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From Cameron McKenzie <mckenzie....@gmail.com>
Subject Re: How to watch on descendant znodes using Curator PathCache?
Date Mon, 10 Feb 2014 02:55:15 GMT
That author would be me, sorry I haven't got back to you Jordan, just been
flat out with work. I believe that some additional unit tests were
required, which I haven't got a chance to look at yet.

Check, the patch is attached to the Jira ticket if you want to give it a
spin. I'll eventually get around to writing some additional unit tests, but
I'm not sure when that will be, so more than happy for you to look into it
if you've got time.
cheers
Cam


On Mon, Feb 10, 2014 at 1:42 PM, Check Peck <comptechgeeky@gmail.com> wrote:

> Sure Jordan. Let me take a look into that. In the meantime, is there any
> workaround for this for now which I can try it out or if you have any
> example which I can take a look?
>
>
> On Sun, Feb 9, 2014 at 6:41 PM, Jordan Zimmerman <
> jordan@jordanzimmerman.com> wrote:
>
>> Sorry - I thought you were using NodeCache. There's already an issue to
>> add recursive support to PathChildrenCache:
>> https://issues.apache.org/jira/browse/CURATOR-33 - I'm waiting for the
>> author of the patch to respond to some comments. Maybe you can take on this
>> issue as I haven't heard back from him..
>>
>> -JZ
>>
>> ------------------------------
>> From: Check Peck Check Peck <comptechgeeky@gmail.com>
>> Reply: Check Peck comptechgeeky@gmail.com
>> Date: February 9, 2014 at 9:35:24 PM
>> To: Jordan Zimmerman jordan@jordanzimmerman.com
>> Subject:  Re: How to watch on descendant znodes using Curator PathCache?
>>
>> Thanks for suggestion. I am using PathChildrenCache for one level. For
>> example -
>>
>> If my root node is - "/my/test" and I am keeping a watch on that node
>> using the PathChildrenCache as mentioned in my previous email code. So
>> suppose if these nodes gets added to my root node -
>>
>>     "/my/test/test1"
>>     "/my/test/test2"
>>     "/my/test/test3"
>>
>> Then I get notified and it works fine with the PathChildrenCache code but
>> if any new node gets added, updated or removed to `"/my/test/test1"`,
>> `"/my/test/test2"` and `"/my/test/test3"` then it doesn't works and no
>> watches gets triggered and I am not able to understand how to make that
>> work as my understanding is very limited as of now.
>>
>>
>>
>> On Sun, Feb 9, 2014 at 6:31 PM, Jordan Zimmerman <
>> jordan@jordanzimmerman.com> wrote:
>>
>>>  Do you need just the one level? If so, why not use PathChildrenCache:
>>> http://curator.apache.org/curator-recipes/path-cache.html
>>>
>>>  -JZ
>>>
>>>  ------------------------------
>>> From: Check Peck Check Peck <comptechgeeky@gmail.com>
>>> Reply: user@curator.apache.org user@curator.apache.org
>>> Date: February 9, 2014 at 9:08:20 PM
>>> To: user user@curator.apache.org
>>> Subject:  How to watch on descendant znodes using Curator PathCache?
>>>
>>>  I am working on a project in which I need to maintain a watches on a
>>> node, and that nodes children as well. I have tried using PathCache but I
>>> am not sure how to watch for childrens children here?
>>>
>>> Here my root node is - `"/my/test"` and I am keeping a watch on that
>>> node using the below code. What I want to do is, to keep the watch on
>>> `"/my/test"` znode. So suppose if these nodes gets added to my root node -
>>>
>>>     "/my/test/test1"
>>>     "/my/test/test2"
>>>     "/my/test/test3"
>>>
>>> Then I should get notified (till this part I am able to make it work)
>>> but if any new node gets added, updated or removed to `"/my/test/test1"`,
>>> `"/my/test/test2"` and `"/my/test/test3"` then I should also get notified
>>> and this is the part I am not able to understand how to make it work.
>>>
>>> Whenever I am adding any new node to `"/my/test"` such as
>>> `"/my/test/test1"`, `"/my/test/test2"`, `"/my/test/test3"` then the watch
>>> gets triggered with the use of below code. But if I am adding any new node
>>> to `"/my/test/test1"` or `"/my/test/test2"`, then no watches get triggerd
>>> and I am not sure how to add the code for that as well? Any thoughts how
>>> this can be done?
>>>
>>> May be if somebody has done this in the past.. So any example will be of
>>> great help to me..
>>>
>>> Below is my code which works fine for `"/my/test"` children but not the
>>> childrens of `"/my/test/test1"` and etc etc.
>>>
>>>     private static final String PATH = "/my/test";
>>>
>>>     public static void main(String[] args) {
>>>         CuratorFramework client = null;
>>>         PathChildrenCache cache = null;
>>>         try {
>>>             client = CuratorClient.createSimple("localhost:2181");
>>>             client.start();
>>>
>>>             // in this example we will cache data. Notice that this is
>>> optional.
>>>             cache = new PathChildrenCache(client, PATH, true);
>>>             cache.start();
>>>
>>>             addListener(cache);
>>>
>>>             for(;;) {
>>>                 try {
>>>                     Thread.sleep(50000);
>>>                 } catch(InterruptedException e) {
>>>                 }
>>>             }
>>>         } catch (Exception e1) {
>>>             e1.printStackTrace();
>>>         }
>>>     }
>>>
>>> Below is my addListener method -
>>>
>>>     private static void addListener(PathChildrenCache cache) {
>>>
>>>         PathChildrenCacheListener listener = new
>>> PathChildrenCacheListener() {
>>>             public void childEvent(CuratorFramework client,
>>> PathChildrenCacheEvent event) throws Exception {
>>>                 switch (event.getType()) {
>>>                 case CHILD_ADDED: {
>>>                     System.out.println("Node added: " +
>>> ZKPaths.getNodeFromPath(event.getData().getPath()));
>>>                     break;
>>>                 }
>>>
>>>                 case CHILD_UPDATED: {
>>>                     System.out.println("Node changed: "    +
>>> ZKPaths.getNodeFromPath(event.getData().getPath()));
>>>                     break;
>>>                 }
>>>
>>>                 case CHILD_REMOVED: {
>>>                     System.out.println("Node removed: "    +
>>> ZKPaths.getNodeFromPath(event.getData().getPath()));
>>>                     break;
>>>                 }
>>>                 default:
>>>                     break;
>>>                 }
>>>             }
>>>         };
>>>         cache.getListenable().addListener(listener);
>>>     }
>>>
>>> Can anyone provide a simple example for this for my use case? I am using
>>> Curator 2.4.0 which got released recently.
>>>
>>>
>>
>

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