Skip to main content

Plone addon to fix Archetypes file field mimetypes

Project description

This Plone add-on can be used to update broken mimetypes of Blob fields.

When a file or an image is uploaded to a Blob field, its mimetype is computed based on information from the mimetypes_registry.

If that registry misses some information, the computed mimetype can be wrong or too general.

For instance, prior to version 2.0.7 of Products.MimetypeRegistry, the default mimetypes_registry of a Plone portal did not know of OpenXML mimetypes. Those files would get application/zip mimetype instead of their proper mimetypes.

As computation of mimetype happens only at load time, upgrading Products.MimetypeRegistry is not enough to fix broken mimetypes.

The function collective.updatemimetype.migrate walks over content, looks for blob fields that would get different mimetype if they would be uploaded again, and updates those field mimetypes. It can be called from a GenericSetup upgrade step with:

from collective.updatemimetype import migrate



The update can demand a lot of memory and take a long time if your portal holds a lot of content.

If you want to limit migration to specific content items, you can pass a query argument to the migrate function. For instance, while the code above updates both File and Image content items of a default Plone site, the code below would only update File content items:

from collective.updatemimetype import migrate

catalog_query = {'portal_type': 'File'}

migrate(portal, catalog_query)

There is also a view registered on the portal. Call it with:


The view can also be called with a query parameter. To limit update to File items, call the view with:




0.1.2 (2015-07-06)

  • Fix limiting update to the results of a catalog query. And document how to do it. [gotcha]

0.1.1 (2015-06-30)

  • Fix classifier [gotcha]

0.1 (2015-06-29)

  • Initial release. [gotcha]

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution (27.9 kB view hashes)

Uploaded source

Supported by

AWS AWS Cloud computing Datadog Datadog Monitoring Facebook / Instagram Facebook / Instagram PSF Sponsor Fastly Fastly CDN Google Google Object Storage and Download Analytics Huawei Huawei PSF Sponsor Microsoft Microsoft PSF Sponsor NVIDIA NVIDIA PSF Sponsor Pingdom Pingdom Monitoring Salesforce Salesforce PSF Sponsor Sentry Sentry Error logging StatusPage StatusPage Status page