Ok, I tried this with the Op.create and found that it will throw a KeeperException on the first path that doesn't exist. It doesn't return back an OpResult with an "error" type. I can still use this, and just catch the exception and create the node in the exception, but I was under the impression that I could do this in two trips. One trip to get back a list of OpResults from the check that would inform me if the path existed or not, and a second trip to create all the paths that don't exist (and as a note, the CheckResult object doesn't include the path, so I have to infer it from the order of my original list of paths used to create the multi-check).
-Ryan On 2/29/12 7:16 PM, "Ted Dunning" <[email protected]> wrote: >On Wed, Feb 29, 2012 at 7:04 PM, Marshall McMullen < >[email protected]> wrote: > >> Yes, Ted's right. The multi has to fail as that's part of the contract >>it >> guarantees. >> >> The only thing you could do, which will significantly narrow the race >> condition, is as you're *building *the multi, check if the path already >> exists. If so, then don't add the create op for that path into the >>multi. >> Of course this may not work in every situation, but we use that >>approach in >> many code paths and it works well. >> > >Another approach is to compose one multi with Op.exists() for each level >so >that you find everything you need, then create another with the correct >Op.create() operations. That gets the problem down to two server >round-trips but still has the race condition.
