June 2005 - Zope - Zope lists

Newbie Questions - many-many relationships? Zope 2 or 3?
by Jim Vine 02 Jul '05

02 Jul '05

Database Question Hello, I'm a newbie, so this is a newbie question! I am currently preparing to build a web application for property lettings, and I'm very interested in what Zope has to offer. The application will need to recognise a number of different objects, such as "houses", "prospective tenants" and "property owners" (the latter of which I may implement as user types, which would allow these people to log in and amend some of their own information.) I'm very interested in the Object Oriented way of doing things; for example, I'm thinking about implementing houses as a folder-ish object, so it would be able to contain photos of the house in question. The biggest stumbling block I am facing is how to do something "Relational" in an OO environment. Specifically, I've been scratching my head for a while about how to handle a many-many relationship: a property owner may own more than one house; conversely, a house may have more than one co-owner - consequently it's not appropriate to have either containing the other. I've googled for general information about handling many-many relationships in OO, and most of what I've come across has only indicated that it can be tricky! Having a look through past threads on this mailing list I've noticed a few references to mxmRelations (http://www.zope.org/Members/maxm/products/mxmRelations) which seems to match up - have I got the right end of the stick? Before I jump in with this I'd appreciate any advice or guidance you could provide - it'd be greatly appreciated. While Im on, Ive noticed that Zope 3 has been released. Is this now the recommended development environment, or am I better off sticking with Zope 2 for now, and porting my application once Zope 3 is a bit further down the line? Id greatly appreciate any guidance that can be provided on these subjects. Thanks in advance, Jim ___________________________________________________________ Yahoo! Messenger - NEW crystal clear PC to PC calling worldwide with voicemail http://uk.messenger.yahoo.com

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Import problem
by George Tesseris 01 Jul '05

01 Jul '05

When I try to import a specific .zexp the following error is raised: *Error Type: AttributeError* *Error Value: ('__new__', <function __newobj__ at 0x00B8B0F0>, (<extension class Shared.DC.ZRDB.DA.SQL at 01AE2728>,)) *Help please... It's crucial... George **

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Problem with ZSQLMethods/MySQL after update
by Ragnar Beer 01 Jul '05

01 Jul '05

Hi everybody! After upgrading Zope from version 2.6.4 to 2.8.0 and mysqlpython from 0.9.2 to 1.2.0 I cannot add or edit ZSQLMethods anymore, although there is an open (MySQL)db-Connection that works just fine with the same ZSQLMethods that cannot be edited or with external methods. The error I'm getting is: "There are no SQL database connections. You need to add a Zope SQL database connection before you can edit a Zope SQL Method." This happens only when using my old zope instance (which I need to) but not when using a freshly created zope instance. Is this a known problem? I couldn't find anything in my zope mailing list archive. Cheers, Ragnar P.S.: Here are the contents of my ProductManagement screen: BTreeFolder2 (Installed product BTreeFolder2 (BTreeFolder2-1.0.1)) 2005-06-20 10:35 DocFinderEverywhere (Installed product DocFinderEverywhere (DocFinderEverywhere-0.4.1)) 2003-02-14 08:39 ExternalMethod (Installed product ExternalMethod (External Method-1-0-0)) 2000-10-12 15:51 Five (Installed product Five (Five 1.0.1)) 2005-06-20 10:35 MIMETools (Installed product MIMETools) 2001-01-05 14:31 MailHost (Installed product MailHost (MailHost-1-3-0)) 2003-05-11 23:00 OFSP (Installed product OFSP (OFSP-1-0-0)) 2000-10-12 15:51 PageTemplates (Installed product PageTemplates (PageTemplates-1-4-0)) 2002-05-07 13:53 PluginIndexes (Installed product PluginIndexes) 2001-09-04 13:29 PythonScripts (Installed product PythonScripts (PythonScripts-2-0-0)) 2001-09-04 10:13 Sessions (Installed product Sessions) 2002-05-07 13:53 SiteAccess (Installed product SiteAccess (SiteAccess-2-0-0)) 2001-09-04 11:38 SiteErrorLog (Installed product SiteErrorLog) 2003-02-14 08:39 StandardCacheManagers (Installed product StandardCacheManagers (StandardCacheManagers-1-1-0)) 2001-09-04 10:13 TemporaryFolder (Installed product TemporaryFolder) 2002-05-07 13:53 Transience (Installed product Transience) 2002-05-07 13:53 ZCTextIndex (Installed product ZCTextIndex) 2003-02-14 08:39 ZCatalog (Installed product ZCatalog (ZCatalog-2-2-0)) 2000-10-12 15:51 ZGadflyDA (Installed product ZGadflyDA) 2001-01-05 14:31 ZMySQLDA (Installed product ZMySQLDA (ZMySQLDA 2.0.8)) 2003-11-30 20:17 ZODBMountPoint (Installed product ZODBMountPoint) 2005-06-20 10:36 ZReST (Installed product ZReST (1.1)) 2005-06-20 10:36 ZSQLMethods (Installed product ZSQLMethods) 2000-10-12 15:51 ZopeTutorial (Installed product ZopeTutorial (Zope Tutorial 1.2)) 2005-06-20 10:36

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Checking for an Integer Argument
by Asad Habib 30 Jun '05

30 Jun '05

Is there any way to check if an argument is an integer in Python? Offcourse, there is the int function but it chokes when passed an argument that is not a string and then the user is inconvenienced (it throws a ValueError to be specific). I guess I could check each digit of the integer to determine if its ASCII value falls within the appropriate range and if each digit passed this test, then the entire number would be an integer. Does anyone know of a simpler way that involves use of a predefined Python function? Likewise, does anyone know if a similar function exists to detect floating point numbers? Any help would be appreciated. Thanks. - Asad

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how to get info about an object (dir/type)
by gabor 30 Jun '05

30 Jun '05

hi, while working with zope, i many times have the following problem: i find a method that i can use, and the documentation (for example) says: "returns the current user". ok, but what kind of object is it? what methods does it have? usually i would simply call dir() or type() on the result object, but those are forbidden in zope. how do you usually solve this? gabor

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Calendar for Zope
by John Poltorak 30 Jun '05

30 Jun '05

I quite like Plone's Calendar, but need something similar for Zope. Any recommendations? -- John

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TAL and Javascript
by Rob Boyd 29 Jun '05

29 Jun '05

Thanks to all the responders. It gave me some ideas, but alas no luck. To clarify, I am not trying to do everything in one request. Request one generates the page, a user event (selecting an option from a form) fires another request via javascript. like: <script tal:content="python:'function getFormats() { var widget = document.getElementById('orgs'); var chosen_org = widget.options[widget.selectedIndex].value; var formats = %s; // build selection 2 options from formats ' % here.getDataFormats(chosen_org)" /> And then a user event (onChange) calls getFormats. Even with generating the script with a Python script or DTML, the problem remains (for me at least) to get a value from the DOM passed as an argument to a Python script that queries my database. If my Python script didn't take an argument, I'd have no problem. I could do this and use javascript to build the select options from the appropriate values. But I'd like to cut down on what the browser has to handle. What the user chooses in the first selection can reduce what they get to choose in selection two from 3000 choices to hundreds. I'd prefer to have the backend reduce the result set rather than having the browser do the work. I thought about AJAX (no experience), but given time constraints, looks like I'll have to load everything on the page and go from there. Rob ____________________________________________________ Yahoo! Sports Rekindle the Rivalries. Sign up for Fantasy Football http://football.fantasysports.yahoo.com

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TAL and Javascript
by Rob Boyd 29 Jun '05

29 Jun '05

I'm stuck this, and would appreciate help or pointers. I have a form with 2 selection drop-downs. I want the user's choice of select 1 to drive the options displayed in select 2. When the user makes a selection in select 1, onChange calls a Javascript function that should write select 2 options based on the result of a call to a Python script, passing the select 1 choice as an argument to the Python script. But: I cannot get the Javascript var into the namespace that the TALES expression knows about. Example: <script> function makeDropDown() { var widget = document.getElementById('select1'); var choice = widget.options[widget.selectedIndex].value; var data = [result of calling Python script 'foo(arg)' with arg=choice] // create options for select 2 } </script> [various html...] <select id="select1" onChange="makeDropDown()"> [options...] </select> I've tried with multiple scripts, where one has tal:content=... but cannot figure out how the TALES expression can get at what my javascript gets from an event. I haven't done much with JavaScript inside Page Templates, so perhaps I'm going about this all wrong. TIA, Rob __________________________________ Discover Yahoo! Stay in touch with email, IM, photo sharing and more. Check it out! http://discover.yahoo.com/stayintouch.html

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WebDAV
by Luiz Fernando B. Ribeiro 29 Jun '05

29 Jun '05

I'm using webdav to update to access files from Dreamweaver and it is working fine but when I try to use windows web folders feature it fails with the following error in zope log. It seems that windows is requesting the PROPFIND before authenticating. Any clues? Zope Version (Zope 2.7.5-final, python 2.3.5, linux2) Python Version 2.3.5 (#2, May 4 2005, 08:51:39) [GCC 3.3.5 (Debian 1:3.3.5-12)] System Platform linux2 Time 2005/06/27 15:05:48.973 GMT-3 User Name (User Id) Anonymous User (None) Request URL http://my.server/clientes/PROPFIND Exception Type Unauthorized Exception Value <strong>You are not authorized to access this resource.</strong> Traceback (innermost last): * Module ZPublisher.Publish, line 92, in publish * Module ZPublisher.BaseRequest, line 449, in traverse * Module ZPublisher.HTTPResponse, line 680, in unauthorized Unauthorized: <strong>You are not authorized to access this resource.</strong> Thanks in advance, -- Luiz Fernando B. Ribeiro Engenho Soluções para a Internet +55 11 6959-7610

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Sequencing pages
by John Poltorak 29 Jun '05

29 Jun '05

If I create individual pages for a website as sub folders of a sites main folder, how do I control the sequence of pages if I automatically generate a set of links to all the folders? I presume that under normal circumstances that sequence would be in alphabetical order of object ID. -- John

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