Parameter list too long in initialize method

Question

I have an initialize method for a class that looks like this:

def initialize(
 site:,
 name:,
 date_online: '-',
 date_offline: '-',
 date_modified: '-',
 date_tagged: '-',
 tags: []
)
 @site = site
 @name = name
 @date_online = date_online
 @date_offline = date_offline
 @date_modified = date_modified
 @date_tagged = date_tagged
 @tags = tags
end

However, RuboCop is telling me that I should:

Metrics/ParameterLists: Avoid parameter lists longer than 5 parameters. [7/5]

So, what is the best way to rectify this? It's an initializer, so all those parameters are necessary. Is the desired solution to use a hash?

def initialize(args)
 @site = args[:site]
 @name = args[:name]
 @date_online = args[:date_online] || '-'
 @date_offline = args[:date_offline] || '-'
 @date_modified = args[:date_modified] || '-'
 @date_tagged = args[:date_tagged] || '-'
 @tags = args[:tags] || []
end

Then how should I manually handle the fact that site and name are required? I could add some code after the assignments that will throw an error if the required fields aren't present:

raise ArgumentError unless @site && @name

That makes sense to me. But I assume the makers of RuboCop know what they're talking about, which leads me to suspect that there's a standard for this sort of thing.

• Heslacher: I have rolled back your last edit. Please do not update the code in your question to incorporate feedback from answers, doing so goes against the Question + Answer style of Code Review. This is not a forum where you should keep the most updated version in your question. Please see what you may and may not do after receiving answers .

Answer 1

An in-between solution for you might be:

def initialize(site:, name:, **options)
 @site = site
 @name = name
 @date_online = options[:date_online] || '-'
 @date_offline = options[:date_offline] || '-'
 @date_modified = options[:date_modified] || '-'
 @date_tagged = options[:date_tagged] || '-'
 @tags = options[:tags] || []
end

You would probably want to raise an error if an unexpected key was passed in as part of options.

• Nossidge: That's great! I didn't realise you could split up parameters like that! This has helped me a lot, thank you.
• Emile Vrijdags: Thx, but now I have Cyclomatic complexity for initialize is too high. [7/6] lol! Hmm, maybe have a hash with default values, then loop through that default hash, and assign to options if key doesn't exist or something.. might not improve readability though :o
• David Aldridge: @EmileVrijdags personally I take a cyclomatic complexity warning with a pinch of salt. If the code is easily understood by future maintainers, then I'll disable it for that method.