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Zookeeper, mail # user - Error in zookeeper recipes documention of " Leader Election"

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Error in zookeeper recipes documention of " Leader Election"
nileader 2012-09-11, 01:13

   About “Leader Election”part of zookeeper recipes documention(
of my colleagues are confused on this: "Otherwise, watch for changes on
"ELECTION/guid-n_j", where j is the smallest sequence number such that j <
i and n_j is a znode in C;"

   In my course, I tell them that in this using case, just watch the node
that only smaller than you, And the meaning of the expression here is

   I think the document is error。
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2012/9/8 Ben Bangert <[EMAIL PROTECTED]>

> As I was implementing read-only mode in the Python client based on the
> Java client patch, I noticed a rather odd naming for the error you get if
> you send a modification command to a read-only
> server...NotReadOnlyException.
> Why the sudden change in error context?
> For reference, here's some of the other errors that Zookeeper may return
> when making an API call:
> NoNode
> NoAuth
> BadVersion
> NoChildrenForEphemerals
> NodeExists
> NotEmpty
> So the explanation for these errors are consistent, "your API call cannot
> be completed because of this state on the server". Personally, I'm a huge
> fan of consistency in an API, so these are all great. But then with
> NotReadOnly, we have an error that is not referring to the state of the
> server (that it *is* ReadOnly), but one that refers to the semantics of the
> API call itself. Given all the other errors, I was really expecting the
> server to throw a ReadOnly error indicating your call cannot be completed
> due to that state on the server (like the others).
> Was there a reason for the context switch in error naming? I understand
> given its been merged in for almost 2 years now that there's unlikely to be
> any switch to make it consistent in context with the other errors, but it
> might be nice for future feature additions to try and document or enforce
> better consistency in the API.
> Cheers,
> Ben