[ 
https://issues.apache.org/jira/browse/NIFI-190?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14366611#comment-14366611
 ] 

Joseph Witt commented on NIFI-190:
----------------------------------

Hello - i am going to go ahead and close the PR as-is.  Will leave this ticket 
open though so if someone wants to take the use case and drive toward a 
design/implementation that takes advantage of controller services to enable 
separate Hold/Release processors they can.

Thanks for the contrib.  If you do decide to come back to it we'll be happy to 
work with you on it.  Just don't want to leave PRs lingering and we know we 
want to tackle this a little differently.

> HoldFile processor
> ------------------
>
>                 Key: NIFI-190
>                 URL: https://issues.apache.org/jira/browse/NIFI-190
>             Project: Apache NiFi
>          Issue Type: New Feature
>          Components: Core Framework, Extensions
>            Reporter: Joseph Gresock
>            Priority: Minor
>         Attachments: HoldFile_example.xml
>
>
> Our team has developed a processor for the following use case:
> * Format A needs to be sent to Endpoint A
> * Format B needs to be sent to Endpoint B, but should not proceed until A has 
> reached Endpoint A.  We most commonly have this restriction when Endpoint B 
> requires some output of Endpoint A.
> The proposed HoldFile processor takes 2 types of flow files as input:
> * Files to be held
> * Signal files that can release corresponding held files, based on the value 
> of a configurable "release" attribute
> Signal files are distinguished from held files by the presence of the 
> "flow.file.release.value" attribute.  The processor is configured with a 
> "Release Signal Attribute".  Held files with this attribute whose value 
> matches a received signal value will be released.
> An example:
> HoldFile is configured with Release Signal Attribute = "myId".  Its 'Hold' 
> relationship routes back onto itself.
> 1. flowFile 1 { myId : "123" } enters HoldFile.  It is routed to the 'Hold' 
> relationship
> 2. flowFile 2 { flow.file.release.value : "123" } enters HoldFile.  flowfile 
> 1 is then routed to 'Release', and flow file 2 is removed from the session.
> Signal flow files will also copy their attributes to matching held files, 
> unless otherwise indicated.  This is what allows the output of Endpoint A to 
> pass to Endpoint B, above.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to