gerhut / dnsz

Generic DNS zone file parser and stringifier

dnsz

Generic DNS zone file parser and stringifier

All current and future record types are supported as the module makes no effort to parse a record's content. It is highly configurable and has minimal dependencies.

Installation

$ npm i dnsz

Example

const dnsz = require("dnsz");

const data = dnsz.parse("example.com 60 IN A 1.2.3.4");
// => {records: [{name: "example.com", ttl: 60, class: "IN", type: "A", content: "1.2.3.4"}]}

dnsz.stringify(data);
// => ";; A Records\nexample.com.\t60\tIN\tA\t1.2.3.4\n"

API

dnsz.parse(str, [opts])

Parse a string of a DNS zone file and returns a data object.

• opts.replaceOrigin string: When specified, replaces any @ in name or content with it. Default: null.
• opts.crlf boolean: When true, emit \r\n instead of \n in header. Default: false.
• opts.defaultTTL number: Default TTL when absent and $TTL is not present. Default: 60.
• opts.dots boolean: Ensure trailing dots on FQDNs in content. Supports a limited amount of record types. Default: false.

dnsz.stringify(data, [opts])

Parse a data object and return a string with the zone file contents.

• opts.sections boolean: Whether to group records into sections. Default: true.
• opts.crlf boolean: When true, emit \r\n instead of \n for the resulting zone file. Default: false.
• opts.dots boolean: Ensure trailing dots on FQDNs in content. Supports a limited amount of record types. Default: false.

data object

• records: Array of record with these props:
  • name: The lowercase DNS name without a trailing dot, e.g. "example.com".
  • ttl: The TTL in seconds, e.g. 60.
  • class: The DNS class, e.g. "IN".
  • type: The record type, e.g. "A".
  • content: The record content, e.g. "2001:db8::1" or "example.com.".
  • comment: A comment, e.g. "a comment", null if absent.
• origin: The value of $ORIGIN in the zone file.
• ttl: The value of $TTL in the zone file.
• header: An optional header at the start of the file. Can be multiline. Does not include comment markers.

If data.origin is specified, the following things happen in the zone file output:

• A $ORIGIN variable is added.
• All occurences of data.origin within content are replaced with @.
• If data.origin matches the name of a record, name is replaced with @.

Example zone file

$ORIGIN originzone.com.

;; SOA Records
@   3600    IN  SOA originzone.com. root.originzone.com. 2031242781 7200 3600 86400 3600

;; A Records
@   60  IN  A   1.2.3.4 ; a comment
mx  60  IN  A   1.2.3.4 ; another comment

;; AAAA Records
@   120 IN  AAAA    2001:db8::1
mx  120 IN  AAAA    2001:db8::1

Example data object

{
  "origin": "originzone.com",
  "records": [
    {
      "name": "originzone.com",
      "ttl": 3600,
      "class": "IN",
      "type": "SOA",
      "content": "originzone.com. root.originzone.com. 2031242781 7200 3600 86400 3600",
      "comment": null
    },
    {
      "name": "originzone.com",
      "ttl": 60,
      "class": "IN",
      "type": "A",
      "content": "1.2.3.4",
      "comment": "a comment"
    },
    {
      "name": "mx",
      "ttl": 60,
      "class": "IN",
      "type": "A",
      "content": "1.2.3.4",
      "comment": "another comment"
    },
    {
      "name": "originzone.com",
      "ttl": 120,
      "class": "IN",
      "type": "AAAA",
      "content": "2001:db8::1",
      "comment": null
    },
    {
      "name": "mx",
      "ttl": 120,
      "class": "IN",
      "type": "AAAA",
      "content": "2001:db8::1",
      "comment": null
    }
  ]
}

License

© silverwind, distributed under BSD licence