[NIFI-5689] ReplaceText does not handle end of line correctly on buffer boundary

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.7.1
• Component/s: Extensions
• Assignee: Otto Fowler
• Reporter: Sergei Zhirikov
• Created: 12/Oct/18 08:12
• Updated: 26/Oct/18 13:33
• Resolved: 26/Oct/18 13:33

Description

ReplaceText appears to misbehave under the following conditions:

• The input flow file contains text with Windows-style line endings (CR-LF).
• ReplaceText is configured to perform "Regex Replace" in "Line-by-Line" mode.
• The "Maximum Buffer Size" is set to a value smaller than the whole file content,
  but large enough to fit any of the text lines in the file.
• A CR-LF pair of characters in one of the lines happens to be split across two buffers,
  that is CR is the last character in one buffer and LF is the first one in the following one.

An example flow template is attached to illustrate the problem.

In the example, the regular expression is intended to remove white space at the end of each line. It operates as expected in all lines except the third one (containing "GHI"). That line satisfies the conditions described above. As a result the CR character in the end of the line is removed, which does not happen in other lines.
In some more complicated cases both CR and LF end up being removed, effectively resulting in two lines being joined into one. Although, I haven't managed to create a simple test case to reproduce that.

Issue Links

• is superceded by: NIFI-5711 NLKBufferedReader appears extend and copy portions of the JDK BufferedReader
• links to: GitHub Pull Request #3084