Re: [apps-discuss] Aggregated service discovery

[William Mills <[e-mail]>]

Paul, 


Thanks for the reply on this.  I do already have a separate doc for registering the OAuth specific relations, http://tools.ietf.org/id/draft-wmills-oauth-lrdd-01.html


I don't think I like the thought of having to register a new link type for every service, but that might be the right way.  IMAP already has a URI defined for example so if we use a more general link relation then the URI scheme details the type.  The tradeoff is whether you can look for a specific link-type or if you have to scan list elements for the URI type you need.

-bill





>________________________________
> From: Paul E. Jones <[e-mail]>
>To: 'William Mills' <[e-mail]>; 'Peter Saint-Andre' <[e-mail]> 
>Cc: 'Cyrus Daboo' <[e-mail]>; [e-mail] 
>Sent: Sunday, June 17, 2012 6:48 PM
>Subject: RE: [apps-discuss] Aggregated service discovery
> 
>
>Bill,
> 
>My apologies for the belated reply.  I’ve been busy this week and got rather behind on email.
> 
>I do not personally like using SRV records, either.  SRV records could work for smaller domains, but I’m not sure that they’re the best solution for larger domains.  Personally, I would prefer putting users on specific servers or server clusters and SRV records will not differentiate users. 
> 
>To use WebFinger to find one’s IMAP, SMTP, or POP server, we could do as I suggested in my email.  Now the question is what does one query?  Since these three services are email, I’d suggest we query “mailto:[e-mail]”.  We could use another URI scheme (e.g., “acct:”), but mailto seems most appropriate given that you’re seeking info about mail services.
> 
>I provided an example earlier that would simply point to a config file with server information.  We could do this directly via WebFinger like this:
> 
>GET /.well-known/host-meta?resource=mailto:[e-mail]
> 
>This query would then return something like this:
> 
>{
>  "subject" : "mailto:[e-mail]",
>  "links" :
>  [
>    {
>      "rel" : "smtp-server",
>      "properties" :
>      {
>        "host" : "smtp.packetizer.com",
>        "port" : "587",
>        "login-required" : "yes",
>        "transport" : "starttls"
>      }
>    },
>    {
>      "rel" : "imap-server",
>      "properties" :
>      {
>        "host" : "imap.packetizer.com",
>        "port" : "993",
>        "transport" : "ssl"
>      }
>    }
>  ]
>}
> 
>We would need to standardize the link relation values (smtp-server and imap-server).  We would also need to document what the various properties would be.  If you would like to create such a configuration document based on WebFinger, I’d be happy to help out.  In any case, you can see that WebFinger would serve quite nicely for conveying configuration information given a user’s email ID.
> 
>I’m not sure exactly what you would need for OAuth endpoints, but I would suggest you make that a separate document since it is not mail related.  (At least I assume it’s not.  Even if it were, the mail server information and OAuth information are still different animals.)
> 
>Paul
> 
>From:William Mills [mailto:[e-mail]] 
>Sent: Wednesday, June 13, 2012 7:32 PM
>To: Peter Saint-Andre
>Cc: Paul E. Jones; 'Cyrus Daboo'; [e-mail]
>Subject: Re: [apps-discuss] Aggregated service discovery
> 
>In my use case it's a service/server.
> 
>Not a terribly happy answer to say "DNS SRV records won't work for you, and there is no other solution.".  By the same token I could ask "Why do we need Webfinger and host meta at all if we have DNS SRV records?".
> 
>If XMPP uses SRV records for discovery, that's fine.  IMAP and outbound SMTP services both lack a defined discovery method other than the ubiquitous "service documentation".  Is there a compelling reason to pick DNS over WF for this?  From the app developer point of view I don't want to have N ways to discover M services.
> 
>-bill
> 
> 
>>
>>________________________________
>>
>>From:Peter Saint-Andre <[e-mail]>
>>To: William Mills <[e-mail]> 
>>Cc: Paul E. Jones <[e-mail]>; 'Cyrus Daboo' <[e-mail]>; "[e-mail]" <[e-mail]> 
>>Sent: Wednesday, June 13, 2012 3:57 PM
>>Subject: Re: [apps-discuss] Aggregated service discovery
>>
>>On 6/13/12 4:54 PM, William Mills wrote:
>>> As I said, I'm interested specifically in IMAP, SMTP and OAuth endpoints. 
>>
>>What exactly is an "endpoint"? A client? An account? A server?
>>
>>> As a data point, DNS SRV records are not controllable in many hosted
>>> domain models.
>>
>>At the last XMPP Summit a few months ago, we learned that DNS SRV
>>records are unavailable in whole countries (e.g., Japan). That doesn't
>>mean we should define a replacement for DNS over HTTP. :)
>>
>>Peter
>>
>>-- 
>>Peter Saint-Andre
>>https://stpeter.im/
>>
>>
>>
>>
>>
>>
>
>