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https://issues.apache.org/jira/browse/FLUME-1425?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13491133#comment-13491133
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Mike Percy commented on FLUME-1425:
-----------------------------------

Rather than @Ignore the test on commit, I posted a small patch to FLUME-1681 to 
disable the unit test for now.
                
> Create a SpoolDirectory Source and Client
> -----------------------------------------
>
>                 Key: FLUME-1425
>                 URL: https://issues.apache.org/jira/browse/FLUME-1425
>             Project: Flume
>          Issue Type: Improvement
>            Reporter: Patrick Wendell
>            Assignee: Patrick Wendell
>             Fix For: v1.3.0
>
>         Attachments: FileProcessingSource.java, 
> FLUME-1425.avro-conf-file.txt, FLUME-1425.patch.v1.txt, 
> FLUME-1425.v5.patch.txt, FLUME-1425.v6.patch.txt, FLUME-1425.v6.patch.txt, 
> FLUME-1425.v7.patch.txt, FLUME-1425.v8.patch.txt
>
>
> The proposal is to create a small executable client which reads logs from a 
> spooling directory and sends them to a flume sink, then performs cleanup on 
> the directory (either by deleting or moving the logs). It would make the 
> following assumptions
> - Files placed in the directory are uniquely named
> - Files placed in the directory are immutable
> The problem this is trying to solve is that there is currently no way to do 
> guaranteed event delivery across flume agent restarts when the data is being 
> collected through an asynchronous source (and not directly from the client 
> API). Say, for instance, you are using a exec("tail -F") source. If the agent 
> restarts due to error or intentionally, tail may pick up at a new location 
> and you lose the intermediate data.
> At the same time, there are users who want at-least-once semantics, and 
> expect those to apply as soon as the data is written to disk from the initial 
> logger process (e.g. apache logs), not just once it has reached a flume 
> agent. This idea would bridge that gap, assuming the user is able to copy 
> immutable logs to a spooling directory through a cron script or something.
> The basic internal logic of such a client would be as follows:
> - Scan the directory for files
> - Chose a file and read through, while sending events to an agent
> - Close the file and delete it (or rename, or otherwise mark completed)
> That's about it. We could add sync-points to make recovery more efficient in 
> the case of failure.
> A key question is whether this should be implemented as a standalone client 
> or as a source. My instinct is actually to do this as a source, but there 
> could be some benefit to not requiring an entire agent in order to run this, 
> specifically that it would become platform independent and you could stick it 
> on Windows machines. Others I have talked to have also sided on a standalone 
> executable.

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