Module: Sequent::Core::Helpers::UniqueKeys

Included in:
AggregateRoot
Defined in:
lib/sequent/core/helpers/unique_keys.rb

Overview

Some aggregates represent a unique external entity (e.g. a user's email address or login name) and this uniqueness needs to be enforced. For each unique key the returned object should have an entry where the key of the entry describes the scope of the constraint (e.g. user_email or login_name) and the value represents the unique value. Values can be any JSON value (string, object, array, etc). Note that uniqueness is enforced across all aggregate types if the same scope is used.

An AggregateKeyNotUniqueError is raised if a unique constrained is violated when committing the events to the database.

Defined Under Namespace

Modules: ClassMethods

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.included(host_class) ⇒ Object 



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# File 'lib/sequent/core/helpers/unique_keys.rb', line 75

def self.included(host_class)
  host_class.extend(ClassMethods)
end

Instance Method Details

#unique_keys ⇒ Object

Returns the unique keys for the current instance based on the unique_key defintions. You can also override it if you need more compicated logic.

Example return value:

{
  user_email: { email: '[email protected]' }
}



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# File 'lib/sequent/core/helpers/unique_keys.rb', line 65

def unique_keys
  return {} if self.class.unique_key_definitions.nil?

  self.class.unique_key_definitions
    &.transform_values do |attributes|
      attributes.transform_values { |block| instance_exec(&block) }.compact
    end
    &.delete_if { |_, value| value.empty? }
end