fix: align implicit default ttl with specs (1h→5m) (#336)

This PR is changing implicit default TTL of IPNS Record produced by this library from 1h to 5m.

Same rationale as ipfs/kubo#10718 and ipfs/helia#749. This library has its own default TTL, which is separate from one we already updated ipfs/helia#749. Making this change so we have the same default everywhere.

Historical notes
- Before April 2024 the IPNS Record TTL was not set (0) in this library
- Since #308 the `1h` default produced by this library started causing stale cache issues that end users often report as "ipns is slow (to update/propagate)".
- We've changed default recommendation to 5m in ipfs/specs#492

Author: lidel

src/index.ts

@@ -11,7 +11,7 @@ import type { CID } from 'multiformats/cid'
 import type { MultihashDigest } from 'multiformats/hashes/interface'
 
 const log = logger('ipns')
-const DEFAULT_TTL_NS = 60 * 60 * 1e+9 // 1 Hour or 3600 Seconds
+const DEFAULT_TTL_NS = 5 * 60 * 1e+9 // 5 Minutes or 300 Seconds, as suggested by https://specs.ipfs.tech/ipns/ipns-record/#ttl-uint64
 
 export const namespace = '/ipns/'
 export const namespaceLength = namespace.length

test/index.spec.ts

@@ -31,7 +31,7 @@ describe('ipns', function () {
 
   it('should create an ipns record (V1+V2) correctly', async () => {
     const sequence = 0
-    const ttl = BigInt(60 * 60 * 1e+9)
+    const ttl = BigInt(5 * 60 * 1e+9)
     const validity = 1000000
 
     const record = await createIPNSRecord(privateKey, contentPath, sequence, validity)
@@ -67,7 +67,7 @@ describe('ipns', function () {
 
   it('should create an ipns record (V2) correctly', async () => {
     const sequence = 0
-    const ttl = BigInt(60 * 60 * 1e+9)
+    const ttl = BigInt(5 * 60 * 1e+9)
     const validity = 1000000
 
     const record = await createIPNSRecord(privateKey, contentPath, sequence, validity, { v1Compatible: false })