[AVRO-1262] Provide access to the writer schema from the mapper

• Type: New Feature
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.7.4
• Component/s: java
• Assignee: Doug Cutting
• Reporter: Josh Spiegel
• Created: 27/Feb/13 19:50
• Updated: 07/Aug/13 19:24

Description

When using an Avro InputFormat like AvroKeyInputFormat, the writer schema of the container file should be accessible from the mapper. This is useful in cases where a reader schema is not specified.

A workaround is to use FileSplit#getPath() to access the container file and manually pull out the schema. This workaround is not ideal because internally the writer schema has already been read (see AvroRecordReaderBase#createAvroFileReader(...)) - it is awkward and inefficient for the user to repeat this work.

See also:
http://mail-archives.apache.org/mod_mbox/avro-user/201302.mbox/%3CCAOF3b61nFw4ztOo9Q5pHHtoUDFZ3sRrvEdRGbXGV_cscTqd5LA%40mail.gmail.com%3E