January 2003 - Zope - Zope lists

XML-RPC,Zope and Vb.NET Client Application
by Zope＠Stylus 30 Jan '03

30 Jan '03

HI Thanks for this very detailed explanation. I would like to explain what I have understood with respect to XML-RPC I have a client side application in VB.NET sending XML-RPC request on a TCP connection The Linux Machine on which Zope-2.5.1 is installed and running on port 8080 also has an XML-RPC server running on port 9092 on the machine (xmlrpclib from www.pythonware.com ) But I have understood that Zope understands XML-RPC requests without a Server running on the machine. That means even if I dont have an XML-RPC server running on the Linux machine it is ok as long as the request is to the Zope Server. SInce I am sending requests to Python Scripts written in Zope and the Zope server understands XML-RPC requests I dont need a separate XML-RPC Server for this. But if I was trying to access any other python files outside Zope then I would need to have an XML_RPC server running tp listen to the requests. Also since my requests to Zope are coming over the TCP it is keeping a track of the server and Client details. So the Server knows from which IP the request has come. The Problem arises because the Proxy Server I.P. from my firm is the I.P that the server will get with a request. But within the LAN there are a number of machines sending requests to the Remote Zope Server simultaneously. When the Zope Server sends response it will send the reponses back to the coprrect I.P. which is the Proxy I.P. But then requests from each machine in the LAN will need to be tracked by the Proxy with respect to say some unique Identifying Variable that I send with each request and response. I don't know how clearly I have been able to explain what I am trying to do here. I have been able to send and receive request and responses based on a unique Id generated when the User Logs in to the Application. This Id is generated in Zope and sent back along with the response after validating the USer for correct Login. Now everytime a Request or response is sent till the time that the User doesnot Log out the Same process of sending and Receiving requests and responses along with the Unoique Id is how I am doing it. Could anyone think of a better Idea as to how to solve this problem in a more defined Manner? All help received is GREATLY appreciated. Thanks and Best regards John Kunchandy ============================================================================ ======= jwsacksteder(a)ramprecision.com <jwsacksteder(a)ramprecision.com> Think about it like this: > > XML-RPC works exactly like web page requests. Normally a browser contacts a > web server with a tcp connection and sends a http GET command. The server > then responds with a HTML document ON THE SAME TCP CONNECTION. > > With XML-RPC you are sending a RPC request as a formatted XML document to a > server over the HTTP transport protocol and the server responds by sending > the results of that RPC request back as formatted XML. > > In this situation, you are bound by the limitations of that single tcp > connection. Most notably, idle timeouts. If you have a request that takes 15 > minutes to process, the tcp connection will have died long before the > request comes back. XML-RPC does not specifically address persistant > connections like this. SOAP is an extension of XML-RPC that adds support for > this, though some would say that goes against the principles of XML-RPC. > > Most likely, what you want is to have XML-RPC servers/listeners on the > clients as well. What you have then is a peer-to-peer messaging network. A > client can send a XML-RPC request to a server, along with its address, name > and cryptographic key and when the response is ready, the server will > initate a NEW XML-RPC message and send it back to the originator. If you use > a public-key crypto system, you are protected from sending data to the wrong > client if the ip address changes. > > If you had a application where a server needed to notify clients when > certain things happened, you would have to make the clients register > themselves somehow with the server when they first started. Otherwise the > server would never know where the clients are. > > It might be worth your time to run through the XML-RPC transaction by hand > to see what is happening. Just telnet to whatever port your server is > listening(ex. telnet 192.168.0.1 80) on and type a simple XML-PRC request > and see what comes back in the terminal window. ============================================================================ ======== > I am working on an VB.NET client side application that sends requests in > XML-RPC to a Zope server running on Linux(Mandrake 8.0) > The request calls a python script and it returns a String . > But when there are multiple requests (i.e; from different machines on the > network) .the XmlRPc Server throws an XML RPC Fault Error. The 2.6 "xmlrpc.py" file provides support for a traceback. It will tell you about the location and cause of the exception. I think, I posted a patch with similar functionality for Zope 2.5.1. Search the archives... > Does XML-RPC Server maintain a record of the IP address of the client > machine that sent the request so that it can respond back to the same > machine? No, it does not. TCP/IP connections (and therefore HTTP and XML-RPC connections) are bi-directional. You can read and write to them. TCP/IP transparently handles the transport. (Of course, TCP/IP knows the IP address of both ends of the connection). Dieter > --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com) Version: 6.0.443 / Virus Database: 248 - Release Date: 1/10/2003

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RE: [Zope] Hardware for Zope + ZEO
by sean.upton＠uniontrib.com 30 Jan '03

30 Jan '03

On the subject of inodes, file-handles, etc. Would it not also be wise on a heavily loaded storage to allow for a large number of file descriptors to be available to the ZSS process? I think 1024 is the default under Linux for normal users, would it not be wise just in case to run 'ulimit -HSn 8192' to bump up the total number of file descriptors available to the ZSS and DirectoryStorage? One other thing that looks interesting, if there are a lot of writes, is flash+dram combo solid-state storage devices, like those from BitMicro, to use as an options for a DirectoryStorage journal directory. I've never used something like this, so I'm just speculating, but it could be possible to decrease the likelihood of conflict errors if you are able to give quick initial writes (that are buffered within the device dram before sync to flash); this might safely yield better performance without needing to turn off fsync. Sean -----Original Message----- From: Mario Valente [mailto:mvalente@ruido-visual.pt] Sent: Wednesday, January 29, 2003 9:33 AM To: Toby Dickenson; Wankyu Choi; zope(a)zope.org Subject: Re: [Zope] Hardware for Zope + ZEO At 14:17 29-01-2003 +0000, Toby Dickenson wrote: >On Wednesday 29 January 2003 1:37 pm, Mario Valente wrote: > >> OK. Make sure that the clients are connected to the backend >> server (the one above) on a private network. > >For security or performance reasons? > Both, of course. >> fast. We've been looking at DirectoryStorage but right now its still not >> final > >FYI, we hit 1.0.0 a few weeks ago. > Yes, I'm aware of that. Nonetheless we prefer to "road test" it for a while on less important less traficked sites before we go whole hog :-) >> and we're afraid that at some point (ie large sites with lots of >> objects) the OS might run out of file handles. > >Apart from two lock files, DirectoryStorage only opens file handles >momentarily. > >On some filesystems you may want to be concerned with running out of inodes. >On linux I strongly recommend reiserfs, which does not have this problem >because it can create inodes on demand. > I was actually thinking inodes when I wrote filehandles. Thanks for the aditional info on reiserfs. >> All images should be stored as External >> Files (as well as any other BLOBs like PDF files, DOC files, etc). > >Im not sure that advice is universally true, unless your blobs are never >change or mastered elsewhere. Putting everything in ZODB/ZEO simplifies >backups, replication, and distribution of changes. > If you put all images/docs/whatever in a single directory or directory tree you have simpler solutions to backup, replication and distribution. We found out by experience that its not beneficial to store large binary files in Zope, especially when there are constant file uploads going on. C U! -- Mario Valente _______________________________________________ Zope maillist - Zope(a)zope.org http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )

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ZCatalog and Xron
by Luton, Alex 30 Jan '03

30 Jan '03

I'm in the process of trying to build a reliable, accurate search engine using a ZCatalog. In order to keep the catalog contents up to date, I added an Xron method to reindex the catalog every hour. This worked fine on a small site, but for a site with a catalog of 1300 documents the data.fs file grows from a few hundred meg to several gig before long, and apache/zope dies. Another problem is that Xron seems to trigger its methods as many times as it 'missed' if the server is stopped for a while. I'm only indexing dtml documents, and the ZCatalog doesn't use any metadata or special indexes. Are there any ways to prevent the catalog updates being stored in the ZODB, so no undo history is saved for the ZCatalog? Thanks -- Alex This e-mail and any attached files are confidential and are intended solely for the use of the individual or entity to whom they are addressed. This communication represents the originators personal views and opinions, which do not necessarily reflect those of The Royal College of Surgeons of England. If you are not the intended recipient, or the person responsible for delivering the e-mail to the intended recipient, be advised that you have received this e-mail in error, and that any use, dissemination, forwarding, printing or copying of this e-mail is strictly prohibited. http://www.rcseng.ac.uk Registered Charity Number: 212808

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Re: [Zope] "The strange DateTime"
by Rares Vernica 30 Jan '03

30 Jan '03

Yes, that's not a valid DateTime. The funny thing is that I don't get any error message. ;-) Regards, Rares >From: Andreas Jung <lists(a)andreas-jung.com> >Reply-To: Andreas Jung <lists(a)andreas-jung.com> >To: Rares Vernica <verni0(a)hotmail.com>, zope(a)zope.org >Subject: Re: [Zope] "The strange DateTime" >Date: Wed, 29 Jan 2003 12:46:00 +0100 > >DateTime tries to be smart but it is not always all the time. >On the other hand 23/23/23 is not a valid date. > >-aj > >--On Mittwoch, 29. Januar 2003 12:45 +0200 Rares Vernica ><verni0(a)hotmail.com> wrote: > >>Hi, >> >>I have a real nice one here. >> >>>>>import DateTime >>>>>a=DateTime.DateTime("23/23/23") >>>>>a >>DateTime('2003/01/29') >> >>Today is 29-01-2003. >>Can you help me, maybe I'm wrong?! >> >>Thanks in advance, >>Rares >> >> >>_________________________________________________________________ >>MSN 8 helps eliminate e-mail viruses. Get 2 months FREE*. >>http://join.msn.com/?page=features/virus >> >> >>_______________________________________________ >>Zope maillist - Zope(a)zope.org >>http://lists.zope.org/mailman/listinfo/zope >>** No cross posts or HTML encoding! ** >>(Related lists - http://lists.zope.org/mailman/listinfo/zope-announce >> http://lists.zope.org/mailman/listinfo/zope-dev ) > > > > > --------------------------------------------------------------------- > - Andreas Jung http://www.andreas-jung.com - > - EMail: andreas at andreas-jung.com - > - "Life is too short to (re)write parsers" - > --------------------------------------------------------------------- _________________________________________________________________ Add photos to your messages with MSN 8. Get 2 months FREE*. http://join.msn.com/?page=features/featuredemail

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RE: Silva-Error on edit-, metadata or access-tab - solved!!
by Elena Schulz 30 Jan '03

30 Jan '03

Hi, the problem is the Silva-0.8.zexp example. It seems not to be compatible with Silva-0.8.6.1 at least under my conditions (zope 2.6 on win98). Creating a new instance of Silva works fine. -- Elena

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Re: [Zope] ZODB file size
by J C Lawrence 30 Jan '03

30 Jan '03

On Thu, 30 Jan 2003 08:14:40 +0100 Andreas Jung <lists(a)andreas-jung.com> wrote: > --On Mittwoch, 29. Januar 2003 23:07 -0800 J C Lawrence > <claw(a)kanga.nu> wrote: >> What, if any, are the methods of growing a ZODB data store under Zope >> larger than 2Gig? > Install Python with largefile support. And maybe check the mailing > list archive since this question has been asked and answered several > times. Ahh, thanks, I forgot that the ZO search didn't hit the archives as well. Sorry for the FAQ. -- J C Lawrence ---------(*) Satan, oscillate my metallic sonatas. claw(a)kanga.nu He lived as a devil, eh? http://www.kanga.nu/~claw/ Evil is a name of a foeman, as I live.

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ZODB file size
by J C Lawrence 30 Jan '03

30 Jan '03

What, if any, are the methods of growing a ZODB data store under Zope larger than 2Gig? I'm loosely expecting on the order of 15Gig of data which will need to be directly managed by a Zope instance and have the obvious scalability question. Sadly nothing has sprung up on my googling or wandering of Zope.org. -- J C Lawrence ---------(*) Satan, oscillate my metallic sonatas. claw(a)kanga.nu He lived as a devil, eh? http://www.kanga.nu/~claw/ Evil is a name of a foeman, as I live.

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Displaying BLOB's with Zope
by Mark Evans 30 Jan '03

30 Jan '03

Hi all, I have been reading everything I can find on the web on this and just can't find exactly what I need. I hope someone can help. I have recently begun learning about BLOBs in Oracle8i. I have successfully created a table 'blobtest' consisting of two fields, 'ID' and 'Image' and loaded a jpeg file into it using sqlloader. I am using DCOracle2, Zope2.5.1,Mozilla1.x and Python2.2.1. Zope and Oracle are running on Solaris and my client is W2K. I have an external method called 'blobtest' that retrieves the blob: import string, DCOracle2 as dco def main (): dCon = dco.connect("foo/moo@myfoo") dCur = dCon.cursor() sql = "select image from blobtest where id='1'" dCur.execute(sql) result = dCur.fetchone() lob = result[0] pic = lob.read() return pic I have a DTML method that calls the External Method: <dtml-var standard_html_header> Method 1: Display image in-line, retrieved by External Method<BR> <img src=&dtml-blobtest;> </p> <dtml-var standard_html_footer> What I want it to do is display the image on the html page. What it does is open a browser dialog box asking me to select an application to open a file of type 'application/octet-stream'. If I select an image viewing program like IrfanView, Irfan tells me the file is of type jpeg, but missing the file extension. When I click 'ok' it displays the correct image and displays it properly. This leads me to suspect that a) the blob that is returned does not have a name and therefore doesn't have a file type extension and b) my problem probably has something to do with setting the content-type header properly to image/jpeg. How do I do this using an external method? Alternatively, I have tried to adapt the MySQL HowTo by murphy ( http://www.zope.org/Members/murphy/MySQL-BLOBs) in the following way: Created a python script called 'retrieveImage': photo = context.getImage() container.REQUEST.RESPONSE.setHeader('content-type', 'image/jpeg') return photo[0].image which calls the ZSQL method 'getImage': select image from blobtest where id='1' When I click on the 'test' tab for the python script, I get the following message: The image "http://foo.com/blobtest2/retrieveImage" cannot be displayed, because it contains errors. What am I missing here? Thanks in advance for the help. Regards, Mark Evans

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Is DTML needed for Python Products?
by Jon Whitener 30 Jan '03

30 Jan '03

I will soon try to create my first Python Product on the file system for Zope. Is it necessary or better to use DTML for the product's Web interfaces, or can I try to use Page Templates instead? All of the documentation tends to discuss DTML methods. Is using ZPT much different or more difficult? Thanks in advance, Jon Jon Whitener Detroit Michigan USA

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Two more questions...
by Thierry Florac 29 Jan '03

29 Jan '03

Hi, two more questions about Zope : 1. I think that I've made several mistakes while assigning Zope permissions. Is there any way to reinitialize Zope permissions on all objects with their default value ? 2. I'm using ZSession product to store sessions instances of Zope persistent objects. When calling "absolute_url()" on these objects, the SiteRoot object located in my Zope site is not taken into account. Is it a normal behaviour ?? Thanks for any answer... Thierry -- Linux every day, keeps Dr Watson away... http://gpc.sourceforge.net -- http://www.ulthar.net

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