mongodb/mongoid · error · Mongoid::Errors::NoClientsConfig

No clients configuration provided.

Error message

No clients configuration provided.

What it means

Error "No clients configuration provided." thrown in mongodb/mongoid.

Source

Thrown at lib/mongoid/config.rb:527

    #
    # @return [ true | false ] If the app is deployed on Passenger.
    #
    # @deprecated
    def running_with_passenger?
      @running_with_passenger ||= defined?(PhusionPassenger)
    end

    Mongoid.deprecate(self, :running_with_passenger?)

    private

    def set_log_levels
      Mongoid.logger.level = Mongoid::Config.log_level unless defined?(::Rails)
      Mongo::Logger.logger.level = Mongoid.logger.level
    end

    def clients=(clients)
      raise Errors::NoClientsConfig.new unless clients

      c = clients.with_indifferent_access
      Validators::Client.validate(c)
      @clients = c
    end

    # Get database client that respects global overrides
    # Config.override_database and Config.override_client.
    #
    # @return [Mongo::Client] Client according to global overrides.
    def global_client
      client = if Threaded.client_override
                 Clients.with_name(Threaded.client_override)
               else
                 Clients.default
               end
      if Threaded.database_override
        client.use(Threaded.database_override)

View on GitHub (pinned to 0da0e23d71)

When it happens

Trigger: Thrown at lib/mongoid/config.rb:527 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of mongodb/mongoid@0da0e23d71 (2026-08-23). Data as JSON: /api/errors/ea75cda1eccb45c9. Report an issue: GitHub.