April 2000 - Zope - Zope lists

Re: [Zope] using zope for broadcast e-mail messages...
by Anthony Baxter 23 Nov '00

23 Nov '00

>>> chas wrote > Zope's dtml-sendmail tag is excellent - it makes sending > e-mail a breeze. It reminds me of a similar tag that > Cold Fusion added and which I've noticed many sites use > for sending out customized newsletters (the "Allaire > ColdFusion Application Server" header being the giveaway). > > > Now, doing the same in Zope, I can loop over the user > profiles in our database to extract name, e-mail, and > even customize the content of the newsletter as follows : > > > <dtml-in ZSQL_Select_User_Profiles> > >  > To: <dtml-var firstname> <<dtml-var email>> > From: robot <robot(a)ourdomain.com> > Subject: <dtml-var random_inanity> > > Dear <dtml-var firstname>, > > blah blah content (also dependent on his/her likes/preferences) > >  > > </dtml-in> > > > Nothing groundbreaking so far. But the question then is : how > is this going to work if the user database numbers 200,000+ ? > It will take almost half a day to complete and this can't be > done in one form-submission or page load ! Why not use ZClient to make the request to do the mailout? It can just happily sit there for half a day (or whatever) chugging along, without screwing up if your browser goes away. Anthony -- Anthony Baxter <anthony(a)interlink.com.au> It's never too late to have a happy childhood.

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99.9% CPU usage (0.1% brain usage)
by Kevin Smith 26 Jun '00

26 Jun '00

Hi there, For some reason Zope would suddenly hang and it's thread would consume 99.9% of CPU usage. The first time this happened the problem magically disappeared after a complete reinstall. Here's what happened while casually throwing bannerexchange code into the default DTML document. standard_html_footer </td> </tr> </table> <dtml-var bannerexchange> </body> </html> bannerexchange <dtml-var standard_html_header> <h2><dtml-var title_or_id></h2> <p>  </p> <dtml-var standard_html_footer> <---- Oops! I'm on Zope 2.1.6, do future version prevent me from making accidental infinite loops like this? Kevin Smith BTW: I get exponentially more done with Zope every day. Thanks for Zope.

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Previewing Temporary Images
by Chris Crownhart 30 May '00

30 May '00

I am writing an HTML form that is using the type=file attribute to collect an image from the user. I am also collecting other information and then formatting it on a page in a preview mode. I would like to allow the user to preview their data, with an image, before they elect to save it (in Zope). The problem, I think, is that the IMG tag needs a physical file to point to in order to render the image. Given that the image object is of type FileUpload, once the user presses the submit button, is there a way to display that FileUpload Image without actually saving it in Zope? Thanks for any suggestions, Chris

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<code> tag?
by Mike Winter 24 May '00

24 May '00

Hi, just a quick question: how do you get Zope to display DTML without evaluating it? -- Mike Winter | mfw127(a)mail.usask.ca U. of S: 966-4759 TR Labs: 668-9323

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FYI: Zope Weekly News
by Mike Pelletier 23 May '00

23 May '00

G'day, Zope Weekly News is a digest of some of the useful and interesting events which have occurred on the various Zope mailing lists and the Zope.org site. It is published each Wednesday evening. New Products and Announcements * Paul Everitt announces Sybase support in a joint press release. http://lists.zope.org/pipermail/zope/1999-November/013946.html http://www.digicool.com/News/Sybase * "Zen" released ZRadius, a product which allows you to authenticate web users via the Radius authentication protocol. http://www.zope.org/Members/Zen/ZRadius * Anthony Pfrunder announces VisualZope 0.1a. From his web page: Basically, the "goal" of VZ is to provide a SIMPLE visual editing system for graphic designers which works cross-browser and takes advantage of the acquisition and role systems within Zope. What follows is a brief description of the components which make up the final VZ system (probably more accurate than previous posts). http://163.182.196.200/zwiki/VisualZope * Jeff Sheldon has started a weblog of his experiences with Zope. Jeff Sheldon is new to Zope, and is not a professional programmer. His weblog is a valuable resource to those also starting out with Zope. http://weblogs.userland.com/zopeNewbies/stories/storyReader$0 Updates * Zope 2.1.0 beta 2 has been released. This release includes fixes for issues found in beta 1, an updated load_site.py script and Martijn Pieters' patches to implement try/except/else and try/finally in DTML. Unless something major comes up, this will be the final beta before 2.1.0 final. http://www.zope.org/Products/Zope/2.1.0b2/ * "4am" has submitted an update to his PythonMethod product. It allows methods, written in Python, to be created via the Zope web management interface. http://www.zope.org/Members/4am/PythonMethod * "Drew" contributed an update to his Photo product. It generates thumbnail views of images at the user's preferred size. Requires PIL. http://www.zope.org/Members/Drew/Photo * Itamar Shtull-Trauring announced ZCache v0.2. ZCache is a Python Product which allows you to cache expensive methods, taking strain off your server. It also generates 'Last-Modified' headers, aiding browser and proxy caches. http://lists.zope.org/pipermail/zope/1999-November/014115.html http://www.zope.org/Members/itamar/ZCache Zope.org items * "Zen" submitted a tip he picked up from Michel Pelletier. He explains how volatile attributes work, and how to populate them when your object is loaded from the database. Volatile attributes are attributes which do not get written to the database, and are good for data which changes frequently. http://www.zope.org/Members/Zen/tips/VolatileAttributes * "AlexR" submitted a How-To detailing the use of the DTML entity syntax. "DTML entities" are chunks of DTML which look like this: "&dtml-title_or_id;" http://www.zope.org/Members/AlexR/EntitySyntax Notable Discussions * DTML is a HUGE topic this week. Discussions spill across several lists. A very good job is done of identifying DTML's weak points. Many hold that the difficulty in using DTML comes from it's roots as a reporting language-- it isn't supposed to be used for logic. The problem is, there isn't yet an easy replacement for DTML as a programming language. Python Methods are cited as an excellent start on providing a means of moving logic out of DTML. Christopher Petrilli mentions that DC is looking at grooming Python Methods for inclusion in Zope. Others feel that reporting vs. programming is a forced distinction, and that it is awkward to have to use two different solutions. The claim that generating HTML is actually a rather complex task, and the powerful but ugly features of DTML are a necessary evil. DTML is compared to Perl! <gasp!> Otherwise, lots of very useful tips for using DTML are revealed. An excellent read for DTML beginners and wizards alike. http://lists.zope.org/pipermail/zope/1999-November/013710.html http://lists.zope.org/pipermail/zope-dev/1999-November/002088.html http://lists.zope.org/pipermail/zope-dev/1999-November/002102.html * Darcy Clark alerts the list of Jon Udell's latest article mentioning Zope. Jon's article discusses the ease of using Zope with Windows databases, the pain of using it with Unix databases, cheers ODBC, and jeers lack of a similar magic bullet for Unix. The thread then continues to discuss the relative merits of various free databases and using them with Zope. http://www.byte.com/column/BYT19991104S0001 http://lists.zope.org/pipermail/zope/1999-November/013711.html Also, Karl Fast does an excellent job of summarising the thread, generating more sage comments. http://lists.zope.org/pipermail/zope/1999-November/013762.html http://lists.zope.org/pipermail/zope/1999-November/013812.html http://lists.zope.org/pipermail/zope/1999-November/013813.html http://lists.zope.org/pipermail/zope/1999-November/013840.html * Francois-Regis CHALAOUX posed a question about using Zope with virtual hosting. Several useful responses were generated. http://lists.zope.org/pipermail/zope/1999-November/013678.html http://lists.zope.org/pipermail/zope/1999-November/013688.html * Ben Galbraith submitted a comparison of Zope and Cold Fusion and solicited comments. Some of the usual suspects offer theirs. http://lists.zope.org/pipermail/zope/1999-November/013730.html * Otto Hammersmith started a thread about Zope and security. In it, he speaks of some of the security pitfalls that unsuspecting Zope users could experience. Brian Lloyd submits some solutions. http://lists.zope.org/pipermail/zope/1999-November/013779.html * Paul Everitt wrote in to remind us that there is a zope-dev(a)zope.org list for technical discussions. A brisk discussion developed to debate what constituted a technical discussion. http://lists.zope.org/pipermail/zope/1999-November/013796.html * Theodore Patrick launched a lengthy thread with questions about the effect of threading in Zope. A number of folks from Digital Creations provide answers. The discussion moves on with high volume and content to the topics of benchmarking and performance tuning Zope. http://lists.zope.org/pipermail/zope/1999-November/013808.html * Farzad Farid revives the uncacheable image thread. Because Acquisition can lead to different URLs being generated for images when viewed from different locations, it makes caching difficult and can generate excessive traffic. Others offer advice to solve this problem. http://lists.zope.org/pipermail/zope/1999-November/014021.html * David Harrison asks zope-dev how to return an image generated on-the-fly by an External Method. Answers found. http://lists.zope.org/pipermail/zope-dev/1999-November/002107.html Mike Pelletier

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Ann: Squishdot 0.3.4 Released
by Chris Withers 19 May '00

19 May '00

Squishdot 0.3.4 is now available from http://www.zope.org/Members/chrisw/Squishdot/ It fixes the following problems: - Moderators no longer need the 'manager' role to approve articles. - The Suggested Author, Email Address, etc, no longer vanish when SiteAccess is used for virtual hosting. There are some other small changes and improvements. Lookout for Squishdot 0.4.0 in the (not too distant ;-) future which will hopefully use the new Zope indexing system. If you run into problems, remember Squishdot has a mailing list at eGroups and a bug collector on SourceForge.

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VNU Net: Python 3000 not backwards compatible, warns creator
by Yong Heng Teo 16 May '00

16 May '00

Hi, I have learning Zope for 6 months and have been following the mailling list. I come across the following news : Python 3000 will not be backwards compatible. Question : How will it affects Zope ? Regards, Yong Heng http://linuxtoday.com/stories/19062.html http://lwn.net "Python 3000 to be Complete Rewrite. Linux Today reports a warning by Guido van Rossum that Python 3000 will not be backwards compatible with Python 1.x. Guido plans to develop 3000 in tandem with 1.7 later this year. (1.6 is due by summer.) "'Python 3000 is a monumental effort - all the code will be rewritten and the documentation revised. This is my one chance to reimplement Python and fix its efficiency problems. But how incompatible it will be is a very big open question and I don't have a concrete answer,' he said." " __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com

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Zope's scalability across multiple web servers
by Bostick, Aaron 14 May '00

14 May '00

I am in the process of designing a web site that will handle the load of a nationally advertised web site. I am considering using Zope over Pervavsive's Tango2000 or Vignette's StoryServer as an application server. What I would like to know is if there are any easy ways to replicate the ZODB information across web servers if I am running a web farm? In other words, I plan to have multiple identical web servers sitting behind a load balancing appliance so that incoming requests can be sent to any of the web servers. Obviously, the web servers must contain the same data for this to be of any use. If I plan to run a web server and the zope engine on each "web server", how can i replicate changes to all my servers to keep them synced. Would something as simple as a recursive copy work for this? This is not something that will have to be done in real time. Something simple like a batch job would suffice. Other than the database content, the HTML stuff will remain relatively static. Please excuse my ignorance on Zope. I haven't had the chance to set it up yet and am still in a preliminary design phase. Thanks for any helpful hints regarding this matter! Aaron Bostick Exodus Communications

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A nice problem with url_quote_plus
by Nbk 12 May '00

12 May '00

Hi. I have the folowing code in one of my DTML method's: <dtml-call "RESPONSE.redirect(_.string.join([url,query],''))"> 'url' and 'query' are two variables passed by the REQUEST. This work's just fine, but with some minor :-) problems in my case. If i have a 'query' with some spaces, the RESPONSE.redirect causes an obvious http error. So, i want to replace some characters of my 'query' variable. And guess what? <dtml-var url url_quote_plus> gives me the right string. How do i do an "quote_plus" ( like in python urllib module ) in Zope, without using an External Method? BTW, i've used an python method, but with no luck ( i can't make a simple "import urllib"). TIA, @886, Nbk ( Just believe, Zope source code is the best place to find up-to-date documentation! ) P.S. - I've looked up for the solution in www.google.com, www.egroups.com, lists.zope.org, www.zope.org, www.python.org, and some other resources. I had find some interesting ideas, but none of them are usefull to this problem. :-)

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Fix for SiteAccess bug affecting ZCatalog users
by Evan Simpson 11 May '00

11 May '00

There's a subtle bug in current and older versions of SiteAccess which can cause ZCatalog and dependent Products to fail. If you use an Access Rule in your root folder which alters REQUEST.path (for virtual hosting purposes, for example) then all ZCatalogs will return incorrect objects. In Products/SiteAccess/ChangeBehaviors.py, delete lines 68 and 69, or comment them out so that they look like: #if allow_btr: self.before_traverse(object, response) #entry_name = '' This ought to fix the problem. Please let me know if it doesn't. If nobody says anything, this will become SiteAccess v0.2.1 Also, a word of warning: Since ZCatalog doesn't store information (such as the request's hostname and port) used to determine object access paths under virtual hosting, you should avoid adding objects to a Catalog via one virtual host (or raw access) and retrieving them via another. Cheers, Evan @ 4-am

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