October 2005 - Zope - Zope lists

resolving conflict errors
by Dennis Allison 10 Dec '05

10 Dec '05

Zope 2.7.6 I am a bit confused. I have a Zope DTML method that is generating ZODB conflict errors. The DTML method identified as producing the conflicts is a list of calls to other methods, conditionally executed. Most conflicts don't cause problems because the backoff and restart of the initial transaction will not have changed global state. In our particular case, the conflicting transaction has changed global state in our RDBMS so when it gets rerun, some RDBMS transactions are duplicated. And that's a problem. The solution, of course, is to resolve the conflicts properly. The first question: what data is generating the conflict? The DTML code and all the method references are static and unchanged. What data does Zope store in the ZODB when an object is evaluated? Presumably conflicts can be reolved programatically by setting a method on the object _p_resolveConflict( self, old, saved, new ) and returning one or another of the states (old, saved, new). It's not real clear how to do it. --

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Zope 2.8 or 3.1?
by HaraldFinnås 11 Nov '05

11 Nov '05

I'm new to Zope, and I've been playing with 2.8.1, but I really haven't done any real work with it yet. Now I expect to get my new decicated Zope hardware tomorrow, so I have to decide if I should go for 2.8.4 or 3.1.0. Any tips if I should go for the latest and greatest or stick with 2.8? I've also seen comments that running Zope on RHEL/CentOS might not be wise. My test env. is using FC4, but I'm planning to install CenOS 4.2 on the production server. Unwise choice? Regards, Harald

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Cannot show blob image from sql server
by Thomas G. Apostolou 01 Nov '05

01 Nov '05

Hi all, i have made an external method to connect and get data from an sql server 2000, and then show them in a table. All works fine but one of the columns i retrieve is a BLOB image witch makes my external method to crash. So i used z SQL Method (witch is not prefared because there is a lot of customization and that's why i used External Method with Python from the begining) and it goes fine with retrieving and showing the data. But still i cannot show the BLOB image as image. It shows as a very very long string. Any sugestion-solutions-readings would be most apreciated. Thanks A LOT. PS : Newbie 8-( Thomas G. Apostolou Software Engineer Θωμάς Γ. Αποστόλου Μηχανικός Λογισμικού

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Zope hangs with 'idle in transaction'
by Yuan HOng 01 Nov '05

01 Nov '05

Hi, list, I have a site running with Zope 2.7.6 under Linux. The site access a PostgreSQL database through ZSQL and psycopg 1.1.18. Only read access is used, nothing is written to the database. The one thing that annoys me very much is, with time passing, Zope will eventually hang and has to be restarted. When I use ps -Af to view the data connection status, I discovered that whenever Zope hangs, I can found all zope database connection in the status 'idle in transaction', like below: postgres 13605 799 0 16:22 ? 00:00:07 postgres: zopeapp backupdb 127.0.0.1 idle in transaction postgres 13611 799 0 16:22 ? 00:00:06 postgres: zopeapp backupdb 127.0.0.1 idle in transaction postgres 13614 799 0 16:22 ? 00:00:00 postgres: zopeapp backupdb 127.0.0.1 idle in transaction postgres 14078 799 0 16:26 ? 00:00:05 postgres: zopeapp backupdb 127.0.0.1 idle in transaction It seems zope is initiating some database transactions even though my site only access the database for reading. And those transaction somehow get into deadlock status and finally used up the maximun db connection allowed for zope. But why? How do I find out what zope is doing and why the connection are locked up? Any clue and direction pointing are heartily appreciated. Regards, -- Hong Yuan 大管家网上建材超市装修装潢建材一站式购物 http://www.homemaster.cn

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Permissions and Instances of ZClasses
by Dave Case 01 Nov '05

01 Nov '05

I'm trying to build a product through the ZMI (like the example in The Zope Book), I have some DTML methods in a ZClass were I want to be able to do a SecurityCheckPermission() on a permission that I have defined in the containing product. When I view the instance of the DTML, it doesn't see the permission. I'm able to at least see the 'View' permission... When I look around in the Permissions and Define Permissions of the various objects (both the ZClass, and the DTML methods), I don't see my permission in the lists, except for under 'Class Permissions' in the Permissions tab for the ZClass (were I have highlighted it, which I assume is correct?) The call to SecurityCheckPermission() looks like this... <dtml-if expr="_.SecurityCheckPermission('Manage Diary',this())"> I'm thinking maybe I'm calling SecurityCheckPermission in the wrong context? Making a product certainly can be confusing at times. :) Thanks! -- David Case Dav3xor(a)gmail.com www.builddiary.net

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Deleted users still have local roles?
by Robert Boyd 01 Nov '05

01 Nov '05

Hello, I'm seeing that if I assign a role on an object to a user, then delete the user, the object still lists the user as having the local role - and I can assign the non-existant user more local roles, too. Thus, no referential integrity between users and local roles. I suppose any of my code dealing with local roles can try to get the user first before displaying their id, to prevent showing these non-existant role-holders. Anyone deal with this issue before? I guess this stems from the fact that in Zope, objects know which users have local roles on them, but user objects don't know about the things they have local roles on (correct me if I'm wrong). Is this also the case in Zope 3? Often it's useful to be able to say "User A can do these things in relation to these objects" but in Zope it appears you have to inspect every object everywhere on the site in order to get this information. Rob

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zopeXMLMethods and zope 2.8.x
by Kees de Brabander 01 Nov '05

01 Nov '05

I succeeded using zopeXMLMethods up to zope 2.7.8 after adapting its __init__.py (see http://mail.zope.org/pipermail/zope/2005-February/156670.html by Anton Stonor), which was necessary starting with zope 2.7.3. Trying to use this very same zopeXMLMethods product (that is with adapted __ini__.py) in zope 2.8.4, however, resulted in exactly the same error I got with the original __init__.py in zope 2.7.8 (traceback below)??? Does anybody have a solution? cb Trying to add a xsltmethod in the zmi brings the authentication dialog up and results in an unauthorized error: Traceback (innermost last): Module ZPublisher.Publish, line 113, in publish Module ZPublisher.mapply, line 88, in mapply Module ZPublisher.Publish, line 40, in call_object Module Shared.DC.Scripts.Bindings, line 311, in __call__ Module Shared.DC.Scripts.Bindings, line 348, in _bindAndExec Module Products.PageTemplates.PageTemplateFile, line 110, in _exec Module Products.PageTemplates.PageTemplate, line 104, in pt_render - <PageTemplateFile at /qp/create> Module TAL.TALInterpreter, line 206, in __call__ Module TAL.TALInterpreter, line 250, in interpret Module TAL.TALInterpreter, line 651, in do_loop_tal Module Products.PageTemplates.TALES, line 206, in setRepeat Module Products.PageTemplates.TALES, line 221, in evaluate - URL: create - Line 70, Column 6 - Expression: standard:'here/availableProcessors' - Names: {'container': <App.ProductContext.__FactoryDispatcher__ object at 0x036A7E90>, 'context': <App.ProductContext.__FactoryDispatcher__ object at 0x036A7E90>, 'default': <Products.PageTemplates.TALES.Default instance at 0x02B8ABE8>, 'here': <App.ProductContext.__FactoryDispatcher__ object at 0x036A7E90>, 'loop': <Products.PageTemplates.TALES.SafeMapping object at 0x03710918>, 'modules': <Products.PageTemplates.ZRPythonExpr._SecureModuleImporter instance at 0x02B78E18>, 'nothing': None, 'options': {'args': ()}, 'repeat': <Products.PageTemplates.TALES.SafeMapping object at 0x03710918>, 'request': <HTTPRequest, URL=http://localhost:8080/qp/manage_addProduct/ZopeXMLMethods/create>, 'root': <Application at >, 'template': <PageTemplateFile at /qp/create>, 'traverse_subpath': [], 'user': admin} Module Products.PageTemplates.Expressions, line 185, in __call__ Module Products.PageTemplates.Expressions, line 173, in _eval Module Products.PageTemplates.Expressions, line 127, in _eval - __traceback_info__: here Module Products.PageTemplates.Expressions, line 301, in restrictedTraverse - __traceback_info__: {'path': ['availableProcessors'], 'TraversalRequestNameStack': []} Unauthorized: You are not allowed to access 'availableProcessors' in this context

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Silva
by Piotr Konstanty 31 Oct '05

31 Oct '05

I'm new in zope world. I would like to install Silva as a product in zope. When I put all core silva product to lib/python/Products cataloge unpack it an restart zope again every think seems to be good but when I want to do next step from INSALL.txt of Silva namely on "add list" of ZMI I choose Slva root and want to add it to zope root folder after I feed Id and Title on the "Add Silva Root" page and I push "Add" button I receive "HTTP 500 - Inside Error of server Internet Explorer". Where is an reason of this error? Any hints?

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marshall zsql results
by Christopher Rivard 31 Oct '05

31 Oct '05

Hello, I am having a little difficulty with a result object from ZSQL. The MySQL form input is a series of checkboxes that are creating a "mapping table". I have gone round and round and landed here: The checkboxes are marshalled as: list_map_dir_id:list:int SQL like this: <dtml-in list_map_dir_id> insert into listing_map (list_map_dir_id, list_map_list_id) values (<dtml-sqlvar sequence-item type=int>, <dtml-sqlvar list_map_list_id type=string> ) <dtml-var sql_delimiter> </dtml-in> MySQL data type is int for this column. All of this works fine, but ideally I would like to manipulate the id's as a list. I have tried a few variations and regularly run into "len of unsized object" if I try to insert as a varchar or insert the full list as [0,1,2,3,4] I have tried a few different MySQL data types, but no luck. Retrieving the results like this: select * from listing_map where list_map_list_id = <dtml-var list_id> And mapping them back to the directory table like this: select t1.* from directory as t1 left join listing_map as t2 on t1.dir_id = t2.list_map_dir_id where t1.dir_id = t2.list_map_dir_id && t2.list_map_list_id = <dtml-var list_id> Is there a way to marshall the results of this ZSQL object back into a list? I am branching the subsequent forms based on the above query results. The difficulty I am running into are exclusion situations A and B not C Seems like it would be easier if I could loop through and pull id's from a list. Maybe I'm asking the wrong question. Thanks in advance, Chris

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Newbe and zope 2.7 bugs?
by Tom Redfern 30 Oct '05

30 Oct '05

Sirs, I intend to build a Plone site and am hacking on it to get my feet wet. I seem to have run into some bug type problems with zope. The environment is pretty much out of the box: Suse Linux 9.3. python-2.4-14 zope-2.7.4-5 plone 2.0.5 When attempting to save security settings for acl_users, I run into the following: "Some permissions had errors: Manage users, View management screens". This occurs even if I've made no permission changes. The other problem I've run into is that if I set the properties of a document to allow discussion, I lose permission to view the document such that I have to blow off the document and recreate it to view it again. No problems are being loged. My question is: fix or upgrade? Is it a better plan to track down the problems and fix zope 2.7 as installed vi rpm by Suse, or is it the better plan to upgrade to zope 2.8? Have these issues been addressed? I'm at the very bottom of the development of this site, so I'm leaning toward getting all the latest stuff installed before proceeding, but any suggestions/comments would be appreciated. Thank you. -- ---------------------------------------------------------------------- * Tom Redfern | Address: 23015 Edmonds Way Apt #A43 Edmonds WA 98020 * * | Phone: 425-778-5320 * ----------------------------------------------------------------------

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