Class: Operations::Components::Preconditions

Inherits:
Prechecks show all
Defined in:
lib/operations/components/preconditions.rb

Overview

We check all the precondition failures to return all the codes to the user at once. This provides a better UX, user is able to fix everything at once instead of getting messages one by one. This is similar to the idea of validations.

Precondition can return a Symbol - it will be used as an error code. If String is returned - it will be used as a message itself. Please avoid returning string, use i18n instead. Hash with ‘:error` key will be also treated as a failure ans used accordingly. Also, `Failure` monad gets unwrapped and the value follows the rules above. Also, it is possible to return an array of failures.

Successful preconditions returns either nil or an empty array or a ‘Success` monad.

Constant Summary

Constants inherited from Base

Base::DEFAULT_NAMES_MAP, Base::MONADS_DO_WRAPPER_SIGNATURES

Instance Method Summary collapse

Methods inherited from Prechecks

#callable?, #required_context

Instance Method Details

#call(params, context) ⇒ Object 



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# File 'lib/operations/components/preconditions.rb', line 20

def call(params, context)
  failures = callable.flat_map do |entry|
    results = Array.wrap(entry.call(**context))
    results.filter_map { |result| result_failure(result) }
  end

  result(
    params: params,
    context: context,
    errors: errors(normalize_failure(failures))
  )
end