[DOXIA-543] maven-doxia-markdown fails in parallel builds

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.7
• Fix Version/s: 1.8
• Component/s: Module - Markdown
• Assignee: Michael Osipov
• Reporter: Daniel Wegener
• Created: 16/Aug/16 11:16
• Updated: 04/Feb/17 23:58
• Resolved: 04/Feb/17 22:59

Description

The PegDownProcessor used at https://github.com/apache/maven-doxia/blob/doxia-1.7/doxia-modules/doxia-module-markdown/src/main/java/org/apache/maven/doxia/module/markdown/MarkdownParser.java#L72 is shared between multiple concurrent executions of the maven-site-plugin.

This leads to random errors (NPEs, ClassCastException) because the parser state machine is reused by multiple threads.

It seem not to be enough to make the field non-static since the whole MarkdownParser instance seem to be shared between different threads.

The PegDown Javadoc explicitly states that a PegDownProcessor is not thread-safe: https://github.com/sirthias/pegdown/blob/master/src/main/java/org/pegdown/PegDownProcessor.java

Possible solutions:

• Put the PegDownProcessor into a threadLocal.
• Instanciate the PegDownProcessor in the toHtml method.