My vote is to have a separate namespace for modules. Is it time to introduce org.apache.apex.module.io.fs ?
On Wed, Mar 2, 2016 at 3:25 AM Priyanka Gugale <[email protected]> wrote: > I am planning to put this module in malhar-library project in > package: com.datatorrent.lib.io.fs > Let me know if this is acceptable? > > -Priyanka > > On Tue, Feb 23, 2016 at 6:45 PM, Priyanka Gugale <[email protected] > > > wrote: > > > I haven't created any branch yet, should share it with you as soon as I > > add the code for module. > > Surely would be happy to help :) > > > > -Priyanka > > > > On Tue, Feb 23, 2016 at 6:26 PM, Yogi Devendra <[email protected]> > > wrote: > > > >> Priyanka, > >> > >> Thanks for the update. I will consider these ports during the design > phase > >> of my proposal for HDFS file copy module. > >> > >> I believe you are planning to add this to Apex Malhar. Please post any > >> link > >> / private branch (if any) where I can have a look at the first cut. > >> > >> I will ask for your help if I come across any questions, uncertainties > >> etc. > >> > >> ~ Yogi > >> > >> On 23 February 2016 at 17:59, Priyanka Gugale <[email protected] > > > >> wrote: > >> > >> > I am planning to have following ports to this module: > >> > > >> > Ports > >> > Input port: None > >> > > >> > Output port: > >> > > >> > 1. FileMetadata > >> > 2. BlockMetadata > >> > 3. Block bytes > >> > > >> > -Priyanka > >> > > >> > On Tue, Feb 23, 2016 at 2:16 PM, Yogi Devendra < > [email protected] > >> > > >> > wrote: > >> > > >> > > Priyanka, > >> > > > >> > > Can you please share details about what would be the output ports > from > >> > this > >> > > module? > >> > > > >> > > I am thinking of HDFS File Copy Module which can be used in > >> conjunction > >> > > with this module to copy files from HDFS to HDFS. > >> > > > >> > > ~ Yogi > >> > > > >> > > On 18 February 2016 at 10:29, Mohit Jotwani <[email protected]> > >> > wrote: > >> > > > >> > > > +1 to add this. > >> > > > > >> > > > Regards, > >> > > > Mohit > >> > > > On 17 Feb 2016 23:30, "Pramod Immaneni" <[email protected]> > >> > wrote: > >> > > > > >> > > > > +1 to add this module > >> > > > > > >> > > > > On Wed, Feb 17, 2016 at 9:21 AM, Priyanka Gugale < > >> > > > [email protected] > >> > > > > > > >> > > > > wrote: > >> > > > > > >> > > > > > We need partitions for parallel read but how will the reader > >> > > partition > >> > > > > know > >> > > > > > which offset of the file it should read from. Normally > >> FileSplitter > >> > > > > creates > >> > > > > > this metadata, let's call them as reader task, and forwards > >> them to > >> > > > next > >> > > > > > operator which is block reader. Block reader will receive one > of > >> > the > >> > > > > tasks > >> > > > > > and read from specified offset in file. If FileSplitter is > >> absent > >> > one > >> > > > > > reader partition will have to consume one file entirely, which > >> > means > >> > > we > >> > > > > > can't have parallel reading over one file. I hope this answers > >> your > >> > > > > > question. > >> > > > > > > >> > > > > > Advantage of having this module is having a reusable component > >> made > >> > > up > >> > > > of > >> > > > > > operators which are frequently used together to do file > reading. > >> > > > > > > >> > > > > > -Priyanka > >> > > > > > > >> > > > > > On Wed, Feb 17, 2016 at 11:31 AM, Yogi Devendra < > >> > > > [email protected] > >> > > > > > > >> > > > > > wrote: > >> > > > > > > >> > > > > > > Let me rephrase Ram's question to make it clear: > >> > > > > > > > >> > > > > > > For an application developer using Malhar: > >> > > > > > > What are the advantages / disadvantages of using the > proposed > >> > HDFS > >> > > > File > >> > > > > > > input Module as compared to directly using FileSplitter, > >> > > BlockReader > >> > > > > > > Operators available in Malhar? > >> > > > > > > > >> > > > > > > ~ Yogi > >> > > > > > > > >> > > > > > > On 16 February 2016 at 21:56, Munagala Ramanath < > >> > > [email protected] > >> > > > > > >> > > > > > > wrote: > >> > > > > > > > >> > > > > > > > Can parallel read not be achieved by partitioning ? > >> > > > > > > > > >> > > > > > > > Ram > >> > > > > > > > > >> > > > > > > > On Tue, Feb 16, 2016 at 1:01 AM, Priyanka Gugale < > >> > > > > > > [email protected] > >> > > > > > > > > > >> > > > > > > > wrote: > >> > > > > > > > > >> > > > > > > > > Hi, > >> > > > > > > > > > >> > > > > > > > > It is a common usecase to read big files on HDFS in > >> parallel > >> > > > > fashion > >> > > > > > > i.e. > >> > > > > > > > > many reader thread are used to read the file in > parallel. > >> We > >> > > can > >> > > > > > > achieve > >> > > > > > > > > this on top of Apex using following Malhar operators: > >> > > > > > > > > > >> > > > > > > > > 1. AbstractFileSplitter > >> > > > > > > > > 2. AbstractBlockReader > >> > > > > > > > > > >> > > > > > > > > where FileSplitter, as per file metadata, creates small > >> > reader > >> > > > > > tasks(to > >> > > > > > > > > read file in parts). Those reader tasks are run by > >> > BlockReaders > >> > > > in > >> > > > > > > > parallel > >> > > > > > > > > to read the file. > >> > > > > > > > > > >> > > > > > > > > As these operators are generally used together to > achieve > >> > file > >> > > > read > >> > > > > > > > > operation, I propose we create a module, called > >> > HDFSFileReader > >> > > > for > >> > > > > > > this. > >> > > > > > > > > > >> > > > > > > > > Please provide your suggestions on same. > >> > > > > > > > > > >> > > > > > > > > -Priyanka > >> > > > > > > > > > >> > > > > > > > > >> > > > > > > > >> > > > > > > >> > > > > > >> > > > > >> > > > >> > > >> > > > > >
