Details
Major Description
Calling mimeSupport.detectMimeTypes for OSX DMG files returns a wrong value.
DMG files are detected as MIME type: "application/zlib" or "application/x-bzip"
instead of expected: "application/x-apple-diskimage".
Error is caused by getSupertype method which returns a wrong type (too "super" MediaType.OCTET_STREAM)for OSX DMG files instead of "application/zlib" or "application/x-bzip"{}{}.
For information, DMG mime type is correctly detected when debugging the method
org/apache/tika/mime/MimeTypes.java:484 public MediaType detect(...
522: MimeType hint = getMimeType(name);
the hint value gets a correct "application/x-apple-diskimage" value here.
But later the hint value is not taken into consideration for possibleTypes as applyHint results:
529: possibleTypes = applyHint(possibleTypes, hint);
This wrong value is returned to :
repository/org/apache/tika/tika-core/1.26/tika-core-1.26-sources.jar!/org/apache/tika/detect/CompositeDetector.java:84
MediaType detected = detector.detect(input, metadata);
if (registry.isSpecializationOf(detected, type)) {
type = detected;
}
Possible solution -Add a more precise Supertype detection for "application/x-apple-diskimage" type
Just add one more verification into the MediaTypeRegistry.getSupertype method, for example, in a 'diff'-like format:
org/apache/tika/tika-core/1.26/tika-core-1.26-sources.jar
org/apache/tika/mime/MediaTypeRegistry.java:187
public MediaType getSupertype(MediaType type) { ... + } else if (type.getSubtype().endsWith("x-apple-diskimage")) { + return MediaType.application("x-bzip"); + } ... }
or
public MediaType getSupertype(MediaType type) { ... + } else if (type.getSubtype().endsWith("x-apple-diskimage")) { + return MediaType.APPLICATION_ZIP; + } ... }
—
Tested at project Sonatype Nexus {{release-3.36.0-01 }}for RAW repository with a "Strict Content Type Validation" set ON when trying to upload *.dmg files.