November 2000 - Zope-Dev

Automatic conversion to pdf format
by stefano.ciccarelli＠thewhitebird.com 15 Nov '00

15 Nov '00

<Newbie Alert> I am currently setting up a support website using Knowledge Kit. I would like to integrate it with ZpdfDocument, so that some documents could be automatically converted to pdf, without the need to cut and paste from Knowledge Kit to ZpdfDocument. Since I am a Zope newbie I did not find a way to make it work. I would really appreciate your help, Stefano Ciccarelli

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large PersistentMapping
by Robin Becker 15 Nov '00

15 Nov '00

I'm trying to build a Reverse Cross Referencing Product. The idea is to enable documents to know which other documents in the Zope data base are pointing at them. I would like to use a persistent mapping to store the link information, but since eventually the object might be quite large will I get a performance hit when accessing only a small part of the object. It certainly seems to work for small instances, but I'm worried about what happens as my structure gets larger. Is there an alternate way to do this? The heart of the object are the methods def __init__(self, id, title): '''Initialise a new instance of RXRef''' self.id=str(id) self.title = str(title) self.title = title self._N = PersistentMapping() def addNode(self,n): '''Add a new node if not known''' N = self._N if not N.has_key(n): N[n]=[] def addLinks(self,src,DST): '''We have a single src and multiple destinations''' if type(DST) not in SEQTYPES: DST = [DST] N = self._N for dst in DST: self.addNode(dst) if src not in N[dst]: N[dst].append(src) def delLinks(self,src,DST): '''We have a single src and multiple destinations''' if type(DST) not in SEQTYPES: DST = [DST] N = self._N for dst in DST: if N.has_key(dst): if src in N[dst]: N[dst].remove(src) if N[dst]==[]: del N[dst] def getRLinks(self,dst): '''get links pointing to dst''' N = self._N return N.has_key(dst) and N[dst][:] or [] -- Robin Becker

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Re: [Zope-dev] PythonMethods: Can't Slice context.REQUEST.PARENTS
by Dieter Maurer 15 Nov '00

15 Nov '00

Evan Simpson writes: > From: The Doctor What <docwhat(a)gerf.org> > > Using context.this().id, self.this().id, m_self.this().id > all get me > > the same things: > > Folder, Zope, and my method. None give me the DTML > Document > > foo_html. > > > > This would seem to be an important thing. > > The only information about your caller that you can get is > the contents of their namespace. So, in the final release, > you would be able to bind the caller's namespace to "_" and > write _.this().id. That requires a change to Zope, though, > so it doesn't work yet. You *could* work around this by > explicitly passing the namespace (or this(), for that > matter). Why can't I get the acquisition context as with External Methods? (if they are called directly via the Web, namespaces are not yet build and the acquisition context obtained via a "self" parameter is everything I have). Dieter

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Re: [Zope-dev] PythonMethods: Can't Slice context.REQUEST.PARENTS
by Dieter Maurer 14 Nov '00

14 Nov '00

The Doctor What writes: > Using context.this().id, self.this().id, m_self.this().id all get me > the same things: > Folder, Zope, and my method. None give me the DTML Document > foo_html. If it is indeed a DTML Document, then "this()" should reference this document. If it is a DTML Method, then "this()" will reference the methods 'client', usually the methods parent. > .... > Did you mean to do a this().id? That doesn't work at all, it gives > me a Name Error. No. I am not yet familiar with PythonMethods and what binding they define automatically. Obviously, you have "context", "m_self" and "self". My older PythonMethods installed seem to support only "self", but I am not sure. I would expect, that "context.this()" has the highest chance of success, maybe "self.this()". Note, that "foo_html" must be a DTML Document not a DTML Method! > There *must* be a way to do this. There is none for DTML Methods (other than modifying the code). Dieter

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Re: [Zope-dev] unbuffered html from external method
by Dieter Maurer 14 Nov '00

14 Nov '00

Andy McKay writes: > Is it possible to print unbuffered html output to the user from an external > method. It looks to me like I can't, output occurs upon the return and I > cant see a way of getting around that. "self.REQUEST.RESPONSE.write(....)" Be aware of the restriction of "HTTPResponse.HTTPResponse.write"! Dieter

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SQL Method Question
by Steven Grimes 14 Nov '00

14 Nov '00

I need to do a SQL Outer Join information from three different tables and display the results on a page and I can't figure out how to write the query in a single SQL method. I can't create a temporary table due to tight disk space. Any suggestions? Thanks Steven Grimes Database Engineer sgrimes(a)atinucleus.com Accelerated Technology, Inc. Mobile, AL www.atinucleus.com ------------------------------------------------------------ "Nucleus. All You NEED in an RTOS. Royalty Free." ------------------------------------------------------------

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Adding execute() to Zope DA's for use by External methods
by Brad Clements 14 Nov '00

14 Nov '00

I have Python code that I use outside of Zope, and inside Zope via external methods. This code uses database adapters (anything version 1 or later). When my code is used within Zope, I have in the past had two database connections from within the Zope process. One connection is the actual Zope DA (I'm using gvib) and the other is a python db connection. This has worked okay on Windows, but I'm getting strange lockup problems after moving to Linux. In any case, it seems to me the better way to do this would be to allow external methods to get db-like access to a zope DA. Most Zope DA's are built in db-sig type db connectors, so it seems like a relatively simple matter to define a new interface for Zope DA's to make available that supports execute semantics. The big issue in my mind is determining what kind of security needs to be applied to such a function, and how that security would be implemented. I suppose stealing roles/rights from SQL_Methods for use here makes sense. If you can call an SQL method, you can call execute() directly. Is there any support from the Zope community to add execute() like operations to Zope DA's? If yes, where should I start in figuring out security for this. And finally, how does an external method pass security information "back" to the DA? For example, I tried passing my Gvib instance to an external method. But when that method called the gvib instance to get a connection instance, it got a "no __call__ method" error. So then I tried passing the connection from dtml, ie <dtml-var "MyMethod(db=MyInterbaseConnection())"> but when MyMethod calls db.cursor() it gets a security error. Probably because this function isn't exposed by the security machinery. (same thing probably for the __call__ error) Brad Clements, bkc(a)murkworks.com (315)268-1000 http://www.murkworks.com (315)268-9812 Fax netmeeting: ils://ils.murkworks.com AOL-IM: BKClements

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Re: [Zope-dev] Observable Interface?
by Tres Seaver 14 Nov '00

14 Nov '00

Chris Withers <chrisw(a)nipltd.com> asked: > Does anyone know what happened to it and how far its implementation got? The preliminary implementaion, DefaultObservabale, landed as a mix-in class in Zope 2.2: $ZOPE_HOME/lib/python/OFS/DefaultObservable.py Mix it in to one of your Python base classes (be sure to get it's '__init__()' called!) and fire away. I am currenly working on the more ambitious notion of adding an event channel, which addresses some of the "MxN" problems which plague the classic Observer. See the Zope-PTK archives for August for the latest on that. Tres. -- =============================================================== Tres Seaver tseaver(a)digicool.com Digital Creations "Zope Dealers" http://www.zope.org

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ZPatters: Roles and remapping
by Roch'e Compaan 14 Nov '00

14 Nov '00

An Organisation can play the role of Customer and of Requester. In this case the Requester specialist will remap from the Customer specialist. In terms of roles all Customers do not play the role of Requester. Would it be correct to say that the remapping to Requester only occurs at that point in time, when the Customer plays the role of Requester and therefor becomes a Requester, as opposed to mapping the Customer to a Requester as soon as the Customer is created? In the latter case the Customer's rack pushes attributes to the Requester's rack and in the former the requester will first ask the Customer specialist for all Customers and then create a Requester for the Customer selected from the list. The reason I ask this is: Remapping in some way implies that the existence of the one implies the existence of the other. This is one place where frameworks colloborate and I think that colloboration should be carefully exercised so any input would be greatly appreciated. Roché

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Specialists, Racks, and Objects, oh my!
by Bill Anderson 14 Nov '00

14 Nov '00

I want a specialist to have two (or more hypotheticaly) racks, and each rack is to contain one type of object. I then want to be able to add objects. I have the two racks set up, but I am unclear as to how to specify that I want to add an item of a certain type, or to a certain rack. Ideas appreciated ... -- Bill Anderson Linux Specialist HPSO Thursday, November 02, 2000 Random Quote: Portable: survives system reboot.

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