[AVRO-1352] Schema for fixed types corrupted when writing out in JSON format

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.7.0, 1.7.1, 1.7.2, 1.7.3, 1.7.4
• Fix Version/s: 1.7.7
• Component/s: c++
• Labels: patch,
• Assignee: Unassigned
• Reporter: Steve Roehrs
• Created: 08/Jul/13 01:55
• Updated: 24/Jul/14 20:16
• Resolved: 29/Jun/14 18:30

Description

A change made in NodeImpl.cc under AVRO-1026 has introduced a bug that corrupts JSON schemas when writing them to disk or dumping to a stream. This manifested when using DataFileWriter to generate a data file, and the schema stored in the header was corrupted from the original schema provided.

e.g

This:

{
  “type”: “fixed”,
  “name”: “Unsigned16”,
  “size”: 2
}

Becomes this:

{
  “type”: “fixed”,
  “size”: 2,
  “name” : “Unsigned16”,
}

Note the extraneous comma after the ‘name’ attribute.
The bug exists for Avro 'fixed' types, and has not been observed for other types. A test case will be developed.

The bug can be fixed by simply re-ordering the code in NodeFixed::printJson.