[DRILL-7293] Convert the regex ("log") plugin to use EVF

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.16.0
• Fix Version/s: 1.17.0
• Assignee: Paul Rogers
• Reporter: Paul Rogers
• Reviewer: Arina Ielchiieva
• Created: 13/Jun/19 00:49
• Updated: 15/Jul/19 10:27
• Resolved: 15/Jul/19 10:27

Description

The "log" plugin (which uses a regex to define the row format) is the subject of Chapter 12 of the Learning Apache Drill book (though the version in the book is simpler than the one in the master branch.)

The recently-completed "Enhanced Vector Framework" (EVF, AKA the "row set framework") gives Drill control over the size of batches created by readers, and allows readers to use the recently-added provided schema mechanism.

We wish to use the log reader as an example for how to convert a Drill format plugin to use the EVF so that other developers can convert their own plugins.

This PR provides the first set of log plugin changes to enable us to publish a tutorial on the EVF.

Issue Links

• links to: GitHub Pull Request #1807