Cannot set expiration time for lists

[leoncruz]

I'm creating a list of items with an expiration time, but, I'm having the following error:

irb>> Kredis.list "mylist", expires_in: 1.minute
kredis-1.5.0/lib/kredis/types.rb:62:in `list': unknown keyword: :expires_in (ArgumentError)

[nzwsch]

https://github.com/rails/kredis/blob/main/lib/kredis/types.rb#L64-L66

def list(key, default: nil, typed: :string, config: :shared, after_change: nil)
  type_from(List, config, key, after_change: after_change, default: default, typed: typed)
end

It appears that some kredis types do not support expires_in.
If this is not simply a typo, there may be a reason for this.

[leoncruz]

@nzwsch Yes, I have to do a little trick to expire work:

1. First add the parameter:

module Kredis::Types
  def list(key, typed: :string, config: :shared, after_change: nil, expires_in: nil)
    type_from(List, config, key, after_change: after_change, typed: typed, expires_in: expires_in)
  end

  def unique_list(key, typed: :string, limit: nil, config: :shared, after_change: nil, expires_in: nil)
    type_from(UniqueList, config, key, after_change: after_change, typed: typed, limit: limit, expires_in: expires_in)
  end
end

2. Override the Kredis list to set the expiration time on key when first value is set:

class Kredis::Types::List < Kredis::Types::Proxying
  proxying :lrange, :lrem, :lpush, :ltrim, :rpush, :exists?, :del, :expire

  attr_accessor :typed, :expires_in

  def prepend(*elements)
    return unless elements.flatten.any?

    l = lpush types_to_strings(elements, typed)

    set_expire

    l
  end

  def append(*elements)
    return unless elements.flatten.any?

    r = rpush types_to_strings(elements, typed)

    set_expire

    r
  end
  alias << append

  private

  attr_accessor :expire_at

  def set_expire
    return unless expires_in

    if expired?
      @expire_at = expires_in.from_now

      expire expires_in
    end
  end

  def expired?
    !expire_at || expire_at.past?
  end
end

I have to do the same with hash type too. Would be nice to have this behavior in the Kredis itself

[jeremy]

Pull request welcome 🤗