class RailsAdmin::CSVConverter

Public Class Methods

new(objects = [], schema = nil) click to toggle source
# File lib/rails_admin/support/csv_converter.rb, line 7
def initialize(objects = [], schema = nil)
  @fields = []
  @associations = []
  schema ||= {}

  return self if (@objects = objects).blank?

  @model = objects.dup.first.class
  @abstract_model = RailsAdmin::AbstractModel.new(@model)
  @model_config = @abstract_model.config
  @methods = [(schema[:only] || []) + (schema[:methods] || [])].flatten.compact
  @fields = @methods.collect { |m| export_field_for(m) }.compact
  @empty = ::I18n.t('admin.export.empty_value_for_associated_objects')
  schema_include = schema.delete(:include) || {}

  @associations = schema_include.each_with_object({}) do |(key, values), hash|
    association = export_field_for(key)
    next unless association&.association?

    model_config = association.associated_model_config
    abstract_model = model_config.abstract_model
    methods = [(values[:only] || []) + (values[:methods] || [])].flatten.compact

    hash[key] = {
      association: association,
      model: abstract_model.model,
      abstract_model: abstract_model,
      model_config: model_config,
      fields: methods.collect { |m| export_field_for(m, model_config) }.compact,
    }
    hash
  end
end

Public Instance Methods

to_csv(options = {}) click to toggle source
# File lib/rails_admin/support/csv_converter.rb, line 41
    def to_csv(options = {})
      if CSV::VERSION == '3.0.2'
        raise <<~MSG
          CSV library bundled with Ruby 2.6.0 has encoding issue, please upgrade Ruby to 2.6.1 or later.
          https://github.com/ruby/csv/issues/62
        MSG
      end

      options = HashWithIndifferentAccess.new(options)
      encoding_to = Encoding.find(options[:encoding_to]) if options[:encoding_to].present?

      csv_string = generate_csv_string(options)
      csv_string = csv_string.encode(encoding_to, invalid: :replace, undef: :replace, replace: '?') if encoding_to

      # Add a BOM for utf8 encodings, helps with utf8 auto-detect for some versions of Excel.
      # Don't add if utf8 but user don't want to touch input encoding:
      # If user chooses utf8, they will open it in utf8 and BOM will disappear at reading.
      # But that way "English" users who don't bother and chooses to let utf8 by default won't get BOM added
      # and will not see it if Excel opens the file with a different encoding.
      csv_string = "\xEF\xBB\xBF#{csv_string}" if encoding_to == Encoding::UTF_8

      [!options[:skip_header], (encoding_to || csv_string.encoding).to_s, csv_string]
    end

Private Instance Methods

export_field_for(method, model_config = @model_config) click to toggle source
# File lib/rails_admin/support/csv_converter.rb, line 67
def export_field_for(method, model_config = @model_config)
  model_config.export.fields.detect { |f| f.name == method }
end
generate_csv_header() click to toggle source
# File lib/rails_admin/support/csv_converter.rb, line 84
def generate_csv_header
  @fields.collect do |field|
    ::I18n.t('admin.export.csv.header_for_root_methods', name: field.label, model: @abstract_model.pretty_name)
  end +
    @associations.flat_map do |_association_name, option_hash|
      option_hash[:fields].collect do |field|
        ::I18n.t('admin.export.csv.header_for_association_methods', name: field.label, association: option_hash[:association].label)
      end
    end
end
generate_csv_row(object) click to toggle source
# File lib/rails_admin/support/csv_converter.rb, line 95
def generate_csv_row(object)
  @fields.collect do |field|
    field.with(object: object).export_value
  end +
    @associations.flat_map do |association_name, option_hash|
      associated_objects = [object.send(association_name)].flatten.compact
      option_hash[:fields].collect do |field|
        associated_objects.collect { |ao| field.with(object: ao).export_value.presence || @empty }.join(',')
      end
    end
end
generate_csv_string(options) click to toggle source
# File lib/rails_admin/support/csv_converter.rb, line 71
def generate_csv_string(options)
  generator_options = (options[:generator] || {}).symbolize_keys.delete_if { |_, value| value.blank? }
  method = @objects.respond_to?(:find_each) ? :find_each : :each

  CSV.generate(**generator_options) do |csv|
    csv << generate_csv_header unless options[:skip_header]

    @objects.send(method) do |object|
      csv << generate_csv_row(object)
    end
  end
end