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List:       avro-user
Subject:    Re: Deserialize with different schema
From:       Mehrez Alachheb <mehrez () adomik ! com>
Date:       2015-08-13 9:52:01
Message-ID: 0C021B82-55B7-48E3-AA89-6B14FCFE9402 () adomik ! com
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Thanks Julian for your reply,
 Yes  with GenericRecord i can deserialise my data easily.

Mehrez.
 
> On 13 Aug 2015, at 10:49, julianpeeters <julianpeeters@gmail.com> wrote:
> 
> Hi Mehrez,
> 
> Can I guess? You're reading some Python/Pig AvroStorage output? Hate that.
> 
> I get the same error when the reader schema has a namespace but the writer
> has none. But only when a record is in a union.
> 
> 
> Here's a pair of small runnable  examples
> <https://github.com/julianpeeters/avro-namespace-issues/tree/master/reading>  
> that show errors with reading and writing accross namespaces.
> 
> For the sake of being complete, here's my  question
> <http://apache-avro.679487.n3.nabble.com/Issues-reading-and-writing-namespace-less-schemas-from-namespaced-Specific-Records-td4032092.html> \
>  , and it looks like Vitaly Gordon ran into this issue as well,  here
> <http://apache-avro.679487.n3.nabble.com/Unable-to-compile-a-namespace-less-schema-td4028318.html> \
>                 
> . 
> 
> IHMO this is a bug that hinders Avro's utility as a data interchange format.
> I don't think the technical issue is in trying to import a class from the
> default package (which succeeds outside of unions), but instead it's from
> trying to resolve a union reflectively and the writer schema's fullname
> doesn't match the class' fullname.
> 
> The fix for now:
> You could try using the Generic API instead, and then map the Generic
> Records to your Specific Records manually. Here's a start in Java:
> 
> import org.apache.avro.Schema;
> import org.apache.avro.file.DataFileReader;
> import org.apache.avro.generic.GenericDatumReader;
> import org.apache.avro.generic.GenericRecord;
> 
> GenericDatumReader<GenericRecord> datumReader = new
> GenericDatumReader<>(schema);
> DataFileReader<GenericRecord> fileReader = new
> DataFileReader<>(file, datumReader);
> GenericRecord record = fileReader.next();
> 
> 
> Cheers,
> Julian
> 
> 
> 
> --
> View this message in context: \
> http://apache-avro.679487.n3.nabble.com/Deserialize-with-different-schema-tp4032782p4032816.html
>  Sent from the Avro - Users mailing list archive at Nabble.com.


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