refactor: config.DefaultIpnsMaxCacheTTL

config/ipns.go

@@ -1,5 +1,14 @@
 package config
 
+import (
+	"math"
+	"time"
+)
+
+const (
+	DefaultIpnsMaxCacheTTL = time.Duration(math.MaxInt64)
+)
+
 type Ipns struct {
 	RepublishPeriod string
 	RecordLifetime  string

core/coreapi/coreapi.go

@@ -14,7 +14,6 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"time"
 
 	bserv "github.com/ipfs/boxo/blockservice"
 	blockstore "github.com/ipfs/boxo/blockstore"
@@ -27,6 +26,7 @@ import (
 	provider "github.com/ipfs/boxo/provider"
 	offlineroute "github.com/ipfs/boxo/routing/offline"
 	ipld "github.com/ipfs/go-ipld-format"
+	"github.com/ipfs/kubo/config"
 	coreiface "github.com/ipfs/kubo/core/coreiface"
 	"github.com/ipfs/kubo/core/coreiface/options"
 	pubsub "github.com/libp2p/go-libp2p-pubsub"
@@ -230,11 +230,7 @@ func (api *CoreAPI) WithOptions(opts ...options.ApiOption) (coreiface.CoreAPI, e
 			namesys.WithDatastore(subAPI.repo.Datastore()),
 			namesys.WithDNSResolver(subAPI.dnsResolver),
 			namesys.WithCache(cs),
-		}
-
-		if !cfg.Ipns.MaxCacheTTL.IsDefault() {
-			// Default value won't be used since we check for it. There is no default.
-			nsOptions = append(nsOptions, namesys.WithMaxCacheTTL(cfg.Ipns.MaxCacheTTL.WithDefault(time.Second)))
+			namesys.WithMaxCacheTTL(cfg.Ipns.MaxCacheTTL.WithDefault(config.DefaultIpnsMaxCacheTTL)),
 		}
 
 		subAPI.routing = offlineroute.NewOfflineRouter(subAPI.repo.Datastore(), subAPI.recordValidator)

core/corehttp/gateway.go

@@ -139,11 +139,7 @@ func newGatewayBackend(n *core.IpfsNode) (gateway.IPFSBackend, error) {
 			namesys.WithDatastore(n.Repo.Datastore()),
 			namesys.WithDNSResolver(n.DNSResolver),
 			namesys.WithCache(cs),
-		}
-
-		if !cfg.Ipns.MaxCacheTTL.IsDefault() {
-			// Default value won't be used since we check for it. There is no default.
-			nsOptions = append(nsOptions, namesys.WithMaxCacheTTL(cfg.Ipns.MaxCacheTTL.WithDefault(time.Second)))
+			namesys.WithMaxCacheTTL(cfg.Ipns.MaxCacheTTL.WithDefault(config.DefaultIpnsMaxCacheTTL)),
 		}
 
 		vsRouting = offlineroute.NewOfflineRouter(n.Repo.Datastore(), n.RecordValidator)

core/node/groups.go

@@ -273,7 +273,7 @@ func Online(bcfg *BuildCfg, cfg *config.Config, userResourceOverrides rcmgr.Part
 		fx.Provide(BitswapOptions(cfg, shouldBitswapProvide)),
 		fx.Provide(OnlineExchange()),
 		fx.Provide(DNSResolver),
-		fx.Provide(Namesys(ipnsCacheSize, cfg.Ipns.MaxCacheTTL.WithDefault(0))),
+		fx.Provide(Namesys(ipnsCacheSize, cfg.Ipns.MaxCacheTTL.WithDefault(config.DefaultIpnsMaxCacheTTL))),
 		fx.Provide(Peering),
 		PeerWith(cfg.Peering.Peers...),
 

core/node/ipns.go

@@ -33,14 +33,12 @@ func Namesys(cacheSize int, cacheMaxTTL time.Duration) func(rt irouting.ProvideM
 		opts := []namesys.Option{
 			namesys.WithDatastore(repo.Datastore()),
 			namesys.WithDNSResolver(rslv),
+			namesys.WithMaxCacheTTL(cacheMaxTTL),
 		}
 
 		if cacheSize > 0 {
 			opts = append(opts, namesys.WithCache(cacheSize))
 		}
-		if cacheMaxTTL > 0 {
-			opts = append(opts, namesys.WithMaxCacheTTL(cacheMaxTTL))
-		}
 
 		return namesys.NewNameSystem(rt, opts...)
 	}

docs/config.md

@@ -1141,16 +1141,30 @@ Type: `integer` (non-negative, 0 means the default)
 
 ### `Ipns.MaxCacheTTL`
 
-Maximum duration for which entries are valid in the name system cache.
+Maximum duration for which entries are valid in the name system cache. Applied
+to everything under `/ipns/` namespace, allows you to cap
+the [Time-To-Live (TTL)](https://specs.ipfs.tech/ipns/ipns-record/#ttl-uint64) of
+[IPNS Records](https://specs.ipfs.tech/ipns/ipns-record/)
+AND also DNSLink TXT records (when DoH-specific [`DNS.MaxCacheTTL`](https://github.com/ipfs/kubo/blob/master/docs/config.md#dnsmaxcachettl)
+is not set to a lower value).
 
-This allows you to cap the Time-To-Live suggested by [IPNS entries](https://specs.ipfs.tech/ipns/ipns-record/#ttl-uint64).
-If present, the upper bound is applied to the resolved IPNS entries.
+When `Ipns.MaxCacheTTL` is set, it defines the upper bound limit of how long a
+[IPNS Name](https://specs.ipfs.tech/ipns/ipns-record/#ipns-name) lookup result
+will be cached and read from cache before checking for updates.
 
 **Examples:**
-* `"5m"` DNS entries are kept for 5 minutes or less.
-* `"0s"` DNS entries expire as soon as they are retrieved.
+* `"1m"` IPNS results are cached 1m or less (good compromise for system where
+  faster updates are desired).
+* `"0s"` IPNS caching is effectively turned off (useful for testing, bad for production use)
+  - **Note:** setting this to `0` will turn off TTL-based caching entirely.
+    This is discouraged in production environments. It will make IPNS websites
+    artificially slow because IPNS resolution results will expire as soon as
+    they are retrieved, forcing expensive IPNS lookup to happen on every
+    request. If you want near-real-time IPNS, set it to a low, but still
+    sensible value, such as `1m`.
+
+Default: No upper bound, [TTL from IPNS Record](https://specs.ipfs.tech/ipns/ipns-record/#ttl-uint64)  (see `ipns name publish --help`) is always respected.
 
-Default: Respect IPNS entry TTL
 
 Type: `optionalDuration`
 
@@ -2333,7 +2347,7 @@ If present, the upper bound is applied to DoH resolvers in [`DNS.Resolvers`](#dn
 Note: this does NOT work with Go's default DNS resolver. To make this a global setting, add a `.` entry to `DNS.Resolvers` first.
 
 **Examples:**
-* `"5m"` DNS entries are kept for 5 minutes or less.
+* `"1m"` DNS entries are kept for 1 minute or less.
 * `"0s"` DNS entries expire as soon as they are retrieved.
 
 Default: Respect DNS Response TTL