MIME Types

To find out what MIME types that are currently registered and active within a SkyVault installation, you can use an admin Web Script. This is available at http://localhost:8080/alfresco/service/mimetypes. This will list all the currently registered MIME types, and provide a details link for each one. Selecting the details link will then show metadata extractors, and which transformations are currently supported both to and from that MIME type, and by what transformer.

For example, you will see something like this for the ZIP MIME type:

application/zip - zip
   Extractors: org.alfresco.repo.content.metadata.TikaAutoMetadataExtracter
   Transformable To:
      application/xhtml+xml = org.alfresco.repo.content.transform.ArchiveContentTransformer
      text/html = org.alfresco.repo.content.transform.ArchiveContentTransformer
      text/plain = org.alfresco.repo.content.transform.ArchiveContentTransformer
      text/xml = org.alfresco.repo.content.transform.ArchiveContentTransformer
   Transformable From:
      Cannot be generated from anything else

So it is quite easy to find out if a MIME type is known to the SkyVault system, if there are any metadata extractors for it, to what formats it can be transformed, and from what formats it can be generated.

Lets say you wanted to add a transformer that can transform XML documents to PDF files based on XSL-FO (XSL formatting objects). SkyVault does not currently know about formatting object files (.fo) so we would need to add a new MIME type for this. To do this create an XML file with the following content:

<alfresco-config area="mimetype-map">
  <config evaluator="string-compare" condition="Mimetype Map">
    <mimetypes>
      <mimetype mimetype="text/xsl" display="XSL-FO">
        <extension>fo</extension>
      </mimetype>
    </mimetypes>
  </config>
</alfresco-config>

Call the file custom-mimetype-map.xml and put it in tomcat/shared/classes/alfresco/extension/mimetype. If we access the mimetype Web Script we should see the following for the newly registered MIME type:

text/xsl - fo
   No extractors
   Transformable To:text/plain = org.alfresco.repo.content.transform.StringExtractingContentTransformer
   Transformable From: Cannot be generated from anything else

The .fo files themselves will by default be transformable to text, which means that they will be indexed and searchable without having to add a custom transformer. But to actually use the formatting objects to transform XML files into PDF files you would have to add a custom transformer. Out of the box it will use the following transformer:

text/xml - xml
   Extractors: org.alfresco.repo.content.metadata.TikaAutoMetadataExtracter
   Transformable To:
      application/eps = Complex via: application/pdf
      application/pdf = org.alfresco.repo.content.transform.TextToPdfContentTransformer
      . . .

• tomcat/shared/classes/alfresco/extension/mimetype - add a custom-mimetype-map.xml file with the new MIME type definitions

• repo-amp/src/main/amp/config/alfresco/module/repo-amp/mimetype-map-custom.xml - MIME Type definitions (note. the file name has to be this)

• Sample configuration for adding a MIME type

• Adding a custom MIME type