ldif

node-ldif

Nodejs LDIF (LDAP Data Interchange Format) parser based on RFC2849

Unless you are an LDAP aficionado you may not know about the LDIF format. I was surprised to learn that no LDIF parsing library existed for node.

So I wrote one, with peg.js. It aims to be RFC-compliant.
Now I'll never have to use that cursed perl script again!

Design Goals

• 100% RFC-compliance; should comprehend any valid LDIF file
• Parsed records stored internally intact
• Methods are provided to extract record data in various formats
• Outputs exactly compatilble LDIF for any parsed record or file
• Automatic decoding and outputting of base64 data
• No external library dependencies; pure Node Javascript

Usage

Installation

Install easily with npm!

npm install ldif

Parsing

Parsing strings

var ldif = require('ldif'),
    file = './rfc/example1.ldif',
    input = require('fs').readFileSync(file,'utf8');

console.log(ldif.parse(input));

After reading the file, it's parsed as a string.
There's also a shorthand to read in a file (synchronously, as above):

File parsing shorthand

var ldif = require('ldif');
console.log(ldif.parseFile('./rfc/example1.ldif'));

Parsing an LDIF file returns an object format for an entire LDIF file.
In this case, example1.ldif specifies contents of two LDAP records.

Shifting records from parsed file

var ldif = require('ldif');
    file = ldif.parseFile('./rfc/example1.ldif');

var record = file.shift();

Records are stored in an internal format, using classic Javascript objects. The type or value specified in a type property for all objects, but they can also be tested for specific constructor types:

var ldif = require('ldif');
    file = ldif.parseFile('./rfc/example1.ldif');

(file instanceof ldif.Container)        === true
(file.shift() instanceof ldif.Record)   === true

Converting

File data to plain object

var ldif = require('ldif');
    file = ldif.parseFile('./rfc/example1.ldif'),
    output_options = {};

console.log(file.toObject(output_options));

Returns the following result:

{ type: 'content',
  version: 1,
  entries: 
   [ { dn: 'cn=Barbara Jensen, ou=Product Development, dc=airius, dc=com',
       attributes: [Object] },
     { dn: 'cn=Bjorn Jensen, ou=Accounting, dc=airius, dc=com',
       attributes: [Object] } ] }

Again, this is for the entire file. It's more common you'd want to operate on individual records:

Record to plain object

var ldif = require('ldif');
    file = ldif.parseFile('./rfc/example1.ldif'),
    output_options = {};

var record = file.shift();
console.log(record.toObject(output_options));

Output of the above code is this:

{ dn: 'cn=Barbara Jensen, ou=Product Development, dc=airius, dc=com',
  attributes: 
   { objectclass: [ 'top', 'person', 'organizationalPerson' ],
     cn: [ 'Barbara Jensen', 'Barbara J Jensen', 'Babs Jensen' ],
     sn: 'Jensen',
     uid: 'bjensen',
     telephonenumber: '[phone]',
     description: 'A big sailing fan.' } }

Notice the default behavior outputs attribute key/value pairs that have values of either an array or single string. Since an attribute can be single- or multi-valued, this format makes sense in most cases.

There is a way to pass an options object to this method and alter the benavior. For now that is left as an exercise for the reader. If you want a hint, look in the source for Record.defaults and how those settings interact.

Important note: The toObject() methods are not currently implemented for change format files or entries.

Outputting LDIF for parsed files

All parsed data can be written back to LDIF format using a toLDIF() method (on files or entries).

var ldif = require('ldif');
    file = ldif.parseFile('./rfc/example1.ldif');

// the whole file
console.log(file.toLDIF());

// or just a single record
console.log(file.shift().toLDIF());

TODO

• toObject() methods for change schema and entries
• Streaming read interface (coming soon--probably as a seperate package)
• Construct and alter objects through code
• More complete documentation
• Test suite