July 1999 - Zope - Zope lists

RE: [Zope] Upgrading Zclasses
by Alexander Staubo 22 Jul '99

22 Jul '99

Well, the DCE UUID algorithm uses the NIC's MAC address, which is independent of the host name; host names tend to change, MAC addresses tend not to. The UUID algorithm also includes a guard against backward-moving clocks. -- Alexander Staubo http://www.mop.no/~alex/ "`Ford, you're turning into a penguin. Stop it.'" --Douglas Adams, _The Hitchhiker's Guide to the Galaxy_ >-----Original Message----- >From: Jim Fulton [mailto:jim@digicool.com] >Sent: 22. juli 1999 15:22 >To: Alexander Staubo >Cc: Zope Mailing List (E-mail); 'Rob Page' >Subject: Re: [Zope] Upgrading Zclasses > > >Alexander Staubo wrote: >> >> Sounds like UUIDS or GUIDs would have been an even better >identification >> scheme. > >The algorithm used by ZClasses is very similar to that used in other >GUID schemes. The algorithm uses a hash of location (ZClass URL) >and time. I think that the probability of collisions is similar between >the ZClass alogorithm and other schemes and the ZClass algorithm is >alot simpler. > >Jim > >-- >Jim Fulton mailto:jim@digicool.com Python Powered! >Technical Director (888) 344-4332 http://www.python.org >Digital Creations http://www.digicool.com http://www.zope.org > >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] Upgrading Zclasses
by Alexander Staubo 22 Jul '99

22 Jul '99

Sounds like UUIDS or GUIDs would have been an even better identification scheme. -- Alexander Staubo http://www.mop.no/~alex/ "`Ford, you're turning into a penguin. Stop it.'" --Douglas Adams, _The Hitchhiker's Guide to the Galaxy_ >-----Original Message----- >From: Rob Page [mailto:rob.page@digicool.com] >Sent: 22. juli 1999 15:00 >To: 'Itamar S.-T.' >Cc: 'zope(a)zope.org' >Subject: RE: [Zope] Upgrading Zclasses > > >> What happens if two different people create ZClasses with the >> same IDs? >> >> For example: >> Alice creates ZClass Foo. It gets an ID of 2. >> Bob creates ZClass Bar. It also gets an ID of 2. >> >> Bob imports Foo. Since its ID is already used, I assumes it >> gets assigned a >> new one, lets say 3. >> >> Alice changes Foo, and sends Bob the new Foo. When Bob >> overwrites the old >> Foo with the new, Zope has to know the Foo's id was changed >> to 3 from 2. (I >> admit to adding the second rhyme on purpose). > >:^) > >If two people create ZClasses with the same ID the scenario >you describe >will occur. However, the default class id (in the basic tab) is a hash >(MD5?) of the hostname and time. The odds of accidentally getting the >same class id (unless you change the computed default) are very small. > >--Rob > >_______________________________________________ >Zope maillist - Zope(a)zope.org >http://www.zope.org/mailman/listinfo/zope > >(To receive general Zope announcements, see: >http://www.zope.org/mailman/listinfo/zope-announce > >For developer-specific issues, zope-dev(a)zope.org - >http://www.zope.org/mailman/listinfo/zope-dev ) >

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RE: [Zope] Upgrading Zclasses
by Rob Page 22 Jul '99

22 Jul '99

> -----Original Message----- > From: Itamar S.-T. [mailto:itamars@ibm.net] > Sent: Thursday, July 22, 1999 7:06 AM > To: Zope-l > Subject: [Zope] Upgrading Zclasses > > > Let's say I create a ZClass and then distribute it to other > people, who then > use it in their website. If I make changes to the Zclass, > the instances get > automatically changed, but if the other people using the > Zclass want to have > my changes, ie. use the updated Zclass, how can they do so > and have their > instances use it too? I'll go WAAAY out on a limb here and explain what I think to be so (of course I only learned these details yesterday so ymmv). If anyone knows different please correct me. ZClasses have a unique_id that is generated when they are created. Caveat: older ZClasses didn't do this so you may need to add the id manually (I have no idea how to do this). Instances of this class get this id when they are created. If you distribute a ZClass definition and then upgrade it it will still have the same id. As a result, when you overwrite the new ZClass definition over the older one, it also will have the same class definition. Restarting Zope will cause the new ZClass definition to be loaded and the instances get the new behavior... Pretty cool... Okay Jim and Brian, let the roasting begin! :^) --Rob

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RE: [Zope] Upgrading Zclasses
by Rob Page 22 Jul '99

22 Jul '99

> What happens if two different people create ZClasses with the > same IDs? > > For example: > Alice creates ZClass Foo. It gets an ID of 2. > Bob creates ZClass Bar. It also gets an ID of 2. > > Bob imports Foo. Since its ID is already used, I assumes it > gets assigned a > new one, lets say 3. > > Alice changes Foo, and sends Bob the new Foo. When Bob > overwrites the old > Foo with the new, Zope has to know the Foo's id was changed > to 3 from 2. (I > admit to adding the second rhyme on purpose). :^) If two people create ZClasses with the same ID the scenario you describe will occur. However, the default class id (in the basic tab) is a hash (MD5?) of the hostname and time. The odds of accidentally getting the same class id (unless you change the computed default) are very small. --Rob

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Security quirk
by Toby Dickenson 22 Jul '99

22 Jul '99

I am seeing some unexplained differences between authorisation in these two DTML methods: Method A  Method B  When viewed by an anonymous user, A gives the Unauthorized exception that I was expecting, but B succeeds. This is the same in 1.10.3 and in alpha 3. I couldn't find anything specific in the documentation.... should authorisation be checked in these cases?

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dtml-var "fmt" question
by Jens Vagelpohl 22 Jul '99

22 Jul '99

hi everyone, maybe someone has done this before and could advise me: i want to format a floating point variable so it comes out using the european decimal point notation. so instead of 12.5 i would like it to say 12,5 etc. the DTML guide offers some nice built-in formats (like "dollars-and-cents"), i wonder if someone had an idea about maybe doing a "euros-and-cents" one, with the right decimal punctuation and a euro sign ;) Jens Vagelpohl P.S.: at this point i wonder why i ever wrote static HTML... :P

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RE: [Zope] Z PyGresql DA questions
by HCSCCS＠prudential.com.my 22 Jul '99

22 Jul '99

Thanks but I have one headache. The problem is pno isn't the primary key. The combination of pno and doctype field is the one. So the sql stmt only works if polno, doctype in doc <> polno,doctype in loan! Any ideas? ---------- From: Rob Page Sent: Wednesday, July 21, 1999 11:05 PM To: HCSCCS Cc: zope Subject: RE: [Zope] Z PyGresql DA questions MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.1960.3) Content-Type: text/plain > Hi. I'm building a loan system with Zap and I have a SQl statement > problem. Let's say I have 2 table: loan and doc > > Fields in doc: pno * > doctype * > docloc > ... > > Fields in loan: usrid * > pno * > doctype * > ... > Note: * means primary key > > What I want to query is how do I get all the pno and its > according type, > that doesn't exist in the loan table? This is to make sure that the > borrower does not select a document that had been loaned!!! > In other > words, all documents except those that are being borrowed. How 'bout: SELECT * from doc WHERE pno NOT IN (SELECT pno FROM loan) --Rob

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RE: [Zope] Bulk insert in Zope's ZPyGres
by HCSCCS＠prudential.com.my 22 Jul '99

22 Jul '99

Thanks. But how do use insert statements thru Z SQL Mtehod submitting it again? We will need to submit the web page a lot of times to get the variables across, wouldn't we? How do we address this problem ? Again, please reply to my personal mail also. ---------- From: "Phillip J. Eby" Sent: Wednesday, July 21, 1999 9:00 AM To: Paul Chung Chee Soong; zope Subject: Re: [Zope] Bulk insert in Zope's ZPyGresql Content-Type: text/plain; charset="us-ascii" X-Loop-Detect: 1 At 09:18 AM 7/21/99, Paul Chung Chee Soong wrote: >Hi. I'm beeen using Zope-1.10.3-src, Zap-1.10, RedHat 5.2 and lately >ZPyGresql Database Adaptor. Okay, the problem is can I do the aboved. For >instance, I put a few checkboxes (the amount is dynamic) on the page. >Then the user will click on the items they want to borrow and press the >submit button. After that, the next page will insert all this entries >into records in a postgres table. > Just make the checkbox field a :list field, and have your SQL method do an  block that loops over it to create a series of INSERT statements in one batch.

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Upgrading Zclasses
by Itamar S.-T. 22 Jul '99

22 Jul '99

Let's say I create a ZClass and then distribute it to other people, who then use it in their website. If I make changes to the Zclass, the instances get automatically changed, but if the other people using the Zclass want to have my changes, ie. use the updated Zclass, how can they do so and have their instances use it too? -- Itamar - itamars(a)ibm.net ----------------------------o----------------------------------------------o Sealingwax Greeting Cards | Trust? Ha! The US dollar is backed by ICBMs! | http://www.sealingwax.com | --Anonymous Coward, Slashdot |

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RE: [Zope] Problem with file upload
by Rob Page 22 Jul '99

22 Jul '99

> I have some problem with file upload with python and Zope. > Can someone help me ? > > I just want to import a gif or jpg file from a client to Zope ! Can you provide some more details? Are you trying to upload through a browser or from a Python client. What is the error you are getting and on what platform are you running (incl browser)? --Rob

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