ruby - Mongoid; ERROR Mongo::Error::OperationFailure: not authorized for query -

i creating application using ruby/grape , mongoid. when try create or find document in collection using mongoid, example admin.create following error:

error mongo::error::operationfailure: not authorized query on databse.collection 

i can log in mongo console , create/find documents fine credentials use in mongoid.yml.

mongoid.yml:

production:   clients:     default:       database: my_db       hosts:         - myhost:port       username: db_user       password: my_password 

you're format off. try this

production:   clients:     default:       database: my_db       hosts:         - myhost:port       options:         user: db_user         password: my_password 

notice options section , username user