Retry replicaset.Initiate

Retry replicaset.Initiate

Another attempt at retrying replicaset
initiation. The change I made in
https://codereview.appspot.com/98670045/
does not work well, as the error from
replSetInitiate may be spurious; it is
possible to receive an error despite the
config being written.

https://code.launchpad.net/~axwalk/juju-core/initiate-replicaset-retry/+merge/221475

(do not edit description out of merge proposal)

[axw, 2014-05-30 00:38:46]

Please take a look.

[wallyworld, 2014-05-30 00:43:43]

I'd prefer if we didn't have to do a string equality check for the error. Can we
fix that before landing?

https://codereview.appspot.com/102000044/diff/1/replicaset/replicaset.go
File replicaset/replicaset.go (right):

https://codereview.appspot.com/102000044/diff/1/replicaset/replicaset.go#newc...
replicaset/replicaset.go:29: rsMembersUnreachableError = "all members and seeds
must be reachable to initiate set"
I'd like to think there's a error code we can check. I think we can cast the
error to a mongo error struct and look at the error code? Like is done for
IsUnauthorized() in testing/mgo.go

[axw, 2014-05-30 01:33:39]

On 2014/05/30 00:43:43, wallyworld wrote:
> I'd prefer if we didn't have to do a string equality check for the error. Can
we
> fix that before landing?
> 
> https://codereview.appspot.com/102000044/diff/1/replicaset/replicaset.go
> File replicaset/replicaset.go (right):
> 
>
https://codereview.appspot.com/102000044/diff/1/replicaset/replicaset.go#newc...
> replicaset/replicaset.go:29: rsMembersUnreachableError = "all members and
seeds
> must be reachable to initiate set"
> I'd like to think there's a error code we can check. I think we can cast the
> error to a mongo error struct and look at the error code? Like is done for
> IsUnauthorized() in testing/mgo.go

AFAICT there is no corresponding error code for this error.
Even in testing/mgo.go, isUnauthorized has to resort to comparing error strings.

[wallyworld, 2014-05-30 01:35:28]

LGTM