July 2000 - Zope-Dev

RE: [Zope-dev] 'issubclass' and 'isinstance' on ExtensionClasses
by Chris McDonough 05 Jul '00

05 Jul '00

According to Andrew Kuchling's and Moshe Zadka's "Python 2.0 what's new list", isinstance() and issubclass() already works on ExtensionClass-based stuff in Python 1.6. See http://starship.python.net/crew/amk/python/writing/new-python/new-python .html#SECTION000900000000000000000 That said, as for right now, I'm not sure if your extended functions do the right thing. Maybe someone else can comment. > -----Original Message----- > From: Greg Ward [mailto:gward@mems-exchange.org] > Sent: Wednesday, July 05, 2000 2:40 PM > To: zope-dev(a)zope.org > Subject: [Zope-dev] 'issubclass' and 'isinstance' on ExtensionClasses > > > Hi all -- > > surely I'm not the first to deal with this: I use > 'isinstance()' a lot, > and 'issubclass()' occasionally, for run-time type-checking. This > breaks when using ZODB Persistent classes, or any other type of > ExtensionClass for that matter. > > I see no use of 'issubclass()' in the Zope lib/python directory, and > only a few scattered uses of 'isinstance()'. (Checked both 2.1.5 and > 2.2b2.) So maybe I *am* the first to worry about this. I'm surprised > that ExtensionClass doesn't include enhanced versions of > 'issubclass()' > and 'isinstance()', though. > > So, here are my versions. Critiques welcome. In particular, is > "type(X) is not ClassType and hasattr(X, '__bases__')" an adequate > determination that X is indeed an extension class? > > If you folks want to include these with ExtensionClass (possibly with > the leading "ec_" trimmed from the names), be my guest. > > --snip > snip------------------------------------------------------------- > def ec_issubclass (class1, class2): > """A version of 'issubclass' that works with extension classes > as well as regular Python classes. > """ > > # Both class objects are regular Python classes, so use the > # built-in 'issubclass()'. > if type(class1) is ClassType and type(class2) is ClassType: > return __builtin__.issubclass(class1, class2) > > # Both so-called class objects have a '__bases__' attribute: ie., > # they aren't regular Python classes, but they sure look > like them. > # Assume they are extension classes and reimplement what > the builtin > # 'issubclass()' does behind the scenes. > elif hasattr(class1, '__bases__') and hasattr(class2, > '__bases__'): > # XXX it appears that "ec.__class__ is type(ec)" for an > # extension class 'ec': could we/should we use this as an > # additional check for extension classes? > > # Breadth-first traversal of class1's superclass tree. Order > # doesn't matter because we're just looking for a "yes/no" > # answer from the tree; if we were trying to resolve a name, > # order would be important! > stack = [class1] > while stack: > if stack[0] is class2: > return 1 > stack.extend(list(stack[0].__bases__)) > del stack[0] > else: > return 0 > > # Not a regular class, not an extension class: blow up > for consistency > # with builtin 'issubclass()" > else: > raise TypeError, "arguments must be class or > ExtensionClass objects" > > # ec_issubclass () > > > def ec_isinstance (object, klass): > """A version of 'isinstance' that works with extension classes > as well as regular Python classes.""" > > if type(klass) is ClassType: > return isinstance(object, klass) > elif hasattr(object, '__class__'): > return ec_issubclass(object.__class__, klass) > else: > return 0 > > # ec_isinstance () > --snip > snip------------------------------------------------------------- > > -- > Greg Ward - software developer gward(a)mems-exchange.org > MEMS Exchange / CNRI voice: +1-703-262-5376 > Reston, Virginia, USA fax: +1-703-262-5367 > > _______________________________________________ > Zope-Dev maillist - Zope-Dev(a)zope.org > http://lists.zope.org/mailman/listinfo/zope-dev > ** No cross posts or HTML encoding! ** > (Related lists - > http://lists.zope.org/mailman/listinfo/zope-announce > http://lists.zope.org/mailman/listinfo/zope ) >

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'issubclass' and 'isinstance' on ExtensionClasses
by Greg Ward 05 Jul '00

05 Jul '00

Hi all -- surely I'm not the first to deal with this: I use 'isinstance()' a lot, and 'issubclass()' occasionally, for run-time type-checking. This breaks when using ZODB Persistent classes, or any other type of ExtensionClass for that matter. I see no use of 'issubclass()' in the Zope lib/python directory, and only a few scattered uses of 'isinstance()'. (Checked both 2.1.5 and 2.2b2.) So maybe I *am* the first to worry about this. I'm surprised that ExtensionClass doesn't include enhanced versions of 'issubclass()' and 'isinstance()', though. So, here are my versions. Critiques welcome. In particular, is "type(X) is not ClassType and hasattr(X, '__bases__')" an adequate determination that X is indeed an extension class? If you folks want to include these with ExtensionClass (possibly with the leading "ec_" trimmed from the names), be my guest. --snip snip------------------------------------------------------------- def ec_issubclass (class1, class2): """A version of 'issubclass' that works with extension classes as well as regular Python classes. """ # Both class objects are regular Python classes, so use the # built-in 'issubclass()'. if type(class1) is ClassType and type(class2) is ClassType: return __builtin__.issubclass(class1, class2) # Both so-called class objects have a '__bases__' attribute: ie., # they aren't regular Python classes, but they sure look like them. # Assume they are extension classes and reimplement what the builtin # 'issubclass()' does behind the scenes. elif hasattr(class1, '__bases__') and hasattr(class2, '__bases__'): # XXX it appears that "ec.__class__ is type(ec)" for an # extension class 'ec': could we/should we use this as an # additional check for extension classes? # Breadth-first traversal of class1's superclass tree. Order # doesn't matter because we're just looking for a "yes/no" # answer from the tree; if we were trying to resolve a name, # order would be important! stack = [class1] while stack: if stack[0] is class2: return 1 stack.extend(list(stack[0].__bases__)) del stack[0] else: return 0 # Not a regular class, not an extension class: blow up for consistency # with builtin 'issubclass()" else: raise TypeError, "arguments must be class or ExtensionClass objects" # ec_issubclass () def ec_isinstance (object, klass): """A version of 'isinstance' that works with extension classes as well as regular Python classes.""" if type(klass) is ClassType: return isinstance(object, klass) elif hasattr(object, '__class__'): return ec_issubclass(object.__class__, klass) else: return 0 # ec_isinstance () --snip snip------------------------------------------------------------- -- Greg Ward - software developer gward(a)mems-exchange.org MEMS Exchange / CNRI voice: +1-703-262-5376 Reston, Virginia, USA fax: +1-703-262-5367

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Searching in a MySQL-Database
by Andre Schubert 05 Jul '00

05 Jul '00

Hi, i have a very important question. Is there a way to search in a mysql-database with the ZCatalog. Could i create a temporary file from a table and search it with the ZCatalog. If there are any Ideas please tell me. Thanks, as

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Zope contract job in Atlanta
by Frank Steele 05 Jul '00

05 Jul '00

Description: Zope/Python contract programmer. MTNI is a wireless media startup in Atlanta, GA. We're seeking a freelance developer with experience in Zope and Python to develop a messaging app. We offer wireless software/hardware solutions to a potential market of nearly 10 million US users/day. We need a smart, web-savvy developer who will need a minimum of handholding. Experience with SQL integration a plus, Zope on Unix/Linux experience preferred. If you're a good fit, this could very well turn into a permanent gig with equity. You will play a crucial role in our business. Preference for local developer(s), but willing to work with web-commuters. Company: MTNI Location: Midtown Atlanta, GA Contact: frank.steele(a)mtni.net mailto://frank.steele@mtni.net

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How to use document templates
by Jarkko Veijalainen 05 Jul '00

05 Jul '00

Hi! Where can i find S_I_M_P_L_E example of using document templates with zope/python. I have this external method, wich return several variables from object class. I want to embed to results in DTML page. The method is called from Zope by HTML form with 3 input attributes. Right now i have only managed to get obj.member in return plain screen. I can't use <dtml-var> tag, because i need to send those input values to the external method. ( i must be sound like real newbie, in fact i'm :) ) How i get those results in DTML page? Is the templates the answer or this there better way to this. jarkko

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Re: [Zope-dev] ZCatalog lexicon bug is back?
by Dieter Maurer 04 Jul '00

04 Jul '00

Chris Withers writes: > I seem to remember Michel being a little less than happy when he saw > that code. > > Quite frankly, I still don't have much confidence in (Z)Catalog (still > no docs for all the cool stuff, dodgy bugs and few responses when > they're raised...) which is a shame since it's Zope full text searching > mechanism... > > Chris > > PS: If that doesn't get a response, I give up ;-) I am very interested in ZCatalog. I promiss that I will look into it, when I come to 2.2. Currently, we are building a Zope 2.1.6 production site. So, I still stay focused with 2.1.6. My contributions to ZCatalog probably will not be ready for 2.2 final, but, if necessary, I will provide patches later. Dieter

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Re: [Zope-dev] Help needed: why is this DTML not working in zope 2 ?
by Gilles Lavaux 04 Jul '00

04 Jul '00

Argh!!! no, I made a typo error : it was .the syntax was good. Ok, I will use the new syntax in my new sites. But for my old site, I will not modify my ~500 dtml methods, except if there is a way to automate the change. Gilles -----Original Message----- From: Chris Withers <chrisw(a)nipltd.com> To: Gilles Lavaux <gilles.lavaux(a)esrin.esa.it> Cc: zope-dev(a)zope.org <zope-dev(a)zope.org> Date: Tuesday, July 04, 2000 1:33 PM Subject: Re: [Zope-dev] Help needed: why is this DTML not working in zope 2 ? >Gilles Lavaux wrote: >> But I found something: In my 'PUBLIC_Doc' document I display image with a >>  tag, my problem disappear if I use >> , someone can explain this?? > >Are you sure the space after the # isn't your problem? > >I would STRONGLY recommend moving your code to the new syntax, >especially if you are having problems. > >You should be aware that plans are afoot to remove the old syntax... > >cheers, > >Chris > >_______________________________________________ >Zope-Dev maillist - Zope-Dev(a)zope.org >http://lists.zope.org/mailman/listinfo/zope-dev >** No cross posts or HTML encoding! ** >(Related lists - > http://lists.zope.org/mailman/listinfo/zope-announce > http://lists.zope.org/mailman/listinfo/zope ) > >

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ZEO Replication/Cache
by Monty Taylor 04 Jul '00

04 Jul '00

I just installed an instance of ZEO Storage Server with a client on the same machine and a client on a different machine. So far, it seems to work reasonably well, with one exception. None of the changes I've made on one client seem to propagate to the other client unless I restart the other client. This can't be the intended modus operendi. Have I missed something obvious, or is the proactive notification from server to client not implemented yet? Monty

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Re: [Zope-PTK] Roles, Groups, Security and Group Membership
by Monty Taylor 04 Jul '00

04 Jul '00

>>>>>>>>>>>>>>>>>> Original Message <<<<<<<<<<<<<<<<<< On 7/4/00, 1:22:04 PM, Chris Withers <chrisw(a)nipltd.com> wrote regarding [Zope-PTK] Roles, Groups, Security and Group Membership: > Monty Taylor wrote: > > Am I making any sense at all? Does anyone see either a need for doing > > this or a way to do it? If it requires changes to PTK core, would anyone > > be interested in those, or should I throw them in my pile of dirty little > > secrets that no one should really know exist? > You're making perfect sense and I think it's a Zope problem partly, and > also a PTK problem. Good point. I think as ZEO becomes more prevelant and Zope wants to compete in the realm of big systems, group based interaction could serve to iron some things out. > The Zope problem is that Zope security has no idea about Groups. > As in Users/Members exist > There may have roles > They may also be members of Groups. > Groups may also be members of Groups. > Groups may also have roles associated with THEM. > Other major security systems I can think of (LDAP, Unix, NT, Notes) all > have this concept but Zope does not :( > Should this part of the discussion be moved to zope-dev? Probably so. I've forwarded the original email there and I'm sending this one to zope-dev. Any comments from the zope-dev world? Monty

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Fwd: [Zope-PTK] Area based roles?
by Monty Taylor 04 Jul '00

04 Jul '00

>>>>>>>>>>>>>>>>>> Original Message <<<<<<<<<<<<<<<<<< On 7/4/00, 12:45:29 PM, Monty Taylor <mtaylor(a)goldridge.net> wrote regarding [Zope-PTK] Area based roles?: > Hi all. I've got an idea of something I'm trying to implement, and I'm > wondering if the concept is of use to anyone else. > I've got an Intranet up in PTK. (What a shock, as I'm posting here. :) ) > I'm slowly getting people to use it for internal collaboration, et al. > But the main things people are wanting to do are internal to their own > department, with some overlap. So you've got: > +PTKRoot > | > +-Members > | +-John > | +-Sue > | > +-Marketing > +-Technology > Say John is in Technology and Sue is in Marketing. What I want is for > John to have Contributor rights in the context of Technology, and Sue in > Marketing, i.e. John adds a News Item and Publishes it. It shows up in > Technology but not Marketing. > I thought about creating a Technolgy Item ("Release Notes") and a > Marketing one ("Press Release") and then just having a catalog search on > the meta-type of each in the appropriate folder's index_html and give > them all Contributor. But that strikes me as unclean. It would be nice to > have anyone be able to create a Press Release or Release Notes, but only > have them published in their department's context, and merely pending in > others. > Am I making any sense at all? Does anyone see either a need for doing > this or a way to do it? If it requires changes to PTK core, would anyone > be interested in those, or should I throw them in my pile of dirty little > secrets that no one should really know exist? > Thanks, > Monty > _______________________________________________ > Zope-PTK maillist - Zope-PTK(a)zope.org > http://lists.zope.org/mailman/listinfo/zope-ptk > See http://www.zope.org/Products/PTK/Tracker for bug reports and feature requests

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