Class: Metacrunch::Marcxml::Document

Inherits:
Object
  • Object
show all
Defined in:
lib/metacrunch/marcxml/document.rb,
lib/metacrunch/marcxml/document/subfield.rb,
lib/metacrunch/marcxml/document/datafield.rb,
lib/metacrunch/marcxml/document/controlfield.rb,
lib/metacrunch/marcxml/document/subfield_set.rb,
lib/metacrunch/marcxml/document/datafield_set.rb

Defined Under Namespace

Classes: Controlfield, Datafield, DatafieldSet, Subfield, SubfieldSet

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Document

Returns a new instance of Document.



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# File 'lib/metacrunch/marcxml/document.rb', line 11

def initialize
  @controlfields_map = {}
  @datafields_map    = {}
end

Instance Method Details

#[](query_string) ⇒ Array<String>

Returns a control field value or data field/sub field values matching the given query string.

Parameters:

  • query_string (String) —

    a query string.

Returns:

  • (Array<String>) —

    The sub field values matching the query. Is empty if no match is found.



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# File 'lib/metacrunch/marcxml/document.rb', line 100

def [](query_string)
  # Control field query
  if query_string.starts_with?("00")
    # Example: "005"
    # [0..2] => Control field tag
    tag = query_string[0..2].presence
    controlfield(tag)&.value

  # Data field / sub field query
  else
    # Example: "100**a,e"
    # [0..2] => Data field tag (required).
    # [3]    => Ind1, defaults to `*`, which matches any indicator 1 (optional). ` `, `-` or `_` will be interpreted as `blank`.
    # [4]    => Ind2, defaults to `*`, which matches any indicator 2 (optional). ` `, `-` or `_` will be interpreted as `blank`.
    # [5]    => Sub field code(s) (optional).
    tag      = query_string[0..2].presence

    ind1     = query_string[3].presence
    ind1     = nil    if ind1 == "*"
    ind1     = :blank if ind1 == "-" || ind1 == "_" || ind1 == " "

    ind2     = query_string[4].presence
    ind2     = nil    if ind2 == "*"
    ind2     = :blank if ind2 == "-" || ind2 == "_" || ind2 == " "

    subfield_codes = query_string[5..-1]&.split(",")&.map(&:strip).compact.presence

    datafields(tag, ind1: ind1, ind2: ind2).subfields(subfield_codes).values
  end
end

#controlfield(tag) ⇒ Metacrunch::Marcxml::Document::Controlfield?

Returns the control field matching the given tag or nil if a control field with the given tag does not exist.

Parameters:

  • tag (String, Integer) —

    the tag of the control field. The tag can be a string or an integer.

Returns:



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# File 'lib/metacrunch/marcxml/document.rb', line 33

def controlfield(tag)
  @controlfields_map[normalize_tag(tag)]
end

#datafields(tag = nil, ind1: nil, ind2: nil) ⇒ Metacrunch::Marcxml::Document::DatafieldSet

Returns the data fields matching the given tag(s) and/or ind1/ind2.

Parameters:

  • tag (String, Integer, #each, nil) (defaults to: nil) —

    filter by tag(s). Can be nil to match all data fields. The tag can be a string or an integer. To filter for more than a single tag, tag also accepts any object that responds to #each like Array and Range.

  • ind1 (nil, String, Array<String>) (defaults to: nil) —

    filter by indicator 1. Can be nil to match any indicator.

  • ind2 (nil, String, Array<String>) (defaults to: nil) —

    filter by indicator 2. Can be nil to match any indicator.

Returns:



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# File 'lib/metacrunch/marcxml/document.rb', line 63

def datafields(tag = nil, ind1: nil, ind2: nil)
  matched_datafields = if tag.nil?
    @datafields_map.values.flatten(1)
  elsif tag.is_a?(Enumerable)
    tag.map{ |_tag| @datafields_map[normalize_tag(_tag)] }.compact.flatten(1)
  else
    @datafields_map[normalize_tag(tag)]
  end

  matched_datafields = (matched_datafields || []).select do |datafield|
    match_indicator(ind1, datafield.ind1) && match_indicator(ind2, datafield.ind2)
  end

  DatafieldSet.new(matched_datafields)
end

#empty? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/metacrunch/marcxml/document.rb', line 16

def empty?
  @controlfields_map.blank? && @datafields_map.blank?
end