marcjs

marcjs

MARC record Node.js library

Getting Started

Install the module with: npm install marcjs

const { Marc, Record } = require('marcjs');
let record = new Record();
record.append(['245', ' 1', 'a', 'Middlemarch /', 'b', 'Georges Eliot.']);
console.log(record.as('Text'));
console.log(Marc.format(record, 'Marcxml'));

Usage

This script reads an ISO2709 file, adds a field to each record, and writes each record into an ISO2709 file, a MARCXML file, a JSON file, and a text file.

const { Marc } = require('marcjs');
const fs = require('fs');

const input = fs.createReadStream('BNF-Livres-01.mrc');
const parser = Marc.createStream('Iso2709', 'Parser');
let trans = Marc.transform((record) => {
  // Delete 9.. tags and add a 801 field
  record.fields = record.fields.filter((field) => field[0][0] !== '9');
  record.append( [ '801', '  ', 'a', 'Tamil s.a.r.l.', 'b', '2021-01-01' ] );
});
const transStream = input.pipe(parser).pipe(trans);
// Pipe the stream of transformed biblio record to 4 different writers
['marcxml', 'iso2709', 'json', 'mij', 'text'].forEach((type) => {
  const output = fs.createWriteStream(`bib-edited.${type}`);
  const formater = Marc.createStream(type, 'Formater');
  formater.pipe(output);
  transStream.pipe(formater)
});
const tick = setInterval(() => { console.log(reader.count); }, 100);
input.on('end', () => {
  console.log("Number of processed biblio records: " + reader.count);
  clearInterval(tick);
});

Marc object

The Marc object has two properties:

• parser
• formater

Marc has three functions:

• createStream()
• parse()
• transform()

Marc properties

The class has two properties defining the serialization formats that MARC module is able to read and write.

• parser -- The serialization format that MARC can read: Iso2709, Marcxml, and MiJ (MARC-in-JSON).
• formater --The serialisation format that MARC can write: Iso2709, Marcxml, MiJ, Text, Json.

const knownParser = Object.keys(Marc.parser);
console.log(knownParser); // Display Marc format that marcjs can parse

Marc functions

createStream(type, what)

Returns a duplex stream for specific serialization formats. The stream has a property count containing the number of records handled. The type is the type of serialization format: ISO2709, Marcxml, Json, MiJ. The what is the type of action the stream is doing: Parser ou Formater.

• A parser receives data from a nodejs Stream and produces objects of type Record.
• A formater receives Record objects and send them to a nodejs Stream.

Usage:

const iso2709Parser = Marc.createStream('Iso2709', 'Parser');
const marcxmlParser = Marc.createStream('Marcxml', 'Parser');
const textFormater = Marc.createStream('Text', 'Formater'); 

Read an ISO2709 file and display its text version to the screen:

const { Marc } = require('marcjs');
const fs = require('fs');
const input = fs.createReadStream('bib.mrc');
const parser = Marc.createStream('Iso2709', 'Parser');
const formater = Marc.createStream('Text', 'Formater');
input.pipe(parser).pipe(formater).pipe(process.stdout);

One-liner version:

const { Marc } = require('marcjs');
const fs = require('fs');
fs.createReadStream('bib.mrc')
  .pipe(Marc.createStream('Iso2709', 'Parser'))
  .pipe(Marc.createStream('Text', 'Formater'))
  .pipe(process.stdout);

Version with marcjs Duplex Node.js classes:

const { Iso2709Parser, TextFormater } = require('marcjs');
fs.createReadStream('bib.mrc')
    .pipe(new Iso2709Parser())
    .pipe(new TextFormater)
    .pipe(process.stdout);

parse(raw, type)

Parse a raw record serialized in type format, and returns a MARC record.

For example:

const { Marc } = require('marcjs');
const marcxml = `<record>
<leader>01288nam  2200337   450 </leader>
<controlfield tag="001">FRBNF345958660000005</controlfield>
<datafield tag="200" ind1="1" ind2=" ">
 <subfield code="a">Histoire religieuse du Maine</subfield>
 <subfield code="b">Texte imprimé</subfield>
</datafield>
</record>`;
const record = Marc.parse(marcxml, 'marcxml');

format(record, type)

Format record with type serialization format. Note that:

For example:

const { Marc } = require('marcjs);
// Get a MARC record
console.log(Marc.format(record, 'Text'));
console.log(Marc.format(record, 'Marcxml'));

transform(function)

Returns a Transform stream transforming a MARC record. It allows chaining reading, multiple transformation, writing, via piping streams.

Example:

const deleteSomeFields = Marc.transform((record) => {
  record.delete('8..');
  record.delete('6..');
});
... get a record
record = deleteSomeFields(record);

Record Class

The Record object has two attributes :

• leader
• fields

And Record has several methods:

• append()
• as()
• get()
• match()
• delete()
• clone()
• mij()

Record attributes

The library manipulates MARC biblio records as native Javascript objects which have two attributes: leader and fields. Each record is a Record object.

Example:

{
  "leader": "01243nam  22002173n 450 ",
  "fields": [
    [
      "001",
      "FRBNF323046990000009"
    ],
    [
      "009",
      "http://catalogue.bnf.fr/ark:/12148/cb32304699p"
    ],
    [
      "035",
      "  ",
      "a",
      "SAFIG04210003-01"
    ],
    [
      "039",
      "  ",
      "o",
      "CRI",
      "a",
      "SU063312260001S  "
    ],
    [
      "100",
      "  ",
      "a",
      "19970701d1927    m  y0frey0103    ba"
    ],
    [
      "101",
      "0 ",
      "a",
      "eng"
    ],
    [
      "102",
      "  ",
      "a",
      "GB"
    ],
    [
      "105",
      "  ",
      "a",
      "||||z   00|||"
    ],
    [
      "106",
      "  ",
      "a",
      "r"
    ],
    [
      "200",
      "1 ",
      "a",
      "Greek printing types",
      "b",
      "Texte imprimé",
      "e",
      ", 1465-1927, facsimiles from an exhibition of books illustrating the development of Greek printing shown in the British Museum, 1927. With an historical introduction by Victor Scholderer. [Preface by Frederic G. Kenyon.]"
    ],
    [
      "210",
      "  ",
      "a",
      "London, British Museum ; B. Quaritch ; H. Milford",
      "a",
      "(Oxford, printed by J. Johnson)",
      "d",
      "1927. Gr. in-fol. (390 x 265), 23 p., fac-sim. [Don 217025] -Ia-"
    ],
    [
      "300",
      "  ",
      "a",
      "On a joint des comptes rendus extraits du ¸Times Lit. Suppl.¸, 25 August. 1927 et du ¸Library association record¸, 1927, et ¸La première Renaissance des études grecques en France, hellénistes et imprimeurs¸, par Egger, extrait de la ¸Revue de Paris¸, 15 décembre 1868"
    ],
    [
      "702",
      " |",
      "3",
      "12331862",
      "a",
      "Kenyon",
      "b",
      "Frederic George",
      "f",
      "1863-1952",
      "4",
      "080"
    ],
    [
      "801",
      " 0",
      "a",
      "FR",
      "b",
      "BNF",
      "c",
      "19970701",
      "g",
      "AFNOR",
      "2",
      "intermrc"
    ]
  ]
}

Record methods

append()

Append an array of fields to the record. Fields are inserted in order, based on the tag of the first field. Returns the record itself, so chaining is possible. For example:

record
  .append(['952', '  ', 'a', 'MAIN', 'b', 'ANNEX', 'f', '12456', 'i', 'BOOK'],
          ['952', '  ', 'a', 'MAIN', 'b', 'MAIN', 'f', '45626', 'i', 'DVD'])
  .append(['801', '  ', 'a', 'MYLIB']);

as(format)

Return a string representation of the record, in a specific format given as method parameter:

• text -- A human readable version of the MARC record.
• iso2709 -- Legacy ISO2709 format.
• marcxml -- Standard MARCXML.
• json -- JSON stringified version of the native record object.
• mij -- MARC-in-JSON. Alternative serialization format, as described here: https://github.com/marc4j/marc4j/wiki/MARC-in-JSON-Description

Example:

let { Record } = require('marcjs');
let record = new Record();
record.append(['245', ' 1', 'a', 'MARC history:', 'b', 'to the end'], ['100', '  ', 'a', 'Fredo']);
console.log(record.as('text'));
console.log(record.as('mij'));
console.log(record.as('marcxml'));

clone()

Return a new record, clone of the record.

const clonedRecord = record.clone();

delete(match)

Delete all fiels which tag match match regular expression. Returns the record itself for chaining. For example:

record.delete(/9..|801/);

get(match)

Get fields with tag matching a regular expression. Returns an array of fiels in MARC-in-JSON format. If you want fields in MARC native format, just to a filter:

const fields = record.fields.filter((field) => field[0].match(/9..|801/));

match(match, cb)

record.match(/9..|801/, (field) => {} {

mij()

Return a MARC-in-JSON object representing the MARC record. Example:

{
  "leader": "00705cam  2200241   450 ",
  "fields": [
    {
      "001": "FRBNF465957890000009"
    },
    {
      "003": "http://catalogue.bnf.fr/ark:/12148/cb46595789r"
    },
    {
      "010": {
        "subfields": [
          {
            "b": "Br."
          }
        ],
        "ind1": " ",
        "ind2": " "
      }
    },
    {
      "100": {
        "subfields": [
          {
            "a": "20200814g2019    m  y0frey50      ba"
          }
        ],
        "ind1": " ",
        "ind2": " "
      }
    },
    {
      "200": {
        "subfields": [
          {
            "a": "Troie"
          },
          {
            "b": "Texte imprimé"
          },
          {
            "f": "David Gemmell"
          }
        ],
        "ind1": "1",
        "ind2": " "
      }
    },
    {
      "210": {
        "subfields": [
          {
            "a": "Paris"
          },
          {
            "c": "Bragelonne"
          },
          {
            "d": "DL 2016-"
          }
        ],
        "ind1": " ",
        "ind2": " "
      }
    },
    {
      "700": {
        "subfields": [
          {
            "3": "13548837"
          },
          {
            "o": "ISNI0000000121449147"
          },
          {
            "a": "Gemmell"
          },
          {
            "b": "David"
          },
          {
            "f": "1948-2006"
          },
          {
            "4": "070"
          }
        ],
        "ind1": " ",
        "ind2": "|"
      }
    }
  ]
}

Other classes

Marc object return other classes than Marc and Record classes. They can be invoqued directly.

• Iso2709 — Duplex stream reading/writing ISO2709 serialized records.
• Marcxml — Duplex stream reading/writing Marcxml serialized records.
• MiJ — Duplex stream reading/writing MARC-in-JSON serialized records.
• Text — Writable stream writing Text serialized records.
• Json — Writable stream writing Json serialized records. It's the marcjs native serialization format.

CLI marcjs

A command line script marcjs allows MARC record files manipulation from command line.

The module must be installed globaly: npm i marcjs -g.

Usage:

Usage: marc -p iso2709|marcxml|mij -f text|iso2709|marcxml|mij -o result file1 file2

Default parser is iso2709 and default formater is text. Parser/formater must be typed in lowercase.

Example:

# Same result: output a text version of bib1.mrc and bib2.mrc file
marcjs bib1.mrc bib2.mrc
marcjs -p iso2709 -f text bib1.mrc bib2.mrc
cat bib1.mrc bib2.txt | marcjs

# Output in MARC-in-JSON in bib1.mij file
marcjs -f mij -o bib1.mij bib1.mrc

Versions

• V1 : Until v1.2.3 (December 2020)
• V2 : From 2.0 (January 2021) — V2 changes the way the library is called.

• V3 : From 3.0.2 (March 2025) — Major interface change. Necessary to use properly nodejs Stream, and back pressure in order to handle very large stream of data.

License

Copyright (c) 2025 Frédéric Demians

Licensed under the MIT license.