Re: [Openslp-devel] SLPReg fresh=false

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Hi John,

We started code change based on the latest OpenSLP 2.x source downloaded from the URL https://openslp.svn.sourceforge.net/svnroot/openslp/trunk.

In order to merge the changes into  the stable OpenSLP release code, can you provide the stable source code which used to build the OpenSLP 2.0.0 Beta 2 installer?

Or, should we send the code to you to merge into the system?

Ren

-----Original Message-----
From: John Calcote [mailto:joh...@gm...] 
Sent: Friday, January 11, 2013 11:29 AM
To: Wang, Ren
Cc: 'OpenSLP Devel Mailing List'
Subject: RE: SLPReg fresh=false

Just write clean code and try to conform the style that appears in the existing code base - for consistency. Nothing written down.

--John

> -----Original Message-----
> From: Wang, Ren [mailto:Ren...@nu...]
> Sent: Friday, January 11, 2013 5:28 AM
> To: John Calcote
> Cc: 'OpenSLP Devel Mailing List'
> Subject: RE: SLPReg fresh=false
> 
> John,
> 
> Is there any development guideline or design that we need to 
> understand and follow for the implementation?
> 
> Ren
> 
> -----Original Message-----
> From: John Calcote [mailto:joh...@gm...]
> Sent: Wednesday, January 09, 2013 1:40 PM
> To: Wang, Ren
> Cc: 'OpenSLP Devel Mailing List'
> Subject: RE: SLPReg fresh=false
> 
> If you are going to implement it anyway, please feel free to 
> contribute
the
> patch. We'll evaluate it as a community to understand the impact. If 
> it
doesn't
> impact performance much, we'll probably take it. I agree that slpv2bis 
> is
not
> slpv2, however, we've planned to do other bis features, such as mesh- 
> enhanced slp in v2 at some point. But please do submit the patch - I'm
open
> to new features, as long as the issues and concerns are managed properly.
> 
> John
> 
> > -----Original Message-----
> > From: Wang, Ren [mailto:Ren...@nu...]
> > Sent: Wednesday, January 09, 2013 11:13 AM
> > To: John Calcote
> > Cc: OpenSLP Devel Mailing List
> > Subject: RE: SLPReg fresh=false
> >
> > Hi John,
> >
> > I can understand the reason for not supporting it. But, jSLP and Sun
> support
> > it.
> >
> > I can't find a formal RFC to drop the feature as well. Do you mind 
> > if we
> as a
> > contributor for this feature?
> >
> > Ren
> >
> > -----Original Message-----
> > From: John Calcote [mailto:joh...@gm...]
> > Sent: Tuesday, January 08, 2013 1:26 PM
> > To: Wang, Ren
> > Cc: OpenSLP Devel Mailing List
> > Subject: RE: SLPReg fresh=false
> >
> > Hi Ren,
> >
> > After a scan of the mailing list archives for the srvloc project on
> sf.net, I found
> > the following message submitted by Matt Peterson:
> >
> > http://sourceforge.net/mailarchive/message.php?msg_id=3209418
> >
> > This message explains the rationale behind disabling incremental 
> > service registration and deregistration. I agree with Matt's 
> > assessment and feel
> that
> > we should keep the code as is - incremental service registration is 
> > not supported in OpenSLP because using it overtaxes the SLP protocol.
> > If you need incremental registration and deregistration, perhaps you 
> > should consider using LDAP instead of SLP.
> >
> > Any comments are appreciated (from anyone).
> >
> > John
> >
> > > -----Original Message-----
> > > From: John Calcote [mailto:joh...@gm...]
> > > Sent: Tuesday, January 08, 2013 11:09 AM
> > > To: 'Wang, Ren'
> > > Cc: OpenSLP Devel Mailing List 
> > > (ope...@li...)
> > > Subject: RE: SLPReg fresh=false
> > >
> > > (Adding devel list back in so others can chime in if they have
> > > input)
> > >
> > > Hi Ren,
> > >
> > > Ok - I was correct in my understanding then - I thought I 
> > > understood that
> > you
> > > wanted incremental registrations. My original reply to you was 
> > > that the entire concept of incremental registrations appears to be 
> > > deprecated in slpv2bis, which is the standard that OpenSLP is 
> > > trying to
> > follow.
> > >
> > > Incremental registrations is controlled by the FRESH flag in SLP 
> > > message headers, and the FRESH flag is required to be set to 1 by 
> > > slpv2bis. What I
> > > *don't* know is why. I don't see any explanation anywhere of why 
> > > this flag was deprecated and required to be set to 1 in message 
> > > headers. I presume that Matt Peterson disabled the use of the 
> > > boolean fresh field in the
> > SLPReg
> > > api in order to support the deprecation of incremental registrations.
> > >
> > > In this document: http://srvloc.sourceforge.net/compatibility.html
> > > the
> > fresh
> > > flag is listed under the SLPv2 column as:
> > >
> > > "When this flag is present in a SrvReg, this registration 
> > > overwrites any existing registration with the same URL. When this 
> > > flag is absent, a
> > SrvReg will
> > > incrementally add to an existing registration."
> > >
> > > And under the slpv2bis column as:
> > >
> > > "As RFC 2608, except that the Fresh Flag MUST be set on registrations.
> > > If
> > not,
> > > return a FRESH_MUST_BE_SET error?" (The error code to be returned 
> > > was properly defined after this document was created.)
> > >
> > > In other words, since the current implementation of OpenSLP tries 
> > > to support SLPv2bis as closely as possible, we've disabled 
> > > incremental registration by ignoring the Boolean fresh argument 
> > > passed to SLPReg and hard-coding the FRESH flag in the SrvReg message header to 1.
> > > Note that
> > this
> > > flag is not a tri-state - the field is always present, and must be 
> > > either
> > 1 or 0. At
> > > certain places in the documents referenced on this thread, it 
> > > appears that the flag may be present or not, and if present it 
> > > must be 1 and may not be zero. The flags word is always present, 
> > > and the FRESH flag is hard-coded
> > to a
> > > particular position in this word, so it must be present, and must 
> > > be set
> > to 1.
> > > Since setting this flag to 1 means the registration is fresh, the
> > registration will
> > > overwrite any existing registration.
> > >
> > > Once again, I don't know why this was done - no documents I've 
> > > been able
> > to
> > > find on the topic seem to indicate the rationale or discussion of 
> > > the
> > issue that
> > > caused the change. If anyone on the list knows, please chime in.
> > >
> > > Please understand Ren, that I'm not against incremental refresh - 
> > > if I understood the rationale begin removing it, I would be able 
> > > to make an intelligent decision about whether to follow the 
> > > standard in
this
> area.
> > Since I
> > > don't know why it was deprecated, I have only the wording of the 
> > > standard to go by. If you can find any documentation on the net as 
> > > to why it was removed in the first place, I'd appreciate your insight.
> > >
> > > John
> > >
> > > > -----Original Message-----
> > > > From: Wang, Ren [mailto:Ren...@nu...]
> > > > Sent: Tuesday, January 08, 2013 9:21 AM
> > > > To: John Calcote
> > > > Subject: RE: SLPReg fresh=false
> > > >
> > > > Hi John,
> > > >
> > > > What we are looking for is to support incremental service
> registrations.
> > > >
> > > > For example, if there is a service registered with attribute 
> > > > (user_id= Ren), and later a new user added to the service, so 
> > > > the increment registration will call SLPReg with attr 
> > > > (user_id=John) and fresh flag set to false to indicate it is an 
> > > > incremental registration. In the registry, the service should 
> > > > have attribute
> > (user_id=Ren, John).
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > -----Original Message-----
> > > > From: John Calcote [mailto:joh...@gm...]
> > > > Sent: Tuesday, January 08, 2013 11:13 AM
> > > > To: Wang, Ren
> > > > Subject: RE: SLPReg fresh=false
> > > >
> > > > I'm sorry Ren, I still don't understand what you're after. 
> > > > Please forgive my incomprehension - if you could explain exactly 
> > > > what you want to use the fresh flag for and why, then perhaps 
> > > > I'd understand what you're asking. I was simply explaining why 
> > > > it's currently
> > implemented
> > > (or not) the way it is.
> > > >
> > > > John
> > > >
> > > > > -----Original Message-----
> > > > > From: Wang, Ren [mailto:Ren...@nu...]
> > > > > Sent: Tuesday, January 08, 2013 8:07 AM
> > > > > To: joh...@gm...
> > > > > Subject: RE: SLPReg fresh=false
> > > > >
> > > > > Hi John,
> > > > >
> > > > > Thank you again for your response and the URLs.
> > > > >
> > > > > Maybe my question was not clear to you, but I was trying to 
> > > > > ask if OpenSLP will support fresh=false instead of not set the 
> > > > > fresh
flag.
> > > > > On you second
> > > > URL,
> > > > > page 6, it says  "FRESH" MUST be set to 1 on every SrvReg.
> > > > > Otherwise,
> > > > MUST
> > > > > be 0."
> > > > >
> > > > > Since current OpenSLP implementation does not support 0 for
> SrvReg.
> > > > > Based on the OpenSLP.org, "Currently, OpenSLP does not support 
> > > > > incremental registrations.  If fresh is SLP_FALSE, SLPReg() 
> > > > > will return SLP_NOT_IMPLEMENTED."
> > > > >
> > > > > This is why I want to know if you plan to support it.
> > > > >
> > > > > Regards,
> > > > >
> > > > > Ren
> > > > >
> > > > > -----Original Message-----
> > > > > From: John Calcote [mailto:joh...@gm...]
> > > > > Sent: Monday, January 07, 2013 6:37 PM
> > > > > To: Wang, Ren
> > > > > Cc: ope...@li...
> > > > > Subject: RE: SLPReg fresh=false
> > > > >
> > > > > Hi Ren,
> > > > >
> > > > > The FRESH flag was deprecated after RFC 2608 was published.
> > > > >
> > > > > See:
> > > > >
> > > > > http://srvloc.sourceforge.net/new_drafts/draft-guttman-svrloc-
> > > > > as-
> 00.
> > > > > tx
> > > > > t
> > > > > http://srvloc.sourceforge.net/new_drafts/draft-guttman-svrloc-
> > > > > rf
> > > > > c2
> > > > > 60
> > > > > 8b
> > > > > is-
> > > > > 01.
> > > > > txt
> > > > >
> > > > > In the first document it states on page 3 that an error
> > > > > (INVALID_UPDATE)
> > > > is
> > > > > returned by the SA/DA for registrations that don't set the 
> > > > > FRESH flag in
> > > > post
> > > > > slpv2 implementations (slpv2bis - the second document - pp 6, 
> > > > > 7,
> 21).
> > > > > The slpv2bis document isn't clear as to why the FRESH flag 
> > > > > must be set
> > > > > -
> > > > just
> > > > > states that it must be set. I presume it's a security issue of 
> > > > > some
> > kind.
> > > > >
> > > > > John
> > > > >
> > > > > > -----Original Message-----
> > > > > > From: Wang, Ren [mailto:Ren...@nu...]
> > > > > > Sent: Monday, January 07, 2013 9:08 AM
> > > > > > To: John Calcote
> > > > > > Cc: ope...@li...
> > > > > > Subject: SLPReg fresh=false
> > > > > >
> > > > > > Hi John,
> > > > > >
> > > > > > Is there a plan to support fresh=false for SLPReg API?
> > > > > >
> > > > > > Since it is a required feature for our project, we may need 
> > > > > > to provide the change to the OpenSLP if there is no short 
> > > > > > term plan to
> > > > support it.
> > > > > >
> > > > > > Regards,
> > > > > >
> > > > > > Ren
> > > >
> >
> 