> properties. > >Hmm, seems a pretty important feature, does anyone know if this sort of >functionality is on the drawing board for the Zope interface? Post it to the Collector (http://www.zope.org/Collector) if you think it's important. I agree; but this prompt the question: "Yes, but how?" Should you be able to define properties that can accept only one type of object? Several types? Any type of object? Another aspect is interdependencies -- you might want to introduce deletion constraint on which objects may be deleted if they're referenced, and so on. >> The alternative, of course, is to use a string property and >refer to the >> object's ID. Acquisition will permit you to access any object in the >> hierarchy above the object in question. > >Do you have an example of a simple working application that uses this >technique? Nope, but assuming that document Foo has a string property OtherObject, you can do this(untested):: Other object's id is:  Title of that object is: <br> Result of osme method call: <br> >And what happens when the pointed-to object is deleted or >modified? Nothing, so you should do something like this in the documents that use the contents of the property::    or something like that, assuming HasAttr() is an External Method that tests for the existence of a property (I have not found this functionality in Zope's built-in DTML API: The closest I you get is getattr, which raises an error if it fails). I implement this function like so:: def HasAttr(o, attr): return hasattr(o, attr) -- Alexander Staubo http://www.mop.no/~alex/ "What the hell, he thought, you're only young once, and threw himself out of the window. That would at least keep the element of surprise on his side." --Douglas Adams, _The Hitchhiker's Guide to the Galaxy_

2 1

win32 Zope2
by Robin Becker 06 Jul '99

06 Jul '99

I'm trying out Zope2. I have used the zopewin32 stuff from Anthony Pfrunder and everything seems to build ok. When I run z2.py I get some warnings about Data.fs and in later runs I always see the message FS21 warn: C:\Python\devel\ZOPE/var/Data.fs Database records in the future I then find that I cannot add simple DHTML documents. Although the manage stuff seems mostly to work. I'm constantly getting the error message Zope Error Zope has encountered an error while publishing this resource. exceptions.OverflowError Sorry, a Zope error occurred. although I have managed to add some documents I suspect database corruption. I have also noticed that http://localhost:9673/manage_propertiesForm is accessible without logging in is this normal? Any help appreciated. -- Robin Becker

2 2

RE: [Zope] semipersistent
by Michel Pelletier 06 Jul '99

06 Jul '99

> -----Original Message----- > From: Robin Becker [mailto:robin@jessikat.demon.co.uk] > Sent: Tuesday, July 06, 1999 12:01 PM > To: zope(a)zope.org > Subject: [Zope] semipersistent > > > I'm using various external methods to create GIF files in my current > server. These are expensive to produce, but are created on a per user > basis eg as the results of a user input. > > How can I make these temporary in the sense that they live until the > connection is dropped. Hmm.. I wonder what you mean by 'connection is dropped'? HTTP connections are stateless and immediately drop themselves upon completion. Do you mean to cache the images? This would require writing your own Product with some trickery. Also, it would be possible to write your own user folder which handled a 'session' and associated a certain object store (whether persistent or not) that lasted in memory as long as your session lasted. This also would require some python. -Michel > -- > Robin Becker > > _______________________________________________ > Zope maillist - Zope(a)zope.org > http://www.zope.org/mailman/listinfo/zope > > (For developer-specific issues, use the companion list, > zope-dev(a)zope.org - http://www.zope.org/mailman/listinfo/zope-dev ) >

2 1

RE: [Zope]  statement starting from "root" folder
by Perez, Victor 06 Jul '99

06 Jul '99

Thanks, works fine now. Is somewhere a good reference on all this stuff? (the PARENTS thing doesn't appear anywhere in the zope docs, at least the ones I've reading) - Atentamente, Victor Perez Muena Automation Support - Port Area (Los Vilos) Los Pelambres Project - Bechtel Chile Ltda. Ext. 8033, Phone: (2) 361-8033 - Fax: (2) 361-8025 > -----Original Message----- > From: Alexander Staubo [SMTP:alex@mop.no] > Sent: Friday, July 02, 1999 12:56 AM > To: Zope Mailing List (E-mail) > Subject: RE: [Zope]  statement starting from "root" folder > > Try: > >  > > PARENTS[-1] gives you the topmost parent. PARENTS[0] gives you the most > immediate parent. > > -- > Alexander Staubo http://www.mop.no/~alex/ > "`This must be Thursday,' said Arthur to himself, sinking low over > his beer, `I never could get the hang of Thursdays.'" > --Douglas Adams, _The Hitchhiker's Guide to the Galaxy_ > > >-----Original Message----- > >From: zope-admin(a)zope.org [mailto:zope-admin@zope.org]On Behalf Of > >Perez, Victor > >Sent: 1. juli 1999 20:00 > >To: 'zope' > >Subject: [Zope]  statement starting from "root" folder > > > > > >Hi zoppers: > > > >First of all, I just started working on zope so I apologize if > >this question > >if too obvious for you, but I didn't find the answer on the docs.... > > > >I'm trying to make a navigation section on the left of my > >pages, something > >pretty near to the  statement, but I don't want the "plus" > >signs, so I decided to work with  statements based > >on a example > >I've found on the Zbook doc (zb_all_view). > > > >My "navigation" DTML starts with  and I want it to always start > >from the "root" > >folder, showing only the subfolders for the branch I'm inside. > > > >Any help is welcomed. > > > >- > >Atentamente, > >Victor Perez Muena > >Automation Support - Port Area (Los Vilos) > >Los Pelambres Project - Bechtel Chile Ltda. > >Ext. 8033, Phone: (2) 361-8033 - Fax: (2) 361-8025 > > > > > >_______________________________________________ > >Zope maillist - Zope(a)zope.org > >http://www.zope.org/mailman/listinfo/zope > > > >(For developer-specific issues, use the companion list, > >zope-dev(a)zope.org - http://www.zope.org/mailman/listinfo/zope-dev ) > > > > > _______________________________________________ > Zope maillist - Zope(a)zope.org > http://www.zope.org/mailman/listinfo/zope > > (For developer-specific issues, use the companion list, > zope-dev(a)zope.org - http://www.zope.org/mailman/listinfo/zope-dev )

2 1

zope with apache 1.3 (from RedHat 6.0)
by Perez, Victor 06 Jul '99

06 Jul '99

Could somebody make zope works with the apache from RedHat 6.0? If so, please let me know how, since I tried everything and can't make it pass authentification information to zope. - Atentamente, Victor Perez Muena Automation Support - Port Area (Los Vilos) Los Pelambres Project - Bechtel Chile Ltda. Ext. 8033, Phone: (2) 361-8033 - Fax: (2) 361-8025

2 1

Running Zope with Apache
by Jeff Clement 06 Jul '99

06 Jul '99

Is there any good documentation on making Zope run with Apache? I've added the rewrite lines to the .htaccess in my directory. Whenever I run Zope.cgi from commandline I get error (102) failure during connect. And running from the server givew error 500. Thanks, Jeff 7/6/99 12:35:34 PM [ Jeff Clement / BlueSine Consulting] email: jeff(a)bluesine.tj web: www.bluesine.tj cell: 403.850.9180

1 0

Perl Benchmarks - how about a Zope comparision?
by Itamar S.-T. 06 Jul '99

06 Jul '99

http://perl.pattern.net/bench/ Anyone willing to run a Zope test on top of Apache for comparision?

1 0

calling a Python module from Zope
by Wolfgang Stroh 06 Jul '99

06 Jul '99

Hello! After reading all available documentation I wonder how to call a .py file from Zope. In which path is it expected? I've installed ZPyGreSQLDA and the connection to the database is working. A simple query with ZSQL Method works. Now I would like to execute the .py files in Zope-1.10.2-src/lib/python/Products/ZPyGreSQLDA/src/tutorial e.g. to list the system catalog. What can I do? Thank's for any help! Wolfgang

1 0

RE: [Zope] Using Zclasses
by Michel Pelletier 06 Jul '99

06 Jul '99

> -----Original Message----- > From: Martijn Pieters [mailto:mj@antraciet.nl] > Sent: Tuesday, July 06, 1999 8:44 AM > To: Michel Pelletier; Zope Mailing List (E-mail) > Subject: RE: [Zope] Using Zclasses > > > At 14:22 06/07/99 , Michel Pelletier wrote: > >The _ namespace has a hasattr. Quote DocumentTemplate/DT_Util.py: > > > > This variable also has attributes that provide access to standard > > utility objects. These attributes include: > > > > - The objects: 'None', 'abs', 'chr', 'divmod', 'float', 'hash', > > 'hex', 'int', 'len', 'max', 'min', 'oct', 'ord', 'pow', > > 'round', and 'str' from the standard Python builtin module. > > So the 'range' method is absent in the documentation. Uhmm.. well it's absent in the *souce code* but it is documented! doc/CREDITS.txt: o Martijn Pieters chipped in with a safe range function. ;) -Michel > > -- > Martijn Pieters, Web Developer > | Antraciet http://www.antraciet.nl > | Tel: +31-35-7502100 Fax: +31-35-7502111 > | mailto:mj@antraciet.nl http://www.antraciet.nl/~mj > | PGP: > http://wwwkeys.nl.pgp.net:11371/pks/lookup?op=get&search=0xA8A32149 > ------------------------------------------ > > _______________________________________________ > Zope maillist - Zope(a)zope.org > http://www.zope.org/mailman/listinfo/zope > > (For developer-specific issues, use the companion list, > zope-dev(a)zope.org - http://www.zope.org/mailman/listinfo/zope-dev ) >

1 0