bensheldon/good_job · error · ArgumentError

Invalid cron format: '#{cron}'

Error message

Invalid cron format: '#{cron}'

What it means

Error "Invalid cron format: '#{cron}'" thrown in bensheldon/good_job.

Source

Thrown at app/models/good_job/cron_entry.rb:64

      GoodJob::Job
        .select("lateral_jobs.*")
        .from(from_clause)
        .joins(join_clause)
        .index_by(&:cron_key)
    end

    def self.find(key, configuration: nil)
      all(configuration: configuration).find { |entry| entry.key == key.to_sym }.tap do |cron_entry|
        raise ActiveRecord::RecordNotFound unless cron_entry
      end
    end

    def initialize(params = {})
      @params = params

      return if cron_proc?
      raise ArgumentError, "Invalid cron format: '#{cron}'" unless fugit.instance_of?(Fugit::Cron)
    end

    def key
      params.fetch(:key)
    end

    alias id key
    alias to_param key

    def job_class
      params.fetch(:class)
    end

    def set
      params[:set]
    end

    def args

View on GitHub (pinned to 5fcde48f87)

Solutions

1. Verify the cron string in your `config.good_job.cron` entry is a valid cron expression accepted by fugit (e.g. "0 * * * *" or natural forms like "every day at midnight").
2. Check for typos: missing or extra fields, unsupported characters, or out-of-range values (minute 0-59, hour 0-23, day of month 1-31, month 1-12, day of week 0-6).
3. If you need custom scheduling logic instead of a cron string, pass a `cron_proc` lambda; the format check is skipped for procs.
4. Test the expression in a Rails console with `Fugit::Cron.parse(your_cron_string)`; it must return a Fugit::Cron instance, not nil.

Example fix

# config/initializers/good_job.rb
Rails.application.configure do
  config.good_job.cron = {
    my_task: {
      # was "0 0 * *" (too few fields) or another invalid expression
      cron: "0 0 * * *",
      class: "MyJob"
    }
  }
end

When it happens

Trigger: Thrown at app/models/good_job/cron_entry.rb:64 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of bensheldon/good_job@5fcde48f87 (2026-08-23). Data as JSON: /api/errors/cabd4b26dd1b81f4. Report an issue: GitHub.