Class: Delineate::Serializers::CsvSerializer

Inherits:
MapSerializer show all
Defined in:
lib/delineate/serializers/csv_serializer.rb

Overview

AttributeMap serializer that handles CSV as the external data format.

Instance Method Summary collapse

Methods inherited from MapSerializer

#initialize

Constructor Details

This class inherits a constructor from Delineate::MapSerializer

Instance Method Details

#serializable_header(prefix = '') ⇒ Object

Returns the header row as an array of strings, one for each mapped attribute, including nested assoications. The items appear in the array in the same order as their corresponding attribute values.



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# File 'lib/delineate/serializers/csv_serializer.rb', line 76

def serializable_header(prefix = '')
  returning(serializable_header = serializable_attribute_names) do
    serializable_header.map! {|h| headerize(prefix + h.to_s)}

    add_includes(:one_to_one) do |association, record, opts|
      assoc_map = association_attribute_map(association)
      assoc_prefix = prefix + association.to_s + '_'
      serializable_header.concat self.class.new(record, assoc_map, opts).serializable_header(assoc_prefix)
    end

    add_includes(:one_to_many) do |association, records, opts|
      assoc_map = association_attribute_map(association)
      assoc_prefix = prefix + association.to_s.singularize + '_'
      serializable_header.concat self.class.new(records.first, assoc_map, opts).serializable_header(assoc_prefix)
    end
  end
end

#serializable_record(prefix = [], top_level = true) ⇒ Object

Returns the record’s mapped attributes in the serializer’s “internal” format. For this class the representation is an array of one or more rows, one row for each item in teh record’s has_many collections. Each row is an array of values ordered as follows:

1. All the record's mapped attributes in map order.
2. All one-to-one mapped association attributes in map order.
3. All one-to-many mapped association attributes in map order

Do not specify any method parameters when calling serializable_record.



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# File 'lib/delineate/serializers/csv_serializer.rb', line 49

def serializable_record(prefix = [], top_level = true)
  new_rows = []

  prefix += serializable_attribute_names.map do |name|
    @attribute_map.attribute_value(@record, name)
  end

  add_includes(:one_to_one) do |association, record, opts, nil_record|
    assoc_map = association_attribute_map(association)
    prefix, new_rows = self.class.new(record, assoc_map, opts).serializable_record(prefix, false)
  end

  add_includes(:one_to_many) do |association, records, opts, nil_record|
    assoc_map = association_attribute_map(association)
    records.each do |r|
      p, next_rows = self.class.new(r, assoc_map, opts).serializable_record(prefix, false)
      new_rows << (next_rows.empty? ? p : next_rows) unless nil_record
    end
  end

  top_level ? (new_rows << prefix if new_rows.empty?; new_rows) : [prefix, new_rows]
end

#serialize(options = {}) ⇒ Object

Returns the record’s mapped attributes as a CSV string. If you specify a truthy value for the :include_header option, the CSV header is output as the first line.

See the description in serializable_record for the order of the attributes.



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# File 'lib/delineate/serializers/csv_serializer.rb', line 15

def serialize(options = {})
  opts = options[:include_header] ?
    {:write_headers => true, :headers => serializable_header, :encoding => "UTF-8"} :
    {:encoding => "UTF-8"}

  opts = remove_serializer_class_options(options).merge(opts)
  opts.delete(:include_header)

  CSV.generate(opts) do |csv|
    serializable_record.each {|r| csv << r}
  end
end

#serialize_header(options = {}) ⇒ Object

Returns the header row as a CSV string.



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# File 'lib/delineate/serializers/csv_serializer.rb', line 29

def serialize_header(options = {})
  opts = {:encoding => "UTF-8"}.merge(remove_serializer_class_options(options))
  CSV.generate_line(serializable_header, opts)
end

#serialize_in(csv_string, options = {}) ⇒ Object

Not implemented yet.



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# File 'lib/delineate/serializers/csv_serializer.rb', line 35

def serialize_in(csv_string, options = {})
  raise "Serializing from CSV is not supported at this time. You can inherit a class from CsvSerializer to write a custom importer."
end