[HADOOP-6945] Inclusion of Old Jackson-JSON Breaks tasks using Avro (or any task depending on Jackson JSON)

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.21.0
• Assignee: Unassigned
• Reporter: Greg Wittel
• Created: 08/Sep/10 15:41
• Updated: 05/Mar/12 16:50
• Resolved: 05/Mar/12 15:03

Description

HADOOP-6184 added the ability to serialize the Configuration to JSON. However its inclusion of jackson-1.0.1 means that any map-reduce task that depends (directly or indirectly) on Jackson, can only use Jackson 1.0.1 APIs. The 100% fix is to give the task's classpath priority over the core/common classpath (MAPREDUCE-1700/MAPREDUCE-1938) so that a job can use newer revisions of the library.

For a nearer term fix, is it possible to upgrade the included Jackson library to a recent version (1.5.x+)? The APIs are backwards compatible. alernatively, its possible to eliminate the use of Jackson for this minor feature as the Configuration object could be serialized to JSON without a 3rd party library.

An ancilliary issue is that the jackson.version referenced in ivy.xml is never specified in the source tree (ivy/libraries.properties).

Issue Links

• is related to: HADOOP-7606 Upgrade Jackson to version 1.7.1 to match the version required by Jersey
• is related to: HADOOP-7470 move up to Jackson 1.8.8