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https://issues.apache.org/jira/browse/CRUNCH-677?focusedWorklogId=201490&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-201490
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ASF GitHub Bot logged work on CRUNCH-677:
-----------------------------------------

                Author: ASF GitHub Bot
            Created on: 20/Feb/19 18:05
            Start Date: 20/Feb/19 18:05
    Worklog Time Spent: 10m 
      Work Description: ben-roling commented on pull request #19: CRUNCH-677 
Source and Target accept FileSystem
URL: https://github.com/apache/crunch/pull/19
 
 
   The change to Source, Target, and SourceTarget obviously breaks 
compatibility for implementors of these interfaces as we're still building 
against Java 7 so I can't provide a default implementation for these new 
methods.
   
   Also, there is an expectation that Target implementations will need to 
update the asSourceTarget() method to copy the FileSystem along.
 
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Issue Time Tracking
-------------------

            Worklog Id:     (was: 201490)
            Time Spent: 10m
    Remaining Estimate: 0h

> Support passing FileSystem to File Sources and Targets
> ------------------------------------------------------
>
>                 Key: CRUNCH-677
>                 URL: https://issues.apache.org/jira/browse/CRUNCH-677
>             Project: Crunch
>          Issue Type: Improvement
>          Components: Core
>            Reporter: Ben Roling
>            Assignee: Josh Wills
>            Priority: Major
>          Time Spent: 10m
>  Remaining Estimate: 0h
>
> We'd like to pass a FileSystem instance to File Sources and Targets to fully 
> qualify the Path.  Without the FileSystem, the Pipeline doesn't necessarily 
> have enough information to understand the Path.  In particular, when the Path 
> is an HA HDFS path like "hdfs://my-cluster/data", the Pipeline might not have 
> the 
> [configuration|https://hadoop.apache.org/docs/current/hadoop-project-dist/hadoop-hdfs/HDFSHighAvailabilityWithNFS.html#Configuration_details]
>  to resolve "hdfs://my-cluster".
> While it is in some cases possible to seed the Pipeline configuration with 
> all the HDFS properties necessary to communicate with any HDFS HA cluster the 
> Pipeline might talk to, it can be awkward and/or difficult to do this in all 
> cases.  We have cases where we'd like not to have to know all of the clusters 
> upfront.
> With the proposed change, code like the following is possible, where 
> {{readFileSystem}} and {{writeFileSystem}} are external FileSystems 
> synthesized from Configuration completely separate from that used to 
> construct the Pipeline itself:
> {code}
> Configuration emptyConfiguration = new Configuration(false);
> Pipeline pipeline = new MRPipeline(getClass(), emptyConfiguration);
> FileSystem readFileSystem = ...;
> PCollection<String> data = 
> pipeline.read(From.textFile("hdfs://my-cluster-1/data", readFileSystem));
> FileSystem writeFileSystem = ...;
> pipeline.write(data, To.textFile("hdfs://my-cluster-2/output", 
> writeFileSystem));
> {code}
> Note: the hdfs://my-cluster-1 and hdfs://my-cluster-2 parts of the paths 
> would not strictly need to be included as they would be implied by the 
> FileSystem instances passed in the calls.  As such the paths could simply be 
> passed as "/data" and "/output" with equivalent behavior.



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