[ http://issues.apache.org/jira/browse/HADOOP-619?page=comments#action_12457431 ] Doug Cutting commented on HADOOP-619: -------------------------------------
> change the signature of InputFormatBase.areValidInputDirectories() to return > a list of valid Paths I don't think we should do this, since it assumes that inputs are always representable by Paths. The long-term goal is that inputs and outputs are only assumed to be (1) specifiable in a Configuration and (2) representable as a serializeable Split implementation. In particular, we should not assume that they are FileSystem files, and hence should not pass Path in a primitive MapReduce API. Thus areValidInputDirectories(Path[]) should evolve into hasValidInput(JobConf), but not as a part of this patch. > Otherwise we will need to expand the globs twice For now, I think the glob can happen twice: once when checking the input in the JobClient, and once on the JobTracker when constructing splits. Longer term we may wish to try to optmize this, but I'm not convinced that's required. If it is required, then perhaps, instead of hasValidInput(JobConf) we could have a prepareInput(JobConf) method that validates inputs and is permitted to alter the job. But we shouldn't modify the InputFormat API for this issue. Owen's already working on that separately. > Unify Map-Reduce and Streaming to take the same globbed input specification > --------------------------------------------------------------------------- > > Key: HADOOP-619 > URL: http://issues.apache.org/jira/browse/HADOOP-619 > Project: Hadoop > Issue Type: Improvement > Components: mapred > Reporter: eric baldeschwieler > Assigned To: Sanjay Dahiya > Attachments: Hadoop-619.patch, Hadoop-619.patch, Hadoop-619.patch > > > Right now streaming input is specified very differently from other map-reduce > input. It would be good if these two apps could take much more similar input > specs. > In particular -input in streaming expects a file or glob pattern while MR > takes a directory. It would be cool if both could take a glob patern of > files and if both took a directory by default (with some patern excluded to > allow logs, metadata and other framework output to be safely stored). > We want to be sure that MR input is backward compatible over this change. I > propose that a single file should be accepted as an input or a single > directory. Globs should only match directories if the paterns is '/' > terminated, to avoid massive inputs specified by mistake. > Thoughts? -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira
