urn 

Parse and format URN strings in either the RFC 2141 or RFC 8141 standards. A non-standard AWS "arn" parser is also included.

No dependencies. Has tests. Ships both CJS and ESM. PRs welcome.

Two interfaces are provided by the lib:
- Classes modeled after the built-in URL class e.g. new Rfc8141Urn('urn:ietf:rfc:7230')
- Functional utils for parsing and formatting e.g. parseRfc8141Urn('ietf:rfc:7230') and formatRfc8141Urn(parsedObj). Note that these expect protocol to be stripped, which can be done using parseProtocol and formatProtocol, if needed

Getting started

Run npm i urn-lib. More complete examples are available in "examples/" and should get you started:
``ts
import { Rfc8141Urn } from 'urn-lib';
// Functions parseRfc8141Urn and formatRfc8141Urn are available
// as well, but note that they expect input without a protocol
// i.e. "example:value" instead of "urn:example:value".
// See examples/rfc/rfc8141_utils.ts for example

const urn = new Rfc8141Urn('urn:example:value');
console.log('Parsed', { // Alternatively, you could to urn.toJSON()
ref: urn.ref,
protocol: urn.protocol,
value: urn.value,
nid: urn.nid,
nss: urn.nss,
// Like with URL, these values include the prefix
// e.g. rComponent would start with "?+" if it was
// included in the input, or an empty string if not
rComponent: urn.rComponent,
qComponent: urn.qComponent,
fComponent: urn.fComponent,
});
// Parsed {
// ref: 'urn:example:value',
// protocol: 'urn:',
// value: 'example:value',
// nid: 'example',
// nss: 'value',
// rComponent: '',
// qComponent: '',
// fComponent: ''
// }

console.log('Formatted', urn.toString()); // Formatted urn:example:value

urn.nss = 'world';
console.log('Hello', urn.toString()); // Formatted urn:example:world
`

Legacy v2 and earlier

As of v3, the lib as been completely rewritten, however, legacy code still exists as-is and is available.

This will be removed in a future v4, but still available via export defined in package.json i.e. import ... from 'urn-lib/legacy'`.

The legacy code readme is still available.