March 2000 - Zope-Dev

Re: [Zope-dev] Pointer or reference object
by Jason Spisak 07 Mar '00

07 Mar '00

Itamar Shtull-Trauring writes: > Jason Spisak wrote: > > > I had thought that Itamar's code below created an object that was exactly > > like the object at the URL. More like a copy. A duplicate. It that > > right? > > No, it doesn't create a duplicate - it actually links twice to the same > object. > > > what do you mean by reference count? Something that keeps track of all the > > references in the ZODB in one place. An authority? > > Python has a reference count for each object. When it reached 0 the object > is deleted. Consider the following example: > > >>> x = [] > >>> a = x # a and x both point at the same object > >>> a.append(3) # so if we change a... > >>> a > [3] > >>> x # ...x is also changed > [3] > >>> del x # this does not free any memory since a still points at this object > >>> x > Traceback (innermost last): > File "<stdin>", line 1, in ? > NameError: x > >>> a # a still points at the data > [3] > > -- > Itamar S.T. itamars(a)ibm.net Jason Spisak CIO HireTechs.com 6151 West Century Boulevard Suite 900 Los Angeles, CA 90045 P. 310.665.3444 F. 310.665.3544 Under US Code Title 47, Sec.227(b)(1)(C), Sec.227(a)(2)(B) This email address may not be added to any commercial mail list with out my permission. Violation of my privacy with advertising or SPAM will result in a suit for a MINIMUM of $500 damages/incident, $1500 for repeats.

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Re: [Zope-dev] Pointer or reference object
by Jason Spisak 07 Mar '00

07 Mar '00

I meant to use resolve_url, to find any references to an object upon it's deletion. Changes in an object's state really wouldn't matter if there is a way to truely 'mirror' an object. The name spaces would have to either be selectable, or since it is a mirror, then it aquires the name space of the object that it is mirroring (and exact mirror). Like I said, I don't have any idea if this 'pointer' is even possible in the ZODB. Anyone from DC thinkning about this? All my best, Jason Johan Carlsson writes: > > Yes, I have thought about it. > > One solution I thought of is use an object referens counter > base class for "referencable objects". > The base class should be responsible for manageing references > and take action on the references when the objects state changes. > > One problem is how to handle acqusition. > Should the referenced object be viewed in it's own context or > the reference objects context? Or should the contexts merge? > > > How did you intend to use ZCataloges for the ZMirror? > > > //Johan > > > > > > Zopsters, > > > > This is very out of the blue, but has anyone thought about tackling the > > 'reference' question by using a phantom Zope object? I don't know > > nearly enough Python to answer this question, but maybe someone can. > > > > Is it possible to create a 'Reference' object that really stores the url > > of another object and maquerades as the other object's meta_type. > > Anything that is asked of the 'Reference' object, just get's passed > > along to the real object in it's place? Obviously whenever you delete > > an object any 'References' with that object's url stored in them get > > deleted too(ZCatalog could hold these). Sort of like a reflective > > mirror. You see the object in the mirror but you aren't actually > > looking at the object, you are looking at the mirror. A ZMirror. > > > > All my best, > > > > > > -- > > Jason Spisak > > 444(a)hiretechs.com > > > > _______________________________________________ > > 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 ) > > > Jason Spisak CIO HireTechs.com 6151 West Century Boulevard Suite 900 Los Angeles, CA 90045 P. 310.665.3444 F. 310.665.3544 Under US Code Title 47, Sec.227(b)(1)(C), Sec.227(a)(2)(B) This email address may not be added to any commercial mail list with out my permission. Violation of my privacy with advertising or SPAM will result in a suit for a MINIMUM of $500 damages/incident, $1500 for repeats.

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Re: [Zope-dev] unpickleable error
by auto44082＠hushmail.com 07 Mar '00

07 Mar '00

>what gets assigned to 'upload_file' is probably not pickleable. What >that is I don't know, you will have to find out what kind of object >is >getting assigned or is trying to store itself as a property. This is >just a guess, there is not enough information to pin it down exactly. > >-Michel I'm assigning a Microsoft Word document to "upload_file". I suppose I can try other types of files such as simple text. I know that MSWord files are binary in nature. If this poses a problem then I am truely confused. When the Zobject I'm working with is created. I can assign a word document to the upload_file property without issue. There are no errors. I am able to manipulate it, read/write it to a local OS file, etc. The only difference, is that on object initialization, I create the property instead of change it as it does not yet exist, using the manage_addProperty method. I pass the method REQUEST['new_file'] just like I did in the example I posted to the list. Do you or anyone else have any other ideas. Maybe I need to creat the property in this case as well? -Andy IMPORTANT NOTICE: If you are not using HushMail, this message could have been read easily by the many people who have access to your open personal email messages. Get your FREE, totally secure email address at http://www.hushmail.com.

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Re: [Zope] Zope sendmail tag inconsistent
by Hannu Krosing 07 Mar '00

07 Mar '00

Jason Spisak wrote: > > Zopists, > > Has anyone else noticed that the endmail tag will sometimes not send a > mail even though the dtml method sucessfully completes? It's about one > out of ten at high traffic times, and it happened on Zope.org too when I > tested it by emailing my password to myself a few times. I had a system where it failed (also silently) every first time after reboot. I just moved to an external method that used /usr/sbin/sendmail as I did not have enough time to start debugging. Telnet to port 25 had just a very long (>30 sec) startup time, probably some DNS problem. AFAIK Zope does not (for some unknown reasons to me) use pythons SMTPlib but has rolled their own smtp interface. It has also been reported to fail with MS Exchange server, which someone fixed for himself by swithing to smtplib. IIRC the patches were also posted to zope or zope-dev list. IMHO the right solution for Zope would be swithing to smtplib, and if there are faults then fix them there (and maybe include fixed smtplib with Zope until fixes are included in mail python distro). There is no need to invent to similar but slightly and differently broken wheels, at least in Open Source Software there aint. ----------------- Hannu

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ZPublisher and Apache
by Kaweh Kazemi 07 Mar '00

07 Mar '00

hi all, first: i am a ZOPE newbie, so please be patient. :) what i've done til now: i've installed Apache (1.3.9 on Win2K) and i am using httpdapy to access Python-CGI-scripts. i've done some CGI programming before, and realized, that maintaining good CGI scripts is hard work. :) then i found ZPublisher (AFAIK called BOBO before, right), which i liked very much. i read the article at http://classic.zope.org:8080/Documentation/Reference/ObjectPublishingIntro and was fascinated. that was exactly what i needed. so, i got ZOPE, and got ZPublisher to work with httpdapy. great. but now i am constantly running into problems: ZPublisher works great. but i also want to use DocumentTemplate and ZODB. DocumentTemplate works ok, but if i change a .dtml, the new file isn't reloaded, so i have to restart the server, to see my changes. i know, that this is not ZOPEs fault - httpdapy is only reloading modules, which have changed, so i have also to "change" the module, which loads the .dtml file. maybe someone has a better solution? ZODB can't be used in that constellation, cause the database is locked, and if i change the main module, i get a error: StorageSystemError: Could not lock the database file. There must be another process that has opened the file. just to be clear: i *know*, why this problems arise (well at least i have an idea). my question is: is there a way to improve the situation (i don't want to restart the web-server every time, i do a change). would it be better to use ZServer? but i don't need the "content manager" stuff. i just want to publish different types of objects (one represents a bug-database, another an archive database, ...) using ZODB to store the objects and using DocumentTemplate for defining the user-interface. i hope, i could make my problems clear. thank you for any help, you can give me, ----------------------------- .....coming from Kaweh Kazemi neo Software Produktions GmbH Email: kaweh(a)neo.at Look at: http://www.neo.at

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extend the Zope objects using java
by Ranjith Babu 07 Mar '00

07 Mar '00

Hi I am a java developer.I want to extend the Zope objects using java..Is it possible ? Anybody have any idea about how to create a wrapper class in Java for Zope objects so that we can extend the Zope..? Regards Ranjith Babu ____________________________________________________________________ Get free email and a permanent address at http://www.netaddress.com/?N=1

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CatalogAwareness mod
by James W. Howe 06 Mar '00

06 Mar '00

I've noticed that the manage_editCataloger code in 2.1.3 (and later?) still requires a REQUEST variable just to change the default catalog. I want to set my default catalog from a DTMLMethod and I don't want to go to display some result screen after the change has been made. Currently I've modified the method to simply return after setting the default_catalog if REQUEST is None. However, I don't really like having custom Zope mods since the probability of losing them is high when upgrading. What is the process for making a request for a change to a particular Zope method? Thanks. James W. Howe mailto:jwh@allencreek.com Allen Creek Software, Inc. pgpkey: http://ic.net/~jwh/pgpkey.html Ann Arbor, MI 48103

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ZCatalog, import errors, and indexing errors
by R. David Murray 06 Mar '00

06 Mar '00

Well, I may have been foolhardy. Based on various comments on this list I did not think I would have any trouble importing a 60,000 record database into Zope and ZCataloging it. Having the records in Zope as objects made a lot more sense for this project than putting them into a backend RDBMS. The first problem I ran into was during the import. I wrote an external method that read the data from a tab delimited file and used the data to build ZClass instances. I tried to create them all in one folder in one transaction. This failed miserably at somewhere around 1500 records. I got an error about an 'frexp' call being out of range, somewhere in ZCatalog's BTree methods (my apologies for not having captured the exact error; maybe I can reproduce it once I've finished building my new test system). So I tried loading the records in batches, and at first that seemed to work. Then I got an out of memory error. After noticing that trying to view that directory in the management interface threw both my browser and Zope into fits, I decided to try loading the records into multiple folders. This also seemed to work. I used 1000 record batches. But occasionally I would get the frexp error. If I tried the load several times, it would eventually complete without error. Loading other batches in between tries seemed to help, but that may be an illusion. My load method ended up with the occasional short file, and I got this frexp error with batches as short as 300 records. So I think the error has something to do with the catalog machinery and not the batch size. So I finally got the database loaded, and everything seemed to be working. However, we have just discovered that certain keywords do not appear to be yeilding the expected results on searches. The ZClass is catalog aware, and there are a few fields being indexed. The one of concern is just called 'keywords'. Despite its name it is a text index, so that we can take advantage of the ability to do 'AND'ed searches. One more piece of info that may or may not be important. There are actually two ZClasses: the one holding the database records, and another class with a property of the same name (keywords). Instances of this second class get added by hand. Now we find that when we enter certain keywords (the examples we have found so far are 'well' and 'fire', which you probably don't need to know) on one of these by-hand ZClass instences, they are *not* found by a ZCatalog search on the keywords field index. Other words entered into the keywords field do cause the record to be found ('wells', for example). Now, I'm guessing no one is going to have an answer for me. What I'm hoping for is some tips for how to go about debugging this. Actually, what I'm really hoping is that someone from DC will view this as an important enough bug that they'll ask for a login on my system to check it out through <grin>. I have a gut level feeling that the frexp error and the index failure are related, so I also may try a total reload of the database, if someone can answer question (2) below. To sumarize, this experience has raised several questions in my mind: 1) what is the practical limit on the number of entries in a folder, and is there some way to get around this for instances where you want to use the ZODB as a database for a large number of records? 2) is there a practical limit on the number of changes that can be part of a transaction (eg: *should* I be able to add 60K objects in one transaction?) 3) what is the best way to do a massive data load? 4) how does one go about debugging ZCatalog? (I've read the debugger doc posted here, and I'll see if that is enough to allow me to get started on this) --RDM

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Re: [Zope-PTK] event ZClass
by Loren Stafford 06 Mar '00

06 Mar '00

I'm working on ZScheduler which implements basic scheduled events. It's not related to PTK. Discussion is on zope-dev(a)zope.org. I just got something functional running. If you like to play with fragile SW, check it out at http://www.zope.org/Members/lstaffor/ZScheduler Let me know whether it fits your needs. -- Loren ----- Original Message ----- From: Timothy Wilson <wilson(a)visi.com> To: <zope-ptk(a)zope.org> Sent: March 06, 2000 11:55 AM Subject: [Zope-PTK] event ZClass > Hi everybody, > > I remember that someone mentioned they were working on an event ZClass. Am > I remembering correctly? Is so, I'd love to hear how it's coming because > I'm very interested in something similar. > > -Tim > > -- > Tim Wilson | Visit Sibley online: | Check out: > Henry Sibley HS | http://www.isd197.k12.mn.us/ | http://www.zope.org/ > W. St. Paul, MN | | http://slashdot.org/ > wilson(a)visi.com | <dtml-var pithy_quote> | http://linux.com/ > > > _______________________________________________ > 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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Confused about catalog unique ID in ZScheduler
by Loren Stafford 06 Mar '00

06 Mar '00

Two questions really: 1. How do I get the uid from the catalog in a python product. Currently I have for event in self._catalog.searchResults( nextEventTime=DateTime(1), nextEventTime_usage='range:min', sort_on='nextEventTime' ): next_url = event.absolute_url next_time = event.nextEventTime #next_uid = event.uid break # just look at the first one return (next_uid, next_time, next_url) ...but that event.uid line isn't correct. 2. I need to add to ZScheduler the ability to delete a catalog entry if the Dispatcher gets an error when it tries to disarm an event. Is uid what I need in ZScheduler to subsequently do this? self.uncatalog_object(uid) My confusion here is knowing that uid is based on relative URL but knowing (vaguely) that relative URL is problematic in vurtual hosting environment (the very reason that ZScheduler catalogs absolute_url and uses it to identify the target ZEvent). Can someone clarify? -- Loren

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