Please upgrade to at least Mongoid 7.0 and Ruby 2.5.
Due to the library not being updated, mongoid_paranoia is no longer supported.
Neither _slugs nor slugs default to an empty Array and nil slugs are allowed since a sparse index is used. Previously a confusing Mongo::Error::OperationFailure: E11000 duplicate key error index error was raised on the second record with an empty set of slugs inserted into the database.
You should unset _slugs for any documents that have an empty array value.
Klass.where(_slugs: []).unset(:_slugs)
Klass.where(_slugs: nil).unset(:_slugs)See #225 for more information.
The :sparse option on the _slugs index is now set in all cases. The :unique option is set except in an edge case with Paranoid documents.
See #172 and #227 for more information.
MongoDB has a default limit around 1KB to the size of the index keys and will raise error 17280, key too large to index when trying to create a record that causes an index key to exceed that limit. MongoDB 2.4 did not enforce this limit (see mongodb#SERVER-5290). MongoDB 2.6 corrected this. Slugs of the form text[-number] and the text portion is limited in size to Mongoid::Slug::MONGO_INDEX_KEY_LIMIT_BYTES - 32 bytes since mongoid-slug 5.2. To restore old behavior, change the constant in your code or set the limit for each model to nil. This can be useful when running MongoDB with failIndexKeyTooLong set to false, however be advised that MongoDB will make those documents impossible to find when the index is used. Note that setting this limit for exsiting data has no effect on such data.
See mongoid-slug#204 for more information.
The underscored gem name, mongoid_slug, has been deprecated. Use the hyphenated version, mongoid-slug.
If you are upgrading to Mongoid Slug 1.0.0 please migrate in accordance with the instructions in https://github.com/mongoid/mongoid-slug/wiki/How-to-upgrade-to-1.0.0-or-newer. Mongoid Slug 1.0.0 stores the slugs in a single field _slugs of array type, and all previous slugs must be migrated.