module Traject::Macros::Marc21
Some of these may be generic for any MARC, but we haven't done the analytical work to think it through, some of this is def specific to Marc21
.
Constants
- EXTRACT_ALL_MARC_VALID_OPTIONS
- EXTRACT_MARC_VALID_OPTIONS
A list of symbols that are valid keys in the options hash
- SERIALZED_MARC_VALID_OPTIONS
Public Class Methods
Side-effect the accumulator with the options
# File lib/traject/macros/marc21.rb, line 115 def self.apply_extraction_options(accumulator, options, translation_map=nil) only_first = options[:first] trim_punctuation = options[:trim_punctuation] default_value = options[:default] allow_duplicates = options[:allow_duplicates] if only_first accumulator.replace Array(accumulator[0]) end if translation_map translation_map.translate_array! accumulator end if trim_punctuation accumulator.collect! {|s| Marc21.trim_punctuation(s)} end unless allow_duplicates accumulator.uniq! end if options.has_key?(:default) && accumulator.empty? accumulator << default_value end end
A macro that will extract data from marc according to a string field/substring specification.
First argument is a string spec suitable for the MarcExtractor
, see Traject::MarcExtractor::Spec
.
Second arg is optional options, including options valid on MarcExtractor.new
, and others. By default, will de-duplicate results, but see :allow_duplicates
-
:allow_duplicates => boolean, default false, if set to true then will avoid
de-duplicating the result array (array.uniq!)
-
:separator: (default ' ' (space)), what to use when joining multiple subfield matches from same field. Set to `nil` to leave them as separate values (which is actually default if only one subfield is given in spec, like `100a`). See
MarcExtractor
docs for more info. -
:alternate_script: (default true). True, automatically include 'alternate script' MARC 880 linked fields corresponding to matched specifications. `false`, do not include. `:only` include only linked 880s corresponding to spec, not base tags.
## Soft-Deprecated options: post-processing transformations
These don't produce a deprecation warning and there is no planned horizon for them to go away, but the alternative of using additional transformation macros (from Traject::Macros::Transformation
) composed with extract_marc
is recommended.
-
:first => true: take only first value. Instead, use `extract_marc(whatever), first_only`
-
:translation_map => String: translate with named translation map looked up in load
path, uses Tranject::TranslationMap.new(translation_map_arg). **Instead**, use `extract_marc(whatever), translation_map(translation_map_arg)`
-
:trim_punctuation => true; trims leading/trailing punctuation using standard algorithms that
have shown themselves useful with Marc, using Marc21.trim_punctuation. **Instead**, use `extract_marc(whatever), trim_punctuation`
-
:default => String: if otherwise empty, add default value. Instead, use `extract_marc(whatever), default(“default value”)`
Examples:
to_field("title"), extract_marc("245abcd"), trim_punctuation to_field("id"), extract_marc("001"), first_only to_field("geo"), extract_marc("040a", :separator => nil), translation_map("marc040")
If you'd like extract_marc
functionality but you're not creating an indexer step, see Traject::Macros::Marc21.extract_marc_from
module method.
# File lib/traject/macros/marc21.rb, line 62 def extract_marc(spec, options = {}) # Raise an error if there are any invalid options, indicating a # misspelled or illegal option, using a string instead of a symbol, etc. unless (options.keys - EXTRACT_MARC_VALID_OPTIONS).empty? raise RuntimeError.new("Illegal/Unknown argument '#{(options.keys - EXTRACT_MARC_VALID_OPTIONS).join(', ')}' in extract_marc at #{Traject::Util.extract_caller_location(caller.first)}") end # We create the TranslationMap and the MarcExtractor here # on load, so the lambda can just refer to already created # ones, and not have to create a new one per-execution. # # Benchmarking shows for MarcExtractor at least, there is # significant performance advantage. if translation_map_arg = options.delete(:translation_map) translation_map = Traject::TranslationMap.new(translation_map_arg) else translation_map = nil end extractor = Traject::MarcExtractor.new(spec, options) lambda do |record, accumulator, context| accumulator.concat extractor.extract(record) Marc21.apply_extraction_options(accumulator, options, translation_map) end end
Convenience method when you want extract_marc
behavior, but NOT to create a lambda for an Indexer
step, but instead just give it a record directly and get back an array of values.
array = Traject::Indexer::Marc21.extract_marc_from(record, "245ab", :trim_punctuation => true)
If you have a Traject::Indexer::Context
and want to pass it in, you can:
array = Traject::Indexer::Marc21.extract_marc_from(record, "245ab", :trim_punctuation => true, :context => existing_context)
# File lib/traject/macros/marc21.rb, line 104 def self.extract_marc_from(record, spec, options = {}) output = [] # Nil context works, but if caller wants to pass one in # for better error reporting that's cool too. context = options.delete(:context) || nil extract_marc(spec, options).call(record, output, context) return output end
# File lib/traject/macros/marc21.rb, line 273 def self.first!(arr) # kind of esoteric, but slice used this way does mutating first, yep arr.slice!(1, arr.length) end
Trims punctuation mostly from end, and occasionally from beginning of string. Not nearly as complex logic as SolrMarc's version, just pretty simple.
Removes
-
trailing: comma, slash, semicolon, colon (possibly preceded and followed by whitespace)
-
trailing period if it is preceded by at least three letters (possibly preceded and followed by whitespace)
-
single square bracket characters if they are the start and/or end chars and there are no internal square brackets.
Returns altered string, doesn't change original arg.
# File lib/traject/macros/marc21.rb, line 252 def self.trim_punctuation(str) # If something went wrong and we got a nil, just return it return str unless str # trailing: comma, slash, semicolon, colon (possibly preceded and followed by whitespace) str = str.sub(/ *[ ,\/;:] *\Z/, '') # trailing period if it is preceded by at least three letters (possibly preceded and followed by whitespace) str = str.sub(/( *[[:word:]]{3,})\. *\Z/, '\1') # single square bracket characters if they are the start and/or end # chars and there are no internal square brackets. str = str.sub(/\A\[?([^\[\]]+)\]?\Z/, '\1') # trim any leading or trailing whitespace str.strip! return str end
Public Instance Methods
Takes the whole record, by default from tags 100 to 899 inclusive, all subfields, and adds them to output. Subfields in a record are all joined by space by default.
options
- :from
-
default '100', only tags >= lexicographically
- :to
-
default '899', only tags <= lexicographically
- :separator
-
how to join subfields, default space, nil means don't join
All fields in from-to must be marc DATA (not control fields), or weirdness
Can always run this thing multiple times on the same field if you need non-contiguous ranges of fields.
# File lib/traject/macros/marc21.rb, line 213 def extract_all_marc_values(options = {}) unless (options.keys - EXTRACT_ALL_MARC_VALID_OPTIONS).empty? raise RuntimeError.new("Illegal/Unknown argument '#{(options.keys - EXTRACT_ALL_MARC_VALID_OPTIONS).join(', ')}' in extract_all_marc at #{Traject::Util.extract_caller_location(caller.first)}") end options = {:from => "100", :to => "899", :separator => ' '}.merge(options) if [options[:from], options[:to]].map{|x| x.is_a? String}.any?{|x| x == false} raise ArgumentError.new("from/to options to extract_all_marc_values must be strings") end lambda do |record, accumulator, context| record.each do |field| next unless field.tag >= options[:from] && field.tag <= options[:to] subfield_values = field.subfields.collect {|sf| sf.value} next unless subfield_values.length > 0 if options[:separator] accumulator << subfield_values.join( options[:separator]) else accumulator.concat subfield_values end end end end
Serializes complete marc record to a serialization format. required param :format, serialize_marc(:format => :binary)
formats:
- xml
-
MarcXML
- json
-
marc-in-json (dilettantes.code4lib.org/blog/2010/09/a-proposal-to-serialize-marc-in-json/)
- binary
-
Standard ISO 2709 binary marc. By default WILL be base64-encoded, assumed destination a solr 'binary' field.
-
add option `:binary_escape => false` to do straight binary – unclear
what Solr's documented behavior is when you do this, and add a string with binary control chars to solr. May do different things in diff Solr versions, including raising exceptions.
-
add option `:allow_oversized => true` to pass that flat
to the MARC::Writer. Oversized records will then still be serialized, with certain header bytes filled with ascii 0's – technically illegal MARC, but can still be read by ruby MARC::Reader in permissive mode.
-
# File lib/traject/macros/marc21.rb, line 174 def serialized_marc(options) unless (options.keys - SERIALZED_MARC_VALID_OPTIONS).empty? raise RuntimeError.new("Illegal/Unknown argument '#{(options.keys - SERIALZED_MARC_VALID_OPTIONS).join(', ')}' in seralized_marc at #{Traject::Util.extract_caller_location(caller.first)}") end format = options[:format].to_s binary_escape = (options[:binary_escape] != false) allow_oversized = (options[:allow_oversized] == true) raise ArgumentError.new("Need :format => [binary|xml|json] arg") unless %w{binary xml json}.include?(format) lambda do |record, accumulator, context| case format when "binary" binary = MARC::Writer.encode(record, allow_oversized) binary = Base64.encode64(binary) if binary_escape accumulator << binary when "xml" accumulator << MARC::FastXMLWriter.encode(record) when "json" accumulator << JSON.dump(record.to_hash) end end end
A transformation macro version of trim_punctuation
– heuristics for trimming punctuation from AACR2/MARC style values, to get bare values.
# File lib/traject/macros/marc21.rb, line 144 def trim_punctuation lambda do |rec, accumulator| accumulator.collect! {|s| Marc21.trim_punctuation(s)} end end
Private Instance Methods
A macro that will extract data from marc according to a string field/substring specification.
First argument is a string spec suitable for the MarcExtractor
, see Traject::MarcExtractor::Spec
.
Second arg is optional options, including options valid on MarcExtractor.new
, and others. By default, will de-duplicate results, but see :allow_duplicates
-
:allow_duplicates => boolean, default false, if set to true then will avoid
de-duplicating the result array (array.uniq!)
-
:separator: (default ' ' (space)), what to use when joining multiple subfield matches from same field. Set to `nil` to leave them as separate values (which is actually default if only one subfield is given in spec, like `100a`). See
MarcExtractor
docs for more info. -
:alternate_script: (default true). True, automatically include 'alternate script' MARC 880 linked fields corresponding to matched specifications. `false`, do not include. `:only` include only linked 880s corresponding to spec, not base tags.
## Soft-Deprecated options: post-processing transformations
These don't produce a deprecation warning and there is no planned horizon for them to go away, but the alternative of using additional transformation macros (from Traject::Macros::Transformation
) composed with extract_marc
is recommended.
-
:first => true: take only first value. Instead, use `extract_marc(whatever), first_only`
-
:translation_map => String: translate with named translation map looked up in load
path, uses Tranject::TranslationMap.new(translation_map_arg). **Instead**, use `extract_marc(whatever), translation_map(translation_map_arg)`
-
:trim_punctuation => true; trims leading/trailing punctuation using standard algorithms that
have shown themselves useful with Marc, using Marc21.trim_punctuation. **Instead**, use `extract_marc(whatever), trim_punctuation`
-
:default => String: if otherwise empty, add default value. Instead, use `extract_marc(whatever), default(“default value”)`
Examples:
to_field("title"), extract_marc("245abcd"), trim_punctuation to_field("id"), extract_marc("001"), first_only to_field("geo"), extract_marc("040a", :separator => nil), translation_map("marc040")
If you'd like extract_marc
functionality but you're not creating an indexer step, see Traject::Macros::Marc21.extract_marc_from
module method.
# File lib/traject/macros/marc21.rb, line 62 def extract_marc(spec, options = {}) # Raise an error if there are any invalid options, indicating a # misspelled or illegal option, using a string instead of a symbol, etc. unless (options.keys - EXTRACT_MARC_VALID_OPTIONS).empty? raise RuntimeError.new("Illegal/Unknown argument '#{(options.keys - EXTRACT_MARC_VALID_OPTIONS).join(', ')}' in extract_marc at #{Traject::Util.extract_caller_location(caller.first)}") end # We create the TranslationMap and the MarcExtractor here # on load, so the lambda can just refer to already created # ones, and not have to create a new one per-execution. # # Benchmarking shows for MarcExtractor at least, there is # significant performance advantage. if translation_map_arg = options.delete(:translation_map) translation_map = Traject::TranslationMap.new(translation_map_arg) else translation_map = nil end extractor = Traject::MarcExtractor.new(spec, options) lambda do |record, accumulator, context| accumulator.concat extractor.extract(record) Marc21.apply_extraction_options(accumulator, options, translation_map) end end