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restoring deleted data
by Back, Elyssa 03 Mar '03

03 Mar '03

Good morning, I am Zope newbie who used the program in December to build a medium-sized site. I installed Zope on my work computer and did all my development there. When I came in last week, I found that my system administrator had completely deleted my version of zope. Everything was gone - the server, the installation program, the supporting software, ect.... I was just wondering if there was a way to recover any of my code or to restore the site, without re-doing everything. If there is documentation about this on one of the zope sites, feel free to point me to it. Thanks so much! Elyssa ************** It is impossible for us simply to serve soup and provide shelter without crying out that homelessness is a gross injustice and an indictment of a society that has so much and yet will not make available to all persons the basic necessities of food and housing. -Ed Loring, The Open Door Community, Atlanta

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RE: [Zope] Help Needed - Case for Zope
by sean.upton＠uniontrib.com 03 Mar '03

03 Mar '03

Forgive the generality of this comment, but I think one of the biggest things going for Zope is that it takes some hard integration problems and makes them simple. - ZEO makes object persistence cluster, and without really needing to do much to your applications (other than have good conflict-handling code in your applications to deal with increased storage write latency for the network, and handling cache invalidation mechanisms). So for the most part, clustered persistent objects allow things like shared sessioning across your cluster to just work. Scaling becomes less of a development issue and more of an integration/sysadmin issue, like it should be. I'll go out on a limb to say that Java is going to make you work harder to not only get close-to-transparent object persistence, but making that scale and cluster will be harder, and certainly you will be tied down to one particular ODB or serialization/storage framework vendor; ZODB is more open and more-or-less a standard for Python folks. ZODB makes transactions easy too. - Have you showed your management some of John Udell's latest InfoWorld columns? ("Shipping the Prototype" and "Refactoring the Enterprise")? http://www.infoworld.com/article/03/02/06/06stratdev_1.html http://www.infoworld.com/article/03/02/13/07stratdev_1.html - The Plone folks have plugged in their 1.0 press release that they support the first "industry standard templating language" (paraphrase) in Zope Page Templates. Since there are implementations of PT/TAL in other languages now, you could argue that for the presentation layer, you get something cleaner and more standardized than the popular (but platform specific) JSP type solution. - Make the case for Python; Zope naturally follows. One ROI factor for the suits could be explained in terms of lower post-project "is done" expenses (and therefore less risk), and that the language will enable your project to be maintained without high-cost in the long term, which decreases (a) the risk of scrapping the project 2 years down the line (because you can adapt easier), and (b) the risk that you will need to spend big $$ on major changes. Python lends itself to the "embrace change as inevitable" school of thought, and gives you something easier to manage changes in the system with. I think Udell's two articles go far to make this plug for "scripting the enterprise." Plug Python's use for Star Wars at ILM, Google, etc. I would also argue that Python makes it easier to write code in terms of your application, rather than make your business fit your technology or spend most of your time writing "bridge" code to make the two connect. See http://www.python-in-business.org/success for case-study type blips as to folks using Python. - Scalability: plug ZODB's storage-agnosticism to your management folks. You can use FileStorage, you can use BerkeleyDB storage, you can use DirectoryStorage (which will scale quite well, has tools for incremental backup and replication, and you can also use standard Unix tools too - works quite well for high-availability clustering), etc. On top of various object storage mechanisms, there is now a great mapping storage in AdaptableStorage, which allows you to write plugins to serialize object data to pretty much any mechanism you could think of (RDB, XML, LDAP, etc). This flexibility (with mostly free, easily available, vendor-agnostic software) is likely to be better and cheaper than what you might find in the Java world, where these things are less standardized, and more vendor-specific. Personally, I think the lower-costs, lower-risk, more flexibility arguments go pretty far. Java, as a popular platform is a low-risk platform, but it does this by moving the risk to the application (forcing you to deal with object persistence or serialization, transactions, sessions, etc, choose competing implementations of 3rd party technology - batteries not included) and making the developer compensate to keep the risk low, but this makes costs high. Zope, like Python has batteries included for a lot of things that are traditionally application-developer's problems, and removes some of the complexity away from having to do it yourself. Java's popularity, on the other hand, encourages choice, but also forces it on you as well, by playing to the hands of multiple vendors for app servers, object database technology, etc. Zope's integrated nature makes it easier to get started quickly without costly vendor or 3rd party technology commitments that may turn out to be a poor match. Python is less popular, but decreases the risks of your project, which ultimately is what really matters much more than the platform. I hope this is somehow helpful. Sean -----Original Message----- From: Samir Mishra [mailto:SamirMishra@cbuae.gov.ae] Sent: Sunday, March 02, 2003 1:08 AM To: 'zope(a)zope.org' Subject: RE: [Zope] Help Needed - Case for Zope Thanks everyone. Any Project managers out there with something to add with regard to comparison between speed of implementation for Zove vs. other products? Personally, I place maintainability and transitioning skills as my top priority, and elegance of code comes last. Speed (e.g., of the server) is a non-issue because one can always allocate better hardware for this since it's a mere commodity now, intellectual capital is always at a premium. And that's why I like Zope :) But I still have to sell the concept to managers who only hear "Java" & "JSP" from software vendors and so are most familiar with these technologies. Samir. -----Original Message----- From: Paul Browning [mailto:paul.browning@bristol.ac.uk] Sent: Sunday, March 02, 2003 11:58 To: 'zope(a)zope.org' Cc: Samir Mishra Subject: Re: [Zope] Help Needed - Case for Zope --On 01 March 2003 21:52 +0100 Dieter Maurer <dieter(a)handshake.de> wrote: > Samir Mishra wrote at 2003-3-1 14:26 +0400: > > My manager has requested comments on whether Zope "performs like a > dog". I'm > doing some digging around at the moment, but, in the > meantime, if anyone has > any links to recommend, benchmarks, > experiences to share, that I can use to > counter his 'assertion', it > would be much appreciated. > One way of getting Zope "run like a bow-legged terrier on sleeping pills" (Pieters, M., pers. comm.) is to use multi-processor Solaris without paying attention to the threading issues (see <http://www.zope.org/Members/glpb/solaris>). If you're starting from a clean sheet it's probably best to avoid Solaris. Paul -- The Library, Tyndall Avenue, Univ. of Bristol, Bristol, BS8 1TJ, UK E-mail: paul.browning(a)bristol.ac.uk URL: http://www.bris.ac.uk/ _______________________________________________ Zope maillist - Zope(a)zope.org http://mail.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://mail.zope.org/mailman/listinfo/zope-announce http://mail.zope.org/mailman/listinfo/zope-dev )

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Adaptable Storage Problem
by Andrew Veitch 03 Mar '03

03 Mar '03

I've got a problem with AdaptableStorage. If I set up a folder with AdaptableStorage I can add a CMF site to it but not a Plone site. I get: Traceback (innermost last): Module ZPublisher.Publish, line 102, in publish Module Zope, line 188, in commit Module ZODB.Transaction, line 222, in commit Module ZODB.Transaction, line 195, in commit Module ZODB.Transaction, line 256, in _commit_objects Module Products.AdaptableStorage.zodb.ASConnection, line 247, in commit Module Products.AdaptableStorage.mapper.ObjectSerializer, line 87, in serialize Module Products.AdaptableStorage.zodb.RemainingState, line 107, in serialize RuntimeError: Unable to pickle the '_catalog' attribute, <Catalog instance at 99526d0>, of <CatalogTool instance at 995d650> at ('/fs/test2/portal_catalog',). Cannot pickle <extension class Acquisition.ImplicitAcquirerWrapper at 40233ca0> objects. I don't understand how a portal_catalog won't pickle with AdaptableStorage but will with the ZODB. Thanks!

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ZODB Conflict errors
by Mike Heath 03 Mar '03

03 Mar '03

We're getting repeated ZODB conflict errors. They seam to only be occurring using frames when we have multiple users accessing the page at the same time. What is causing this? We're not doing any modifications to objects in the Zope database. Thanks, Mike Heath Terrapin Technologies, Inc.

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RE: [Zope] Re: How to run periodic processes - How to set Mail Ho st
by sean.upton＠uniontrib.com 03 Mar '03

03 Mar '03

I like cron, but not in combination with wget. I have found this (poking methods via http) to be problematic for me in the past with automated tasks, and have mostly switched over my processes to using out-of-process temporary ZEO-enabled Zope.app() instances in python modules executed by cron jobs. More info on my comparitive thoughts wget vs. Zope.app(), and example code: http://article.gmane.org/gmane.comp.web.zope.plone.user/2490 http://mail.zope.org/pipermail/zope/2003-February/131882.html Sean -----Original Message----- From: Josef Meile [mailto:jmeile@hotmail.com] Sent: Monday, March 03, 2003 11:23 AM To: zope(a)zope.org Subject: [Zope] Re: How to run periodic processes - How to set Mail Host > [Juan Emilio Drault wrote (juan@l...) on 3/3/03 10:05 AM] > > hi > > > How to run periodic processes inside Zope? > > I need it to run a process that sends E-mail every hour. > > you can use the XRON product but a better solution would be to use Cron > (Unix/Linux). I would also recommend you Cron. Once I used XCron and my system crashed everytime without finishing the XCron Method (It wasn't a Xron issue, but it affected the XCron Schedule). When Zope tried to restart, it tried to excecute the XCron Method again, so I got another email. It did it till I opened my email box (I got 500 emails). With Cron and wget this won't happen because unix/linux finish the excecution of the method without caring if it whether crashes or not. Regards, Josef _______________________________________________ Zope maillist - Zope(a)zope.org http://mail.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://mail.zope.org/mailman/listinfo/zope-announce http://mail.zope.org/mailman/listinfo/zope-dev )

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Re: How to run periodic processes - How to set Mail Host
by Josef Meile 03 Mar '03

03 Mar '03

> [Juan Emilio Drault wrote (juan@l...) on 3/3/03 10:05 AM] > > hi > > > How to run periodic processes inside Zope? > > I need it to run a process that sends E-mail every hour. > > you can use the XRON product but a better solution would be to use Cron > (Unix/Linux). I would also recommend you Cron. Once I used XCron and my system crashed everytime without finishing the XCron Method (It wasn't a Xron issue, but it affected the XCron Schedule). When Zope tried to restart, it tried to excecute the XCron Method again, so I got another email. It did it till I opened my email box (I got 500 emails). With Cron and wget this won't happen because unix/linux finish the excecution of the method without caring if it whether crashes or not. Regards, Josef

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VideoCapture module fails under Zope on Win32
by Tim 03 Mar '03

03 Mar '03

I've been playing with the python VideoCapture webcam module (http://videocapture.sourceforge.net/) and thought: wouldn't it be nice to wrap this in a Zope product! Yes, yes it would, I agreed with myself. Webcam controllable directly from Zope... Unfortunately I quickly seem to have hit a hurdle I can not get over. The VideoCapture module can not seem to open the device when running under Zope. The code works perfectly fine, using Zope's python version, when run from the command line outside of Zope... but inside Zope the identical (cut/paste) code always fails. The error message returned by the vidcap.pyd when trying to connect to the camera device is generic, so I can't see what specifically the problem is (if the windows error code is any more specific). I have the source, of course, but I'm not a c++ person so have no compiler. Anyhow it seems doubtful I'd be able to get around whatever the problem is. I'm just wondering if anyone might be able to enlighten me on possible reasons for this behaviour. I think vaguely recall that Zope on Windows runs at some sort of lowered privileges (but i could remember incorrectly; I don't know how these sorts of things work on Win32). Could this be the cause? How might one get around this, if so? -- Tim Middleton | Cain Gang Ltd | I have lived through whole tragedies x(a)veX.net | www.Vex.Net | without speaking a word. --Dost. (GC)

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Simple Persistent Cookie
by Luis Cortes 03 Mar '03

03 Mar '03

How do I create one with Zope, easily? How do I include the expires, domain, etc? Thanks ahead of time, Luis.

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Web mail & web chat
by Marc Burgauer 03 Mar '03

03 Mar '03

Hi I am looking for a Zope-based interface to offer web mail and real-time chat for a potential customer who intends to run a public web-based service. The average user will not be highly computer literate. (E.g. We expect many not even to have an e-mail account.) Web Mail -------- The only "serious" product I have found is: http://www.zope.org/Members/maraf/WebMail It requires an IMAP server, currently we're still only doing POP3. Also this product is in French, it seems. - If anybody is using this product, can you share some experiences? + stability + scale (number of users, etc.) + How does it integrate with acl_users? + Willing to share English graphics and templates? - Has anybody experiences with other products? I am considering to offer @Mail, which looks impressive and is OK in price, but it does not tie into Zope at all. (Or has somebody done this?) I mainly worried about the administration effort of keeping usernames and passwords in sync. Web Chat -------- I found this product: http://www.zope.org/Members/jwashin/ZRTChat Looks OK but is labeled as development. - If anybody is using this product, can you share some experiences? + stability + scale (number of users, etc.) - Has anybody experiences with other products? Cheers Marc

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Properties
by Jens JB. Bjerre 03 Mar '03

03 Mar '03

Hi Is there anyway how I can test, if an object (of any kind) has a special property.? Regards Jens

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