September 1999 - Zope-Dev

(no subject)
by Ping Lau 27 Sep '99

27 Sep '99

>If you can choose your DB, then why not use one that has transactions ? > >Have you checked PostgreSQL (http://www.postgresql.org/) it has more >complete >SQL support, including transactions. It is slower than MySQL on simple >queries, >about same or faster on more complex ones. In fact, PostgreSQL is my second choice after MySQL. But after reading the ZODB features, I am trying to see whether or not ZODB is suitable for my project. If it is suitable, I might as well take the advantage of it & save me some works from messing with RDBM. Regards, Ping __________________________________________________ Do You Yahoo!? Bid and sell for free at http://auctions.yahoo.com

2 1

Barriers to Zope popularity: Part 1: wysiwig editing
by Jay, Dylan 27 Sep '99

27 Sep '99

Having been using Zope for the past 8months or so I see two potential reasons as to why more people at my work havn't taken to Zope. One discussed of late is WYSIWYG editing. I HATE wysiwyg editing. It invariably makes a mess. It seems that a lot of people disagree with me and find a system that allows wysiwyg editing to make the creation of good web pages simplier. Possible solution: Frontpage seems to me to be the weapon of choice for these "amateur" web authors. I imagine that frontpage will support webdav in the future but for now I think it would be possible to support a subset of the frontpage web extensions. At least the ones that deal with authoring etc. It all uses HTTP so I imagine it would be as hard to implement as webdav support was. Products could even be created for searching and web discussion extensions but I would think that this would detract from Zope and add support for frontpage more than the reverse. The next problem with this is how to edit partial pages in a wysiwyg editor. Ie how to edit a whole page when every DTML doc has <dtml-var standard_html_header> etc in. What we could do is to have a special render method that produces an html document which has all the html the real rendered page does as well as the DTML cunningly encoded in it. Then a special update method can take this an process the changes to the parts of the document as neccesary. For instance  <h2></h2> <p> This is the  Document. </p>  could be rendered as  <html> <head> <body>  <h2>My Documents Title</h2> <p> This is the myDoc Document. </p>  </body>  or something similar. As long as ALL the dtml in a document can be encoded in this way and the visual editor leaves the comments alone then this will work. This leads to the question of how the update method will deal with updates to include documents/methods/properties? Not sure. It could either, give an exception (might be possible with WEC), just ignore them, or try and perform the updates on the other objects (potentially messy but possible in limited cases???). Thoughts?

12 21

RE: [Zope-dev] Re: Transaction support on MySQL
by Michel Pelletier 27 Sep '99

27 Sep '99

Thanks Rik, for removing the cross post on this thread. It's pretty tiring to read the same thread of discussion twice, especially since I try to read every message that goes by. The original poster was probably looking for the broadest possible audience to answer his/her question. When you folks see a coss-post to zope-dev, think for a second before automaticly replying to 'all recipients'. If you think the discussion should really go two ways, then the cross-post is ok. If it's going for broad audience, take it over to the big list. if it's a development question, take it off the big list and keep it on zope-dev. Thanks, -Michel > -----Original Message----- > From: Rik Hoekstra [mailto:fghoekstra@cit10.wsd.leidenuniv.nl] > Sent: Monday, September 27, 1999 3:35 AM > To: zope-dev(a)zope.org > Subject: RE: [Zope-dev] Re: Transaction support on MySQL > > > <snip> > > > I have a dynamic PDF generation library and a minimal html to PDF > > conversion script (enough to support Structured Text) all written in > > Python. No table support yet. > > > > You can get it from: > > http://starship.python.net/crew/pavlos/ > > > > It was originally intended to provide PDF support for Zope > but it is a bit > > slow, unless some caching scheme is used. > > > > There is one more PDF library for python by Andy Robinson > but I do not > > remember the URL. > > > > Pavlos > > > > The freely available (for non-commercial purposes, check out > the licence) > pdflib by Thomas Mertz also has a python binding. It is > intended for pdf > publishing on www sites and it is fast. URL http://www.pdflib.com > > Rik > > > > _______________________________________________ > Zope-Dev maillist - Zope-Dev(a)zope.org > http://www.zope.org/mailman/listinfo/zope-dev > > (To receive general Zope announcements, see: > http://www.zope.org/mailman/listinfo/zope-announce > > For non-developer, user-level issues, > zope(a)zope.org, http://www.zope.org/mailman/listinfo/zope ) >

1 0

Re: [Zope-dev] __init__.py does not work
by Phillip J. Eby 27 Sep '99

27 Sep '99

At 06:15 PM 9/27/99 +0800, Victor Zhai wrote: > >import Person > >from ImageFile import ImageFile Try: from Person import Person,manage_addUserDb,manage_addUserDbForm Also, your meta_types dictionary says 'manage_addPersonDbForm' when it should say 'manage_addUserDbForm'. Hope that helps.

1 0

RE: [Zope-dev] Re: Transaction support on MySQL
by Rik Hoekstra 27 Sep '99

27 Sep '99

<snip> > I have a dynamic PDF generation library and a minimal html to PDF > conversion script (enough to support Structured Text) all written in > Python. No table support yet. > > You can get it from: > http://starship.python.net/crew/pavlos/ > > It was originally intended to provide PDF support for Zope but it is a bit > slow, unless some caching scheme is used. > > There is one more PDF library for python by Andy Robinson but I do not > remember the URL. > > Pavlos > The freely available (for non-commercial purposes, check out the licence) pdflib by Thomas Mertz also has a python binding. It is intended for pdf publishing on www sites and it is fast. URL http://www.pdflib.com Rik

2 2

__init__.py does not work
by Victor Zhai 27 Sep '99

27 Sep '99

When I creat a instance of Class Person. Zope says: Zope Error Zope has encountered an error while publishing this resource. Resource not found Sorry, the requested Zope resource does not exist. Check the URL and try again. Troubleshooting Suggestions The URL may be incorrect. The parameters passed to this resource may be incorrect. A resource that this resource relies on may be encountering an error. For more detailed information about the error, please refer to the HTML source for this page. If the error persists please contact the site maintainer. Thank you for your patience. My Person.py file like this: ----------------------------------------------------------------- __version__='$Revision: 1.13 $'[11:-2] import Persistence import ZODB manage_addUserDbForm = HTMLFile('addUserDb',globals()) def manage_addUserDb(self, name, age, REQUEST=None): """Add a Person instance to Zope """ self._setObject(name,Person(name,age)) if REQUEST is not None: #Display the Folder that contain the new Person return self.manage_main(self,REQUEST) class Person(Persistence.Persistent): """A Persistent Person """ def __init__(self, name, age): self.name = name self.age = age ------------------------------------------------------------------- My __init__.py like this: -------------------------------------------------------------------- __doc__="""Person product $Id: __init__.py,v 1.3 1998/07/16 13:26:54 brian Exp $""" __version__='$Revision: 1.3 $'[11:-2] import Person from ImageFile import ImageFile meta_types= ?'name':'Person', 'action':'manage_addPersonDbForm' ?, methods=? 'manage_addUserDbForm': Person.manage_addUserDbForm, 'manage_addUserDb': Person.manage_addUserDb, ? misc_=?'UserDb_icon': ImageFile('UserDb_icon.gif', globals()), 'User_icon': ImageFile('User_icon.gif', globals()), ? __ac_permissions__=( ('Add Person Dbs',('manage_addUserDbForm','manage_addUserDb')), ('Change PersonDbs',()), ) -------------------------------------------------------------------------- addUserdb.dtml file like this <HTML> <HEAD> <TITLE>Add Person Db</TITLE> </HEAD> <BODY BGCOLOR="#FFFFFF" LINK="#000099" VLINK="#555555" ALINK="#77003B"> <h2>Add User Db</h2> <FORM ACTION="manage_addUserDb" METHOD="POST"> <TABLE CELLSPACING="2"> <TR> <TD ALIGN="LEFT" VALIGN="TOP"> <STRONG> Authentication Type </STRONG> </TD> <TD ALIGN="LEFT" VALIGN="TOP"> Username is: <INPUT TYPE="TEXT" NAME="name" VALUE="Victor.zhai"> <BR> Age is: <INPUT TYPE="TEXT" NAME="age:int" VALUE="26"> </TD> </TR> <TR> <TD></TD> <TD><BR><INPUT TYPE="SUBMIT" VALUE="Add"></TD> </TR> </TABLE> </FORM> </BODY> </HTML> ================================================================================== "WorldSecure Server <ogilvy.com>" made the following annotations on 09/27/99 06:21:21 ------------------------------------------------------------------------------ Privileged/Confidential Information may be contained in this message. If you are not the addressee indicated in this message (or responsible for delivery of the message to such person), you may not copy or deliver this message to anyone. In such case, you should destroy this message and kindly notify the sender by reply email. Please advise immediately if you or your employer does not consent to email for messages of this kind. Opinions, conclusions and other information in this message that do not relate to the official business of the Ogilvy Group shall be understood as neither given nor endorsed by it. ==============================================================================

1 0

Re: Transaction support on MySQL
by Bjorn Stabell 27 Sep '99

27 Sep '99

Evan wrote: > Unless you want to generate PDF or Postscript files on the fly, you are > *not* going to get what you want from a browser-based application, > regardless of the server. Neither Zope nor any other Web App can > control how your browser will print an HTML page (AFAIK). There is a PDF package for Perl, but I don't know of any for Python. If there are, then you can relatively easily generate PDF on the fly. Another option is to use Flash; although I'm not sure you can control the size very well, you can control the relative position very well, and Flash 4 can even get data dynamically from the server so the Flash file can remain the same while the data it shows can easily be changed. It would be cool if someone developed a system that used PDF or Flash instead of HTML as the default presentation format, but that got all the data from (text) objects in Zope. Both PDF and Flash support hyperlinks, so it should be doable. Bye, -- Bjorn Stabell <bjorn(a)stabell.priv.no>

3 2

Re: [Zope-dev] Transactions support on MySql
by Ping Lau 27 Sep '99

27 Sep '99

> Ping wrote: >> 1. From what I read, Zope supports transactions. If I >> want to use MySql as my backend database, can Zope >> still support atomic operations since MySql does not >> support transactions? > > Evan wrote: >Zope will still support transactions on *Zope objects*. Your MySQL >database will not participate in the transaction, so all SQL statements >executed will remain in effect even if the Zope transaction aborts. >You might be able to handle this with explicit logging in MySQL, if the >changes aren't too complicated. Another alternative I have in mind is using ZODB to store my business objects. Has anyone used ZODB as the backend? How stable is it? In terms of doing query, does Zope have a similar SELECT statement in RDBM? Regards, Ping

3 2

Philosophy.__of__(Acquisition).questions
by Evan Simpson 26 Sep '99

26 Sep '99

I thought I understood Acquisition, until I read the docs at http://www.digicool.com/releases/ExtensionClass/Acquisition.html. *Really* read them, until my brain hurt, then I went and had a lie down, then tried again. Now I'm *really* confused! Let me take the example from the docs: We have a tree that includes paths a/x and a/b/c. Whenever we ask an object which supports acquisition for an attribute which turns out to support acquisition, we are given a wrapper which preserves the context. Using 'of' to mean 'in the context of', the general transformation rule is (path/top/attr) -> (path/attr) of (path/top) if attr is not an element of top, or (path/attr) -> (attr of path) if it is. Here are some access paths and the resulting wrapper objects: a/b b of a a/b/c c of (a/b) -> c of (b of a) a/x x of a a/b/x (a/x) of (a/b) -> (x of a) of (b of a) a/b/c/x (a/b/x) of (a/b/c) -> ((a/x) of (a/b)) of (a/b/c) -> ((x of a) of (b of a)) of (c of (b of a)) Once a wrapper is written in 'of' notation, you can read off the acquisition order from left to right, skipping repeats. Thus, for 'a/b/c', the acquisition order is c, b , a, while for 'a/b/c/x' it is x, a, b, c. The addition of x reverses the acquisition sequence for the previous step! If x were contained in b instead, then we would have a/b/c/x -> (a/b/x) of (a/b/c) -> (x of b of a) of (c of b of a), giving sequence x, b, a, c!! This seemed horribly unintuitive to me, since I thought that an acquired object was only given the context of the object which started the acquisition search. This would lead to the same result for 'a/b/c', but 'a/b/c/x' would give x, c, b, a. Jim Fulton kindly explained, in another thread, how the acquired object's context is searched before the acquiring object's. Fine, that's fully consistent with all of the above. Now I try it out in Zope. I make nested folders 'a/b/c' in the root. I put DTML method 'x' in 'a', and have it display <dtml-var prop>. I give a, b, and c properties named 'prop', containing 'a!', 'b!', and 'c!' respectively. I call '/a/b/c/x' and it prints 'c!' What the hell? According to the docs, shouldn't it print 'a!'? Ok, let's try making DTML Method y in c with body "<dtml-var x>". Same result. How about "<dtml-with x><dtml-var prop></dtml-with>"? Same thing. Help??

3 2

Transactions support on MySql
by Ping Lau 26 Sep '99

26 Sep '99

Hello, I am a newbie. I have a few questions to ask. 1. From what I read, Zope supports transactions. If I want to use MySql as my backend database, can Zope still support atomic operations since MySql does not support transactions? 2. The project I will work on requires a lot of very customized reports to be printed on blank paper as well as pre printed form. I have used Delphi from my previous project. I used the report writter came with Delphi to design & print all sorts of report on all kinds of papers (blank, pre printed form, labels, etc). How can I produce reports for printing to pre printed form? 3. My project also requires barcode (Code39) printing on labels feed from dot-matrix printers. Where can I find barcode module or class for Zope? I would like to say thank you in advance for your answers, tips, or pointers. Regards, Ping __________________________________________________ Do You Yahoo!? Bid and sell for free at http://auctions.yahoo.com

2 1