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restrictedTraverse doesn't give the good container.
by Pascal Samuzeau 13 Feb '04

13 Feb '04

Hi, Today, I have this situation: Under my root Zope Site, I have this hierachy: - FolderA ---FolderB ----FolderC -----FolderC What is interesting is that a folder named "FolderC" appears under another folder named with the same name. Assuming the path is the good one (path=.../.../FolderB) I try : herenow = context.restrictedTraverse(path+'/FolderC') -> OK herenow = herenow.restrictedTraverse(path+'/FolderC') -> OK Now I just delete the last FolderC, I have: - FolderA ---FolderB ----FolderC I try : herenow = context.restrictedTraverse(path+'/FolderC') -> OK herenow = herenow.restrictedTraverse(path+'/FolderC') -> OK BUT here I'm just not where I think to be, just because of the acquisition !!! I have no time to have a look on this, but anyone have seen this problem and resolved it? Sincerily PS -------------------------------------------------- Oreka ! Nous sommes l'internet moins cher ! Surfez 25% moins cher avec http://www.oreka.com

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Put an adapted object in context
by Santi Camps 13 Feb '04

13 Feb '04

Hi all, Following your instructions and seeing Skin Product code, I've been able to write a simple way to register Apdaters in my applications that are applied to specific meta_type objects during publishing. This is now working fine. I can write an Adapter in my application and say "use this adapter for all objects of meta_type 'Folder'". The adapter to apply of the same object may change depending of user and the application he is using. My problem is that the adapter object, and also the adapted object contained in it, are out of publisher context or something like this. For instance, absolute_url() methods doesn't work becouse REQUEST is not defined. If I add REQUEST manually to the object, the absolute_url returns the object Id, but not the entire path. I can inspect absolute_url code and try to provide needed information to make work, but I'm sure that somewhere should be a method to put my object in the current publishing context. Anybody knows about this? Thanks a lot for your help. -- Santi Camps http://zetadb.sourceforge.net

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RE: [Zope-dev] How to make Zope fail nicely under high load?
by Bjorn Stabell 13 Feb '04

13 Feb '04

Erik: > using the _v_ variables won't work for this since different threads > won't agree on who was latest. Its definitely a bad idea to > do queries > for these three data points. What about putting them in the > temp_folder then you can still use ZEO with a bunch of clients that > will all share the same data but you don't need to write the > values to > disk every time they change. Even putting them in a normal ZODB > storage would be a _lot_ faster than doing a query. You're right, _v_ wouldn't work. So with temp_folder (TemporaryStorage) there is basically no need for the SharedResource product anymore? For ZEO, my understanding is that we would still have to store the values in the ZODB, though. Regards, -- Bjorn

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RE: [Zope-dev] How to make Zope fail nicely under high load?
by Bjorn Stabell 13 Feb '04

13 Feb '04

Toby wrote: > > One of the optimization we're thinking of is storing results of > > ZCatalog searches (e.g., number of replies to postings) in volatile > > variables so we don't have to run the catalog search at all. We'd > > like to use memory space shared between threads for this. > > Using ZEO would require us to store this in the ZODB. > > Storing that in ZODB would be a bad idea. Theres no reason to > think that this cache would be faster than ZCatalog. > > I dont see why you would be *required* to store in ZODB... > just dont share your cache between publisher threads on different > Zope instances. > > (my apologies if this is obvious) Okay, for example, since it's a BBS we need to have quick access to: the latest poster the latest posting the latest registered member All of these are complex queries (in the case of the latest registered member it's not even a query but a brute-force search). What I think most ASP/PHP boards do is that they store these values in the database instead of querying for them all the time. Since many of these can be found through queries, they don't really need persistent storage, but updates need to be seen by all threads; thus the requirement for ZODB if we use ZEO, but the possibility to use (even faster) shared memory if we don't use ZEO. In effect we want to do something like this: def getLatestPoster(self): if not hasattr(self, '_v_latestPoster'): self._v_latestPoster = whatever_query() return self._v_latestPoster return self._v_latestPoster def setLatestPoster(self, poster): self._v_latestPoster = poster But instead of having thread-local variables we wanted to use Dieter Maurer's SharedResource in order to share the cache between threads: http://www.dieter.handshake.de/pyprojects/zope/SharedResource.html Regards, -- Bjorn

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HELP NEEDED!!!
by Rajesh s shiggaon 12 Feb '04

12 Feb '04

Hi everyone, I am getting an error Error Type: OperationalError Error Value: (1205, 'Lock wait timeout exceeded; Try restarting transaction') i am trying to insert vaules into 2 tables (MYSQL). In the first table i make a new record and get the unique id for tht using THE MYSQL FUNCTION . but when it try to insert a record for the next table for which i am using this id....it gives an error. but when i try to give a static id for the second table....it is not giving any error. so i guess it is bcoz of transactions of zope... how to overcome this problem...any sugesstions are welcome!!!!! Regards, Rajesh Rajesh Shiggaon

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Persistence Module Confustion (fwd)
by D. Bickle 12 Feb '04

12 Feb '04

I am trying to import the MailHost module that has dependencies with the Persistence package. The interpreter complains that it cannot load the Persistence modules and when I examine the package there is no content or modules. How can I fix my code to resolve these dependencies? Have the Persistence modules been deprecated? Thanks,

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Adapters in Zope 2
by Santi Camps 12 Feb '04

12 Feb '04

Hi all, I know that adaptors are introduced in zope3 but, anybody knows if this technique can be used in zope2 ? I've been trying to add some extra functionallity to a Folder object without inheriting, but I'm not able to make it work. To maintain the adapted object publishable I've rewrited __getattr__, but then some extra problems appears. Anybody knows if there is a way to use adapters in zope2 ? Or, if not, there is some other way to add functionallity on-the-fly, without inheriting ? Thanks in advance -- Santi Camps http://zetadb.sourceforge.net

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Re: [Zope-dev] Re: How to make Zope fail nicely under high load?
by Peter Sabaini 12 Feb '04

12 Feb '04

Bjorn Stabell wrote: > Hi Peter, > > >>I think I did find some sort of knob for this >> >>For Apache 2.0, mod_cache, dir. CacheIgnoreCacheControl could be used >>for this >>http://httpd.apache.org/docs-2.0/mod/mod_cache.html >> >>For Apache 1.3 mod_proxy, dir. CacheMaxExpire could do >>http://httpd.apache.org/docs/mod/mod_proxy.html#cachemaxexpire > > > I think this will force Apache to cache content no matter if the > content's headers have cache control settings, but will it force Apache > to not re-request the content if the browser forces a reload? > (Ctrl-refresh in IE.) This really should be tested, but as far as I can remember it did serve from cache rather than rerequest. Its been some time since I did this (and at another company) and unfortunately I cant remember this too clearly... From the 'CacheIgnoreCacheControl' at least it does sound like it would ignore the spec and serve cached content though. cheers, peter.

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RE: [Zope-dev] How to make Zope fail nicely under high load?
by Bjorn Stabell 12 Feb '04

12 Feb '04

Jan-Wijbrand wrote: [...] > You are able to store *and* share data over ZEO Clients in a > TemporaryStorage by making the ZSS serve this > TemporaryStorage to its ZCs. You could mount this storage as > temp_folder I guess, but any other mount point would work too. Coooool.... :) > Not sure, but I'd expect so, whether this has significant > perfomance advantages over a 'normal' ZODB served by the ZSS. Probably, and it's no-packing as well. Very nice. We'll definitely use this then. Bye, -- Bjorn

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RE: [Zope-dev] How to make Zope fail nicely under high load?
by Bjorn Stabell 12 Feb '04

12 Feb '04

Jamie writes: > Lennart Regebro wrote: > > OK, you get the problem that images may not load even if > the main page > > does, but is that really worse for the end user than not getting > > anything? > > As I've been saying, if you do that, they will reload > repeatedly making the problem worse. If the images are fluf, > and the user knows they are fluf, then *maybe* they won't > reload, and your pages will simply appear ugly. But then you > have to ask yourself, why am I sending fluf images that > degrades the overall user experience of my application? > Clearly there's more optimization that could be done to your > application. If you run Apache as a caching reverse proxy (caching surrogate server) then images will be served from Apache. Only the dynamic HTML pages are served from Zope, so having them fail without regards to sessions is relatively okay. Images and other static content are almost guaranteed to load correctly, and if they didn't, a straight reload from the client will not reload cached images. Regards, -- Bjorn

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