Re: [Zope-dev] Return variables from a DTML Method
[EMAIL PROTECTED] asked:
>
> I want to change some ZClass properties by getting return results
> from a DTML Method. Something like this: "myzclass.propertysheets.get('Basic').manage_changeProperties(dtmlM
> eth(this(),_))">. How do I get the dtmlMeth to return a Mapping?
> (or should I be doing this a different way?)
You *could* return a dictionary from a DTML method:
DTML Method 'return_dict'::
Foo:
Bar:
but I can't imaging wanting to. Try to rearrange your
stuff so that the code generating the mapping can call
'manage_changeProperties()' its own self, or else move
it to PythonScripts/PythonMethods/ExternalMethods/a Product;
you'll be glad you did.
Tres.
--
===
Tres Seaver[EMAIL PROTECTED]
Digital Creations "Zope Dealers" http://www.zope.org
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Re: [Zope-dev] ZUnit - feedback convocation
On Thu, Nov 30, 2000 at 11:52:47AM -0800, Michel Pelletier wrote: > > Where would we find this outline? Uh, attached to my original message. []s, |alo + -- Hack and Roll ( http://www.hackandroll.org ) The biggest site for whatever-it-is-that-we-are. http://zope.gf.com.br/lalo mailto:[EMAIL PROTECTED] pgp key: http://zope.gf.com.br/lalo/pessoal/pgp Brazil of Darkness (RPG)--- http://zope.gf.com.br/BroDar ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
Re: [Zope-dev] Return variables from a DTML Method
[EMAIL PROTECTED] writes:
> I want to change some ZClass properties by getting return results
> from a DTML Method. Something like this: "myzclass.propertysheets.get('Basic').manage_changeProperties(dtmlM
> eth(this(),_))">. How do I get the dtmlMeth to return a Mapping?
> (or should I be doing this a different way?)
There will be people that say, you should not do such things
in DTML.
Dieter
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Re: [Zope-dev] ZPatterns: using PythonMethods from Skinscript
At 04:39 PM 11/30/00 +0100, Ulrich Eck wrote:
I've a db_sequence specialist who serves the Framework with
db_id's for new Records like:
May I suggest calling your Specialist "Sequences" or "Counters" since it appears that it returns objects which produce sequential integer values?
>>> newid = db_sequence.getItem('').nextid
The Attribute nextid is provided by a Skinscript-Method:
WITH getNextId(seq_name=self.id)
COMPUTE seq_name=seq_name,nextid=_.int(nextid)
I would not suggest using nextid as an attribute. This should really be a method, e.g. getNextId(). The method should then return the result of calling Counters.getNextId(seq_name=self.id).
However, if you insist on using the above approach, your SkinScript should read:
WITH
getNextId(seq_name=self.id)
COMPUTE
nextid=RESULT['nextid'], seq_name=RESULT['seq_name']
Notice that since your Python method returns a dictionary, RESULT is a dictionary, not an object, so you have to retrieve the elements you want in your expressions that way. Of course, you could just have getNextId() return an integer result, and use:
WITH getNextId(seq_name=self.id) COMPUTE nextid=RESULT
WITH SELF COMPUTE seq_name=id
to achieve the same effects.
My Second "little" Problem:
i'm not the first one who had problems to manage data with rdbms and zpatterns. i can get Attributes through SSMethods
easily and now tried to setup ADD/CHANGE/DELETED Rules to manage data.
Here my SSMethod for this(getEventById/insertEvent/updateEvent are ZSQL-Methods):
WITH QUERY getEventById(id=self.id) COMPUTE sid=_.int(id),name,time_start
WHEN OBJECT ADDED CALL insertEvent(id=self.sid)
WHEN OBJECT ADDED,CHANGED STORE sid,name,time_start
USING updateEvent(id=self.sid,name=self.name,time_start=self.time_start)
I access the Item through loadAttribute: "sid"
I set up a ZClass derived from Dataskin which acts as Storage-Class.
I call
and get back an empty object without any attributes (propertysheet-problem??)
the record in the database is created (but only because I reduced the ZSQL-Insert Method to id-parm only)
this again seems to be a Problem of the namespace I'm in while the _objectAdded() ... method.
Here's what you're missing. There is no "sid" attribute when you add an object. You need to add this to your SkinScript (assuming I'm guessing correctly what sid is supposed to be):
INITIALIZE OBJECT WITH sid=_.int(self.id)
Otherwise, your two ADDED triggers will execute with no value for the sid attribute.
- Do I need a PropertySheet when I only want to access/change/create/delete Items/Attributes from a RDBMS ??
If yes: Which one (CommonInterfaceProp/DataSkinProp)
If no: how do i Access/Change my Properties ??
Yes. DataSkin Property sheets would be the ones you need to use.
- and another Question related to this:
Which object fires the Trigger-Event (ADDED/CHANGED/DELETED) ..
is it the PropertySheet itself ???
When you change the attributes of the object, the action is logged for the trigger to fire at transaction commit time. The Property Sheet is just a way to change the attributes.
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[Zope-dev] Custom Unauthorized errors...
With all the work going on related to Zope's authentication system has there been any progress on allowing custom unauthorized errors? I'd refer to the bug id in the collector, but it seems to be down at the moment. I'm planning on using LoginManager which fixes this to a certain extent last I heard... that is it will let you use a customized unauthorized error when you know who the user is (ie. they've logged in), but not for anonymous users. Just out of curiousity (I'm looking at the source now to figure this out, but I thought it couldn't hurt to ask), why is this? The anonymous user has a user object, and so would seem to be a real user as far as the system goes. I'm tired of hacking custom unauthorized errors into zope all the time, so I'd really like to get this fixed at some point. Any thoughts as to directions to go, or dead ends to be avoided. I'll be looking into this as I find time so any help would be appreciated. -- John Eikenberry [[EMAIL PROTECTED] - http://zhar.net] __ "A society that will trade a little liberty for a little order will deserve neither and lose both." --B. Franklin ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
[Zope-dev] Using LoginManager with SQL and SkinScript
I've put up a writeup of a different way to use LoginManager with SQL that I think is a bit more in keeping with the current ZPatterns at: http://www.zope.org/Members/dlpierson/sqlLogin Any comments? (I would have set this up as a formal HowTo, but couldn't find a way to upload the contents.) Dan Pierson ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
[Zope-dev] ZPatterns: using PythonMethods from Skinscript
hi out there,
this is my first posting on this list. Right now I
think
this is the right place to ask details about
ZPatterns.
I think a ZPatterns-Mailinglist should be set up,
where
people like me, working hard to get the "Zen of
ZPatterns"
can discuss questions related to USING
ZPatterns.
Here my first little problem:
I've a db_sequence specialist who serves the
Framework with
db_id's for new Records like:
>>> newid =
db_sequence.getItem('').nextid
The Attribute nextid is provided by a
Skinscript-Method:
WITH getNextId(seq_name=self.id)
COMPUTE
seq_name=seq_name,nextid=_.int(nextid)
"getNextId()" is a PythonMethod and uses
ZSQL-Methods to
compute the NextId while Locking the Table:
PARAMETER: self, seq_name
self.sql_Lock()nid = 1for cur_id in
self.sql_NextIdGet(seq_name=seq_name): nid = cur_id.nextid +
1 self.sql_NextIdUpdate(seq_name=seq_name,nextid=nid) break
else: self.sql_NextIdCreate(seq_name=seq_name,nextid=1)
self.sql_Unlock()
return {'seq_name':seq_name, 'nextid':nid} # HERE'S
MY PROBLEM I THINK
I tried to return nearly everything expect a certain instance of a
"special getNextId-Return-Object" e.g. return nid / return (seq_name,nid)
...
I tried serveral ways to reach my return values in the SSMethod:
... COMPUTE nextid=nextid or nextid=self.nextid or nextid=RESULT ...
Finally i tried to follow what happens during a get-call of an Attribute in
the source ..
no success ..
except when i use some Dummy ZSQL-Method which does the following and
works (but this is not the way to do it ..)"select as nextid,
as seq_name"
can someone give some advice or enlighten me about the Namespace I'm in, at
SSMethods Attribute providers
at execution-time ?!?
My Second "little" Problem:
i'm not the first one who had problems to manage data with rdbms and
zpatterns. i can get Attributes through SSMethods
easily and now tried to setup ADD/CHANGE/DELETED Rules to manage
data.
Here my SSMethod for
this(getEventById/insertEvent/updateEvent are ZSQL-Methods):
WITH QUERY getEventById(id=self.id) COMPUTE
sid=_.int(id),name,time_start
WHEN OBJECT ADDED CALL insertEvent(id=self.sid)WHEN OBJECT
ADDED,CHANGED STORE sid,name,time_start
USING
updateEvent(id=self.sid,name=self.name,time_start=self.time_start)
I access the Item through loadAttribute:
"sid"
I set up a ZClass derived from Dataskin which acts
as Storage-Class.
I call
and get back an empty object without any attributes
(propertysheet-problem??)
the record in the database is created (but only
because I reduced the ZSQL-Insert Method to id-parm only)
this again seems to be a Problem of the namespace
I'm in while the _objectAdded() ... method.
- Do I need a PropertySheet when I only want to access/change/create/delete Items/Attributes from a RDBMS ??
If yes: Which one
(CommonInterfaceProp/DataSkinProp)
If no: how do i Access/Change my Properties
??
- and another Question related to
this:
Which object fires the Trigger-Event
(ADDED/CHANGED/DELETED) ..
is it the PropertySheet itself
???
lots of questions still there but these are
the points i really tried to get working .. but i did'nt..
hope that there is an answer ..
thanks in advance
Ulrich Eck
net-labs
Re: [Zope-dev] ZUnit - feedback convocation
Lalo Martins wrote: > > Hi all > > I'trying to write a document on ZUnit and Unit Testing in > general, following Michel's and Amos' documentation process. I > wrote an outline, and now I'm stuck :-) anyone with a few free > moments is welcome to take a look and send me some words. Also, > anyone very interested in the subject is welcome to volunteer > for editorial help (read the Process to know what this means). Where would we find this outline? > Thank you. > > (BTW, if you can't understand what an "outline" is, read the > process too. Oh what the heck. If you haven't read it, then > read it, it's very cool reading anyway.) Thanks! -Michel ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
[Zope-dev] Return variables from a DTML Method
I want to change some ZClass properties by getting return results from a DTML Method. Something like this: . How do I get the dtmlMeth to return a Mapping? (or should I be doing this a different way?) Thanks. ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
[Zope-dev] ZUnit - feedback convocation
Hi all I'trying to write a document on ZUnit and Unit Testing in general, following Michel's and Amos' documentation process. I wrote an outline, and now I'm stuck :-) anyone with a few free moments is welcome to take a look and send me some words. Also, anyone very interested in the subject is welcome to volunteer for editorial help (read the Process to know what this means). Thank you. (BTW, if you can't understand what an "outline" is, read the process too. Oh what the heck. If you haven't read it, then read it, it's very cool reading anyway.) []s, |alo + -- Hack and Roll ( http://www.hackandroll.org ) The biggest site for whatever-it-is-that-we-are. http://zope.gf.com.br/lalo mailto:[EMAIL PROTECTED] pgp key: http://zope.gf.com.br/lalo/pessoal/pgp Brazil of Darkness (RPG)--- http://zope.gf.com.br/BroDar Unit testing Zope Products with ZUnit by Lalo Martins Unit Testing What is Unit Testing Where does it come from How should it be done Refactor mercilessly! Writing Tests Importing ZUnit The TestCase class Interfacing with the Zope environment Fixtures The persistence problem - leaving traces behind Grouping tests in TestSuites Wrapping it all up in a creator function Running the tests The TestRunner object TestResults objects Leaving objects behind for debugging
Re: [Zope-dev] OracleStorage, and possibly others
On Thu, Nov 30, 2000 at 08:27:00AM -0500, Jim Fulton wrote: > Lalo Martins wrote: > > > > Anyway, I said "inefficient", not "slow". > > I think you really mean "scalable". No, I meant "inefficient", a purposely vague term ;-) yes, I meant to imply it isn't scalable, but not only that, and as I didn't have the numbers, I prefered to be vague. What you say below for memory usage also falls under "inefficient". Eating into swap can really make a big machine crawl. > OTOH, FileStorage has a huge memory hit for lage databases, because > it keeps an in memory index from oid to file position. It currently > uses a Python dictionary for this. We could probably reduce the memory > hit by about an order of magnitude by switching to a different data > structure, but DCOracleStorage or a Berkeley DB-based storage doesn't > need this index. []s, |alo + -- Hack and Roll ( http://www.hackandroll.org ) The biggest site for whatever-it-is-that-we-are. http://zope.gf.com.br/lalo mailto:[EMAIL PROTECTED] pgp key: http://zope.gf.com.br/lalo/pessoal/pgp Brazil of Darkness (RPG)--- http://zope.gf.com.br/BroDar ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
Re: [Zope-dev] OracleStorage, and possibly others
On Thu, Nov 30, 2000 at 08:10:15AM -0500, Jim Fulton wrote: > Lalo Martins wrote: > > > > Please help stamp out Data.fs! :-) > > I don't think Data.fs will go away. I do expect it to be relagated to > initial evaluation and development projects. Use of Berkely DB in > transactional mode requires a significant andminstration commitment. > Log files need to be purged. Backup and recovery processes need to be in > place. A similar cost is associated with using Oracle and many other databases, > I expect. People aren't going to want to deal with these issues when > initially trying and learning Zope (or ZODB). Sometime it will, I hope. Or at least, be relegated to non-Zope ZODBs where the data volume is very small. But FileStorage will not be replaced by any of the current alternatives, I agree. []s, |alo + -- Hack and Roll ( http://www.hackandroll.org ) The biggest site for whatever-it-is-that-we-are. http://zope.gf.com.br/lalo mailto:[EMAIL PROTECTED] pgp key: http://zope.gf.com.br/lalo/pessoal/pgp Brazil of Darkness (RPG)--- http://zope.gf.com.br/BroDar ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
[Zope-dev] standard_error_message does nothing?
My site uses SiteAccess2, zope 2.2.2, etc. If I got to one of my virtual hosts and enter a bogus URL, I get an error message that includes *another* error message within it (both from HTTPResponse.py's _error_html(). Example: http://docwhat.gerf.org:9673/fish I have modified _error_html() to put a comment at the very start saying where it came from. In addition, the root standard_html_message has a comment at the top and so does the /docwhat stdandard_html_message, both saying which it is. /docwhat is the folder that docwhat.gerf.org's vhost/siteroot is at. The fish url above should generate (I thought) my standard_html_message from /docwhat. I don't understand this at all. It goes against the docs in http://www.zope.org/Members/JohnC/StandardErrorMessage My site includes a view_source that works fairly well, if you want to see the various standard_html_message's. linuxasm.gerf.org is a non-siteaccessed version of my site, with no siteaccess rules. Here are the URLs: docwhat one: http://docwhat.gerf.org:9673/standard_error_message/view_source root one: http://linuxasm.gerf.org:9673/standard_error_message/view_source Thanks for any help. Ciao! -- Those are my principles. If you don't like them I have others. -- Groucho Marx The Doctor What: Second Baseman http://docwhat.gerf.org/ [EMAIL PROTECTED] KF6VNC ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
Re: [Zope-dev] Loginmanager and LDAP
At 07:17 AM 11/28/00 +0100, Magnus Heino (Rivermen) wrote: > > >I'd like to authenticate users using LDAP and Active Directory. Zope is >running on a RH7.0 box. > >Has anyone done this, is it possible? Dunno about Active Directory or RH 7, but Ty and I use LDAP logins with LoginManager all the time on several applications. We've made a custom UserSource for ease of installation on different apps, but we originally developed it using a GenericUserSource and the ZopeLDAP product. You should be able to do the same. ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
Re: [Zope-dev] OracleStorage, and possibly others
"Phillip J. Eby" wrote: > > At 08:10 AM 11/30/00 -0500, Jim Fulton wrote: > > > >I don't think Data.fs will go away. I do expect it to be relagated to > >initial evaluation and development projects. Use of Berkely DB in > > >transactional mode requires a significant andminstration commitment. > >Log files need to be purged. Backup and recovery processes need to be in > >place. > > FWIW, Ty and I talked about using a daemonic thread in BerkeleyStorage to > run periodic checkpoints and purge logfiles. AFAIK, backups of BerkeleyDB > require only that you make a copy of all the associated files. Recovery's > a bit trickier, of course. (We never got around to implementing it because > our tests showed that BerkeleyDB didn't solve the performance issue we were > trying to solve. So we quit working on it at that point.) I don't think the storage should get involved with this. There are alot of knobs and possible policies that can be used. This is all well documented and supported by Sleepycat Software. IMO, when someone uses a Berkeley DB storage they are using Berkeley DB and should learn how to administer it. I don't think it's a good idea to try to hide this from people. Jim -- Jim Fulton mailto:[EMAIL PROTECTED] Python Powered! Technical Director (888) 344-4332http://www.python.org Digital Creationshttp://www.digicool.com http://www.zope.org ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
Re: [Zope-dev] OracleStorage, and possibly others
At 08:10 AM 11/30/00 -0500, Jim Fulton wrote: > >I don't think Data.fs will go away. I do expect it to be relagated to >initial evaluation and development projects. Use of Berkely DB in >transactional mode requires a significant andminstration commitment. >Log files need to be purged. Backup and recovery processes need to be in >place. FWIW, Ty and I talked about using a daemonic thread in BerkeleyStorage to run periodic checkpoints and purge logfiles. AFAIK, backups of BerkeleyDB require only that you make a copy of all the associated files. Recovery's a bit trickier, of course. (We never got around to implementing it because our tests showed that BerkeleyDB didn't solve the performance issue we were trying to solve. So we quit working on it at that point.) ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
[Zope-dev] Re: [Geeks] Re: Interface Meta Data proposal
Guido van Rossum wrote: > > > Is security really a part of an object's interface? I thought this was more > > of an implementation thing. > > Good point. Certainly in Unix I can have two things implementing the > same interface (e.g. two named pipes) with different security > settings (i.e. modes). > > However some security stuff can be part of the interface too: e.g. the > fact that a Foo object has Read, Write and Execute permissions is > usefully specified as part of its interface. Whether a particular Foo > instance has a given permission for a certain user is up to the > instance. I think we're talking about a different level of security setting here. In unix, you have certain fixed permissions (e.g. read, write, execute). The OS maps these permissions onto certain low-level operations for the few objects it knows about. This is about mapping permissions onto objects, rather than deciding what users or groups have what permissions on an object. In Zope, the programmer defines abstract permissions and decides how to map the abstract permissions to object operations. It is this mapping that makes sense for interfaces. Like Unix, Zope has a separate mechanism for deciding what users/roles have what permissions on objects. This should not be part of the object interface. These settings are done by users/administrators. Jim -- Jim Fulton mailto:[EMAIL PROTECTED] Python Powered! Technical Director (888) 344-4332http://www.python.org Digital Creationshttp://www.digicool.com http://www.zope.org ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
Re: [Zope-dev] Re: [Geeks] Interface Meta Data proposal
Chris McDonough wrote: > > Is security really a part of an object's interface? IMO yes. I would go even farther and suggest that different interfaces to an object represent different types of usage and map very nicely to permissions. That is, there might be a one-to-one mapping from interface to permission. In this model, you don't need to make assertions for components of an interface (e.g. attributes and methods, which are just special kinds of attributes), rather you simply say that the whole interface is associated with a particular permission. Jim -- Jim Fulton mailto:[EMAIL PROTECTED] Python Powered! Technical Director (888) 344-4332http://www.python.org Digital Creationshttp://www.digicool.com http://www.zope.org ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
Re: [Zope-dev] OracleStorage, and possibly others
Lalo Martins wrote: > > On Wed, Nov 29, 2000 at 07:02:50AM -0500, Chris McDonough wrote: > > > Of course it would, for the same reasons as OracleStorage (eg > > > FileStorage/Data.fs is inefficient) > > > > Actually, it's the other way around. OracleStorage is 30-to-50 times slower > > than FileStorage on writes. Reads are slow too but the slowness is somewhat > > negated by caching. > > Chris, that's only true for small databases. At about 100M of > Data.fs, OracleStorage starts being faster. It depends on > hardware too. We made some benchmarks on a major Brazilian > portal, and well, it's currently running OracleStorage. > > Anyway, I said "inefficient", not "slow". I think you really mean "scalable". I suspect that FileStorage will be faster and use less disk that OracleStorage, or any other storage, at least when supporting undo. To get even comparible speed from Oracle requires substantial optimization on the Oracle side. Our customer was able to substantially improve DCOracleStorage performance by doing things like putting tables and indexes on different disk *controllers*. :) OTOH, FileStorage has a huge memory hit for lage databases, because it keeps an in memory index from oid to file position. It currently uses a Python dictionary for this. We could probably reduce the memory hit by about an order of magnitude by switching to a different data structure, but DCOracleStorage or a Berkeley DB-based storage doesn't need this index. Initial tests with my latest Berkeley DB-based storage show it to be about three times slower than FileStorage. I suspect that if the logs and data files were put on separate disks, as Sleepycat Software recommends, that the speed difference could be reduced quite a bit. Note that, until recently, FileStorage couldn't be used with databases over 2GB in size, due to a bug that was fixed at around the same time that we released the DCOracleStorage. We have a customer who has a 10GB FileStorage. You need large-file support in Python for your OS to be able to go over 2GB. Jim -- Jim Fulton mailto:[EMAIL PROTECTED] Python Powered! Technical Director (888) 344-4332http://www.python.org Digital Creationshttp://www.digicool.com http://www.zope.org ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
Re: [Zope-dev] OracleStorage, and possibly others
Lalo Martins wrote: > > Well, two betas of OracleStorage in one day, then a month and a > half of silence. What's the status? >From our perspective, it's what it was then. We built it for a customer who later decided they didn't want it. I'm glad to hear you found it useful. > What about the other Storage projects? BerkeleyStorage has been > dead for an year, and I heard pretty nasty words about > InterbaseStorage. What about someone who wanted to try to port > OracleStorage to Postgres or some other RDBMS? We're working on a new suite of Berkeley storages that we are writing to the the latest Berkeley database APIs. As Chris pointed out, these are based on a new Berkeley DB extension that Andrew Kuchling started and that Robin Dunn is finishing. There are a number of interesting new features that will eventually result from these storages: - A new pack/garbage collection approach. The current storages perform a mark-and-sweep garbage collection when packing. It turns out that this really isn't very scalable. I'm going two switch to using the same garbage-collection strategy that Python uses, which is reference counting supplimented by an incremental cyclic garbage detection algorithm. I have a simple storage (no undo or versions) that needs no packing of your data structures are free of cycles. I'm hopeful that we can make packing automatic and incremental. - Undo-log generation will be much faster, at least for common cases. Generation of undo logs (for selecting transactions to undo) is becoming a significant performance problem with FileStorage. - ZEO verification, performed when a client with a persistent cache starts up, will be much faster. - Policies to control whether multiple revisions are stored or whether revisions are removed by packing on a object-by-object or transaction-by-transaction basis. For example, you could have a poll/votting product that didn't allow undo of and didn't require storing multiple records for votes. This would be cleaner than mounting a separate database with a simple storage. You could keep significant historical revisions for important objects, such as Wiki pages, templates, scripts, etc., with a policy to decide which revisions are significant. - The ability to set policies to implement quotas. I expect that we'll work out a lot of these ideas for Berkeley storages and then implement them in OrcaleStorage. Others should then be able to map the implementation onto other storages. I'll note, in passing, that it's much nicer working these ideas out with the BerkelyDB API than dealing with PLSQL or Python SQL. We are also working on ZEO storage replication. This may have a big impact on the storage API, or lead to specialized APIs for replicated storages. > Please help stamp out Data.fs! :-) I don't think Data.fs will go away. I do expect it to be relagated to initial evaluation and development projects. Use of Berkely DB in transactional mode requires a significant andminstration commitment. Log files need to be purged. Backup and recovery processes need to be in place. A similar cost is associated with using Oracle and many other databases, I expect. People aren't going to want to deal with these issues when initially trying and learning Zope (or ZODB). Jim -- Jim Fulton mailto:[EMAIL PROTECTED] Python Powered! Technical Director (888) 344-4332http://www.python.org Digital Creationshttp://www.digicool.com http://www.zope.org ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
Re: [Zope-dev] Interfaces: Specify, then implement!
Dieter Maurer wrote: > > If you do change the implementation, then the specification > can probably be changed at the same time. IMHO, this is the wrong way round. If the interface doesn't cover what it needs to, update the interface and then make sure all the implementations are updated afterwards. cheers, Chris ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
Re: [Zope-dev] time stamp - concurrent editing
"Nai A. Tzeo" wrote: > > Hello, > > I'm a zope newbie and was wondering if anyone on the list know how to solve > the problem of concurrent editing. I'm using zope as a front end and SQL > server as a back end. Basically, I want to be able to edit a record with > out having to lock the record so that others can use it but I want to make > sure that when I update and save my changes that I don't overwrite someone > elses changes. I was thinking about time stamping the record every time a > person grabs the records in update view. Before the changes are written to > the database, the timestamps on both the record that's checked out and the > record that was modified should be compare. If the timestamp in the > database is more recent, meaning someone has updated the record, then I > can't update the record with my changes. I would need to grab the latest > copy from the database and add in my changes. I know this sounds really > inefficient but I can't think of another way. If anyone have other ideas or > thoughts, pass it along. It will be greatly appreciated. thoughts, doing programmtic merging of changes is going to be scary (perhaps exploring the diffs command that cvs uses (rdiff?), however you do it, you should probably do some auditing tables to make sure changes are never discarded completely (depending on app and load). scenario (extermely record dependent). assuming shared document stored in the db for this example. joe smoe goes to edit screen. leaves for two week vacation jane doe goes to edit screen. types in her magnum opus. joe comes back, types 'vacation ruled' and saves. jane looks back at screen, screams, and takes two year vacation. purely, adding in changes can't always assume nesc that a doc is always getting bigger (again this extremely app specific). regardless, IMO for this type app domain mysql isn't a good db for this type of app (no transaction support, no stored procs/triggers) ideas, switch to a db with real mvcc where you don't have to block your readers on writers to achieve isolation (something like... postgres). add some triggers to create audit. use sequences instead of timestamps for revision ids(store timestamps for human views, but programatically using the db for ts manipulation and indexing is very db specific and limited by that db ts internals, sequences achieve the same result, are faster, and are ansi-sql compliant). if you do decide to do locks, allow temp locks based on ts, check edit requests on ts of lock and approve/deny/create new, etc. kapil ___ Zope-Dev maillist - [EMAIL PROTECTED] 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 )
