---------- Forwarded message ---------- From: Adam Rosien <a...@rosien.net> Date: Mon, Jan 11, 2010 at 10:27 AM Subject: Re: blog post about zk and group membership To: zookeeper-u...@hadoop.apache.org
Yes, your Disqus comment went through. We filed a ticket with them about some javascript issues that messed up the UI. Data wrappers would certainly work but I feel like it's still a black-hole to fall into that something like node-metadata (to do something like HTTP's Content-Type") would help solve. That too can be a black hole :(. I need more practical experience to find the right balance. .. Adam On Mon, Jan 11, 2010 at 10:20 AM, Patrick Hunt <ph...@apache.org> wrote: > Adam Rosien wrote: >> >> Re "off the shelf", my title of "Actually Implementing" was a *bit* >> snarky to try and gain some readers, but it wasn't intended to be >> sharp criticism; more documented recipes is a good thing for everyone. >> I'd be happy to submit a JIRA with a group membership recipe. >> > > Ya, I got that, no worries. It was a valid point and something I've been > asked before. Figured I could get some (addl) free work out of the deal. ;-) > > Disqus seems to be having troubles, I've tried like 3 times to comment on > your blog post, did it finally make it through? > >> Re zkclient, I agree that documentation is a big thing, which I hope >> to help out with as I use it more. I'm talking now with one of the >> developers about zkclient's implementation of data serialization since >> that is another big area; zk pushes all serialization semantics into >> the clients, which is ok but requires its own practical strategies. > > Yea, that's an interesting point. I suspect that a wrapper around the data > (zk contrib? subclass/proxy of ZooKeeper?) that put content-type type > information into the "header" of the data portion might be useful. The > wrapper could encode/decode based on the data type in ZK, vs the data type > the user would like. The wrapper could support whichever encode/decode the > user would like (say xml/json to start) etc... Donno how useful in general > but in a larger system with a bunch of heterogeneous clients accessing it > might be interesting. > > Patrick > >> >> On Mon, Jan 11, 2010 at 9:49 AM, Patrick Hunt <ph...@apache.org> wrote: >>> >>> Adam, this is awesome! I've retweeted it on my twitter account: >>> http://twitter.com/phunt/status/7637054275 >>> >>> A few comments: >>> >>> 1) you are correct about the "off the shelf" part, but really alot of >>> that >>> is our marketing blurb, we paint with a broad stroke. I think it would >>> make >>> sense to include this sort of detail in the "recipes" page though, would >>> you >>> be interested to create a JIRA and submit some content? (you could re >>> purpose alot of what you have in your post) >>> >>> 2) re zkclient - I have not been following that project closely of late, >>> however Mahadev and I did review their code a few months ago. At that >>> time >>> we had some concerns about the semantic impact of some of the design >>> choices >>> they made (which were fine, just not well documented and therefor easy >>> for >>> users to miss). In particular (again, at the time, may be addressed by >>> now) >>> watch notifications could be lost during disconnected/expired sessions, >>> and >>> the user would not be made aware of this. >>> >>> 3) excellent point/suggestion on the "rogue" service >>> >>> Patrick >>> >>> Adam Rosien wrote: >>>> >>>> I've written a blog post about using ZooKeeper for group membership at >>>> KaChing: >>>> >>>> http://bit.ly/6yraP6 >>>> >>>> http://eng.kaching.com/2010/01/actually-implementing-group-management.html >>>> >>>> Any comments or feedback is welcome. >>>> >>>> .. Adam >
