refactor: cleanup isDNSLinkName mess

examples/gateway-car/api.go

@@ -139,6 +139,11 @@ func (api *blocksGateway) ResolvePath(ctx context.Context, p ifacepath.Path) (if
 	return ifacepath.NewResolvedPath(ipath, node, root, gopath.Join(rest...)), nil
 }
 
+func (api *blocksGateway) HasDNSLinkRecord(ctx context.Context, p ifacepath.Path) bool {
+	// Not implemented.
+	return false
+}
+
 func (api *blocksGateway) resolveNode(ctx context.Context, p ifacepath.Path) (format.Node, error) {
 	rp, err := api.ResolvePath(ctx, p)
 	if err != nil {

examples/go.mod

@@ -35,10 +35,7 @@ require (
 	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/golang/protobuf v1.5.2 // indirect
-	github.com/google/gopacket v1.1.19 // indirect
 	github.com/google/uuid v1.3.0 // indirect
-	github.com/hashicorp/errwrap v1.1.0 // indirect
-	github.com/hashicorp/go-multierror v1.1.1 // indirect
 	github.com/hashicorp/golang-lru v0.5.4 // indirect
 	github.com/ipfs/bbloom v0.0.4 // indirect
 	github.com/ipfs/go-bitfield v1.0.0 // indirect
@@ -55,20 +52,12 @@ require (
 	github.com/ipfs/go-log v1.0.5 // indirect
 	github.com/ipfs/go-log/v2 v2.5.1 // indirect
 	github.com/ipfs/go-metrics-interface v0.0.1 // indirect
-	github.com/ipfs/go-namesys v0.7.0 // indirect
 	github.com/ipfs/go-verifcid v0.0.2 // indirect
 	github.com/ipld/go-car v0.5.0 // indirect
 	github.com/jbenet/goprocess v0.1.4 // indirect
 	github.com/klauspost/cpuid/v2 v2.2.3 // indirect
 	github.com/libp2p/go-buffer-pool v0.1.0 // indirect
-	github.com/libp2p/go-cidranger v1.1.0 // indirect
 	github.com/libp2p/go-libp2p v0.23.4 // indirect
-	github.com/libp2p/go-libp2p-asn-util v0.2.0 // indirect
-	github.com/libp2p/go-libp2p-kad-dht v0.19.0 // indirect
-	github.com/libp2p/go-libp2p-kbucket v0.5.0 // indirect
-	github.com/libp2p/go-libp2p-record v0.2.0 // indirect
-	github.com/libp2p/go-msgio v0.2.0 // indirect
-	github.com/libp2p/go-netroute v0.2.0 // indirect
 	github.com/libp2p/go-openssl v0.1.0 // indirect
 	github.com/mattn/go-isatty v0.0.17 // indirect
 	github.com/mattn/go-pointer v0.0.1 // indirect
@@ -79,7 +68,6 @@ require (
 	github.com/multiformats/go-base32 v0.1.0 // indirect
 	github.com/multiformats/go-base36 v0.2.0 // indirect
 	github.com/multiformats/go-multiaddr v0.8.0 // indirect
-	github.com/multiformats/go-multiaddr-dns v0.3.1 // indirect
 	github.com/multiformats/go-multibase v0.1.1 // indirect
 	github.com/multiformats/go-multicodec v0.7.0 // indirect
 	github.com/multiformats/go-multihash v0.2.1 // indirect
@@ -96,11 +84,8 @@ require (
 	github.com/spacemonkeygo/spacelog v0.0.0-20180420211403-2296661a0572 // indirect
 	github.com/spaolacci/murmur3 v1.1.0 // indirect
 	github.com/ucarion/urlpath v0.0.0-20200424170820-7ccc79b76bbb // indirect
-	github.com/whyrusleeping/base32 v0.0.0-20170828182744-c30ac30633cc // indirect
 	github.com/whyrusleeping/cbor v0.0.0-20171005072247-63513f603b11 // indirect
 	github.com/whyrusleeping/cbor-gen v0.0.0-20230126041949-52956bd4c9aa // indirect
-	github.com/whyrusleeping/go-keyspace v0.0.0-20160322163242-5b898ac5add1 // indirect
-	go.opencensus.io v0.23.0 // indirect
 	go.opentelemetry.io/otel v1.12.0 // indirect
 	go.opentelemetry.io/otel/trace v1.12.0 // indirect
 	go.uber.org/atomic v1.10.0 // indirect

gateway/gateway.go

@@ -39,6 +39,11 @@ type API interface {
 	// exist due to a missing link, it should return an error of type:
 	// https://pkg.go.dev/github.com/ipfs/go-path@v0.3.0/resolver#ErrNoLink
 	ResolvePath(context.Context, path.Path) (path.Resolved, error)
+
+	// HasDNSLinkRecord returns if the provided path has a DNSLink TXT record.
+	// It does not perform any validation, only checks for the existence of
+	// a DNSLink TXT record.
+	HasDNSLinkRecord(context.Context, path.Path) bool
 }
 
 // A helper function to clean up a set of headers:

gateway/hostname.go

@@ -10,7 +10,6 @@ import (
 	"strings"
 
 	cid "github.com/ipfs/go-cid"
-	"github.com/ipfs/go-namesys"
 	"github.com/ipfs/interface-go-ipfs-core/path"
 	"github.com/libp2p/go-libp2p/core/peer"
 	dns "github.com/miekg/dns"
@@ -113,7 +112,7 @@ func WithHostname(next http.Handler, api API, publicGateways map[string]*Specifi
 			// Not a whitelisted path
 
 			// Try DNSLink, if it was not explicitly disabled for the hostname
-			if !gw.NoDNSLink && isDNSLinkName(r.Context(), api, host) {
+			if !gw.NoDNSLink && hasDNSLinkRecord(r.Context(), api, host) {
 				// rewrite path and handle as DNSLink
 				r.URL.Path = "/ipns/" + stripPort(host) + r.URL.Path
 				next.ServeHTTP(w, withHostnameContext(r, host))
@@ -184,7 +183,6 @@ func WithHostname(next http.Handler, api API, publicGateways map[string]*Specifi
 					}
 				}
 			} else { // rootID is not a CID..
-
 				// Check if rootID is a single DNS label with an inlined
 				// DNSLink FQDN a single DNS label. We support this so
 				// loading DNSLink names over TLS "just works" on public
@@ -200,10 +198,10 @@ func WithHostname(next http.Handler, api API, publicGateways map[string]*Specifi
 				// https://my-v--long-example-com.ipns.dweb.link
 				if ns == "ipns" && !strings.Contains(rootID, ".") {
 					// if there is no TXT recordfor rootID
-					if !isDNSLinkName(r.Context(), api, rootID) {
+					if !hasDNSLinkRecord(r.Context(), api, rootID) {
 						// my-v--long-example-com → my.v-long.example.com
 						dnslinkFQDN := toDNSLinkFQDN(rootID)
-						if isDNSLinkName(r.Context(), api, dnslinkFQDN) {
+						if hasDNSLinkRecord(r.Context(), api, dnslinkFQDN) {
 							// update path prefix to use real FQDN with DNSLink
 							pathPrefix = "/ipns/" + dnslinkFQDN
 						}
@@ -218,13 +216,14 @@ func WithHostname(next http.Handler, api API, publicGateways map[string]*Specifi
 			next.ServeHTTP(w, withHostnameContext(r, gwHostname))
 			return
 		}
+
 		// We don't have a known gateway. Fallback on DNSLink lookup
 
 		// Wildcard HTTP Host check:
 		// 1. is wildcard DNSLink enabled (Gateway.NoDNSLink=false)?
 		// 2. does Host header include a fully qualified domain name (FQDN)?
 		// 3. does DNSLink record exist in DNS?
-		if !noDNSLink && isDNSLinkName(r.Context(), api, host) {
+		if !noDNSLink && hasDNSLinkRecord(r.Context(), api, host) {
 			// rewrite path and handle as DNSLink
 			r.URL.Path = "/ipns/" + stripPort(host) + r.URL.Path
 			ctx := context.WithValue(r.Context(), DNSLinkHostnameKey, host)
@@ -262,18 +261,16 @@ func isDomainNameAndNotPeerID(hostname string) bool {
 	return ok
 }
 
-// isDNSLinkName returns bool if a valid DNS TXT record exist for provided host
-func isDNSLinkName(ctx context.Context, api API, host string) bool {
+// hasDNSLinkRecord returns if a DNS TXT record exists for the provided host.
+func hasDNSLinkRecord(ctx context.Context, api API, host string) bool {
 	dnslinkName := stripPort(host)
 
 	if !isDomainNameAndNotPeerID(dnslinkName) {
 		return false
 	}
 
 	name := "/ipns/" + dnslinkName
-	_, err := api.ResolvePath(ctx, path.New(name))
-	// check if DNSLink exists
-	return err == nil || err == namesys.ErrResolveRecursion
+	return api.HasDNSLinkRecord(ctx, path.New(name))
 }
 
 func isSubdomainNamespace(ns string) bool {
@@ -456,7 +453,7 @@ func toSubdomainURL(hostname, path string, r *http.Request, inlineDNSLink bool,
 		// represented as a single DNS label:
 		// https://my-v--long-example-com.ipns.dweb.link
 		if (inlineDNSLink || isHTTPS) && ns == "ipns" && strings.Contains(rootID, ".") {
-			if isDNSLinkName(r.Context(), api, rootID) {
+			if hasDNSLinkRecord(r.Context(), api, rootID) {
 				// my.v-long.example.com → my-v--long-example-com
 				dnsLabel, err := toDNSLinkDNSLabel(rootID)
 				if err != nil {

go.mod

@@ -27,7 +27,6 @@ require (
 	github.com/ipfs/go-log v1.0.5
 	github.com/ipfs/go-log/v2 v2.5.1
 	github.com/ipfs/go-metrics-interface v0.0.1
-	github.com/ipfs/go-namesys v0.7.0
 	github.com/ipfs/go-path v0.3.0
 	github.com/ipfs/go-peertaskqueue v0.8.0
 	github.com/ipfs/interface-go-ipfs-core v0.10.0
@@ -65,8 +64,6 @@ require (
 	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/google/gopacket v1.1.19 // indirect
-	github.com/hashicorp/errwrap v1.1.0 // indirect
-	github.com/hashicorp/go-multierror v1.1.1 // indirect
 	github.com/hashicorp/golang-lru v0.5.4 // indirect
 	github.com/huin/goupnp v1.0.3 // indirect
 	github.com/ipfs/bbloom v0.0.4 // indirect
@@ -85,8 +82,6 @@ require (
 	github.com/koron/go-ssdp v0.0.3 // indirect
 	github.com/libp2p/go-cidranger v1.1.0 // indirect
 	github.com/libp2p/go-libp2p-asn-util v0.2.0 // indirect
-	github.com/libp2p/go-libp2p-kad-dht v0.19.0 // indirect
-	github.com/libp2p/go-libp2p-kbucket v0.5.0 // indirect
 	github.com/libp2p/go-nat v0.1.0 // indirect
 	github.com/libp2p/go-netroute v0.2.0 // indirect
 	github.com/libp2p/go-openssl v0.1.0 // indirect
@@ -111,9 +106,7 @@ require (
 	github.com/spaolacci/murmur3 v1.1.0 // indirect
 	github.com/stretchr/objx v0.5.0 // indirect
 	github.com/ucarion/urlpath v0.0.0-20200424170820-7ccc79b76bbb // indirect
-	github.com/whyrusleeping/base32 v0.0.0-20170828182744-c30ac30633cc // indirect
 	github.com/whyrusleeping/cbor-gen v0.0.0-20221220214510-0333c149dec0 // indirect
-	github.com/whyrusleeping/go-keyspace v0.0.0-20160322163242-5b898ac5add1 // indirect
 	go.uber.org/atomic v1.10.0 // indirect
 	golang.org/x/crypto v0.0.0-20220525230936-793ad666bf5e // indirect
 	golang.org/x/exp v0.0.0-20220916125017-b168a2c6b86b // indirect

go.sum

@@ -309,14 +309,10 @@ github.com/gxed/hashland/murmur3 v0.0.1/go.mod h1:KjXop02n4/ckmZSnY2+HKcLud/tcmv
 github.com/hashicorp/consul/api v1.3.0/go.mod h1:MmDNSzIMUjNpY/mQ398R4bk2FnqQLoPndWW5VkKPlCE=
 github.com/hashicorp/consul/sdk v0.3.0/go.mod h1:VKf9jXwCTEY1QZP2MOLRhb5i/I/ssyNV1vwHyQBF0x8=
 github.com/hashicorp/errwrap v1.0.0/go.mod h1:YH+1FKiLXxHSkmPseP+kNlulaMuP3n2brvKWEqk/Jc4=
-github.com/hashicorp/errwrap v1.1.0 h1:OxrOeh75EUXMY8TBjag2fzXGZ40LB6IKw45YeGUDY2I=
-github.com/hashicorp/errwrap v1.1.0/go.mod h1:YH+1FKiLXxHSkmPseP+kNlulaMuP3n2brvKWEqk/Jc4=
 github.com/hashicorp/go-cleanhttp v0.5.1/go.mod h1:JpRdi6/HCYpAwUzNwuwqhbovhLtngrth3wmdIIUrZ80=
 github.com/hashicorp/go-immutable-radix v1.0.0/go.mod h1:0y9vanUI8NX6FsYoO3zeMjhV/C5i9g4Q3DwcSNZ4P60=
 github.com/hashicorp/go-msgpack v0.5.3/go.mod h1:ahLV/dePpqEmjfWmKiqvPkv/twdG7iPBM1vqhUKIvfM=
 github.com/hashicorp/go-multierror v1.0.0/go.mod h1:dHtQlpGsu+cZNNAkkCN/P3hoUDHhCYQXV3UM06sGGrk=
-github.com/hashicorp/go-multierror v1.1.1 h1:H5DkEtf6CXdFp0N0Em5UCwQpXMWke8IA0+lD48awMYo=
-github.com/hashicorp/go-multierror v1.1.1/go.mod h1:iw975J/qwKPdAO1clOe2L8331t/9/fmwbPZ6JB6eMoM=
 github.com/hashicorp/go-rootcerts v1.0.0/go.mod h1:K6zTfqpRlCUIjkwsN4Z+hiSfzSTQa6eBIzfwKfwNnHU=
 github.com/hashicorp/go-sockaddr v1.0.0/go.mod h1:7Xibr9yA9JjQq1JpNB2Vw7kxv8xerXegt+ozgdvDeDU=
 github.com/hashicorp/go-syslog v1.0.0/go.mod h1:qPfqrKkXGihmCqbJM2mZgkZGvKG1dFdvsLplgctolz4=
@@ -464,8 +460,6 @@ github.com/ipfs/go-merkledag v0.9.0 h1:DFC8qZ96Dz1hMT7dtIpcY524eFFDiEWAF8hNJHWW2
 github.com/ipfs/go-merkledag v0.9.0/go.mod h1:bPHqkHt5OZ0p1n3iqPeDiw2jIBkjAytRjS3WSBwjq90=
 github.com/ipfs/go-metrics-interface v0.0.1 h1:j+cpbjYvu4R8zbleSs36gvB7jR+wsL2fGD6n0jO4kdg=
 github.com/ipfs/go-metrics-interface v0.0.1/go.mod h1:6s6euYU4zowdslK0GKHmqaIZ3j/b/tL7HTWtJ4VPgWY=
-github.com/ipfs/go-namesys v0.7.0 h1:xqosk71GIVRkFDtF2UNRcXn4LdNeo7tzuy8feHD6NbU=
-github.com/ipfs/go-namesys v0.7.0/go.mod h1:KYSZBVZG3VJC34EfqqJPG7T48aWgxseoMPAPA5gLyyQ=
 github.com/ipfs/go-path v0.3.0 h1:tkjga3MtpXyM5v+3EbRvOHEoo+frwi4oumw5K+KYWyA=
 github.com/ipfs/go-path v0.3.0/go.mod h1:NOScsVgxfC/eIw4nz6OiGwK42PjaSJ4Y/ZFPn1Xe07I=
 github.com/ipfs/go-peertaskqueue v0.1.0/go.mod h1:Jmk3IyCcfl1W3jTW3YpghSwSEC6IJ3Vzz/jUmWw8Z0U=
@@ -615,10 +609,6 @@ github.com/libp2p/go-libp2p-discovery v0.1.0/go.mod h1:4F/x+aldVHjHDHuX85x1zWoFT
 github.com/libp2p/go-libp2p-discovery v0.2.0/go.mod h1:s4VGaxYMbw4+4+tsoQTqh7wfxg97AEdo4GYBt6BadWg=
 github.com/libp2p/go-libp2p-discovery v0.3.0/go.mod h1:o03drFnz9BVAZdzC/QUQ+NeQOu38Fu7LJGEOK2gQltw=
 github.com/libp2p/go-libp2p-discovery v0.5.0/go.mod h1:+srtPIU9gDaBNu//UHvcdliKBIcr4SfDcm0/PfPJLug=
-github.com/libp2p/go-libp2p-kad-dht v0.19.0 h1:2HuiInHZTm9ZvQajaqdaPLHr0PCKKigWiflakimttE0=
-github.com/libp2p/go-libp2p-kad-dht v0.19.0/go.mod h1:qPIXdiZsLczhV4/+4EO1jE8ae0YCW4ZOogc4WVIyTEU=
-github.com/libp2p/go-libp2p-kbucket v0.5.0 h1:g/7tVm8ACHDxH29BGrpsQlnNeu+6OF1A9bno/4/U1oA=
-github.com/libp2p/go-libp2p-kbucket v0.5.0/go.mod h1:zGzGCpQd78b5BNTDGHNDLaTt9aDK/A02xeZp9QeFC4U=
 github.com/libp2p/go-libp2p-loggables v0.1.0/go.mod h1:EyumB2Y6PrYjr55Q3/tiJ/o3xoDasoRYM7nOzEpoa90=
 github.com/libp2p/go-libp2p-mplex v0.2.0/go.mod h1:Ejl9IyjvXJ0T9iqUTE1jpYATQ9NM3g+OtR+EMMODbKo=
 github.com/libp2p/go-libp2p-mplex v0.2.1/go.mod h1:SC99Rxs8Vuzrf/6WhmH41kNn13TiYdAWNYHrwImKLnE=
@@ -1078,13 +1068,10 @@ github.com/warpfork/go-wish v0.0.0-20180510122957-5ad1f5abf436/go.mod h1:x6AKhvS
 github.com/warpfork/go-wish v0.0.0-20190328234359-8b3e70f8e830/go.mod h1:x6AKhvSSexNrVSrViXSHUEbICjmGXhtgABaHIySUSGw=
 github.com/warpfork/go-wish v0.0.0-20200122115046-b9ea61034e4a h1:G++j5e0OC488te356JvdhaM8YS6nMsjLAYF7JxCv07w=
 github.com/warpfork/go-wish v0.0.0-20200122115046-b9ea61034e4a/go.mod h1:x6AKhvSSexNrVSrViXSHUEbICjmGXhtgABaHIySUSGw=
-github.com/whyrusleeping/base32 v0.0.0-20170828182744-c30ac30633cc h1:BCPnHtcboadS0DvysUuJXZ4lWVv5Bh5i7+tbIyi+ck4=
-github.com/whyrusleeping/base32 v0.0.0-20170828182744-c30ac30633cc/go.mod h1:r45hJU7yEoA81k6MWNhpMj/kms0n14dkzkxYHoB96UM=
 github.com/whyrusleeping/cbor-gen v0.0.0-20200123233031-1cdf64d27158/go.mod h1:Xj/M2wWU+QdTdRbu/L/1dIZY8/Wb2K9pAhtroQuxJJI=
 github.com/whyrusleeping/cbor-gen v0.0.0-20221220214510-0333c149dec0 h1:obKzQ1ey5AJg5NKjgtTo/CKwLImVP4ETLRcsmzFJ4Qw=
 github.com/whyrusleeping/cbor-gen v0.0.0-20221220214510-0333c149dec0/go.mod h1:fgkXqYy7bV2cFeIEOkVTZS/WjXARfBqSH6Q2qHL33hQ=
 github.com/whyrusleeping/chunker v0.0.0-20181014151217-fe64bd25879f/go.mod h1:p9UJB6dDgdPgMJZs7UjUOdulKyRr9fqkS+6JKAInPy8=
-github.com/whyrusleeping/go-keyspace v0.0.0-20160322163242-5b898ac5add1 h1:EKhdznlJHPMoKr0XTrX+IlJs1LH3lyx2nfr1dOlZ79k=
 github.com/whyrusleeping/go-keyspace v0.0.0-20160322163242-5b898ac5add1/go.mod h1:8UvriyWtv5Q5EOgjHaSseUEdkQfvwFv1I/In/O2M9gc=
 github.com/whyrusleeping/go-logging v0.0.0-20170515211332-0457bb6b88fc/go.mod h1:bopw91TMyo8J3tvftk8xmU2kPmlrt4nScJQZU2hE5EM=
 github.com/whyrusleeping/go-logging v0.0.1/go.mod h1:lDPYj54zutzG1XYfHAhcc7oNXEburHQBn+Iqd4yS4vE=