[TIKA-1771] lower magic priority xhtml magic priority to ensure emails detected as message/rfc822

• Type: Improvement
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Fix Version/s: 1.11
• Component/s: detector
• External issue URL: https://github.com/apache/tika/pull/58
• External issue ID: https://github.com/apache/tika/pull/58
• Assignee: Chris A. Mattmann
• Reporter: Jeremy B. Merrill
• Created: 15/Oct/15 20:33
• Updated: 18/Oct/15 19:48
• Resolved: 18/Oct/15 19:21

Description

Emails I have (happy to share if you want) contain XHTML, as one part of a multipart email. Prior to this pull request, the priority on the application/xhtml+xml magic detector was 50, equal to the priority on the message/rfc822 detector. Because of the relative position of the two detectors in tika-mimetypes.xml, the emails were incorrectly detected as XHTML documents.

With this PR, by downgrading the priority of application/xhtml+xml to 40, the more-sensitive email magic detectors take precedence, causing the emails to be properly detected as message/rfc822.

I have not run this thru the govdocs tester or anything other than my own documents, so, full disclosure, this could cause false negative xhtml-detections elsewhere.

I should note this occurs on trunk, from Github, up-to-date as of Tuesday-ish.