gateway: initial hostname-based routing

Replace IPNSHostname based routing with general-purpose hostname-based routing
that also supports handling requests to "known gateways".

TODO: I'll break KnownGateways out into a config option in a later commit.

License: MIT
Signed-off-by: Steven Allen <steven@stebalien.com>

cmd/ipfs/daemon.go

@@ -588,7 +588,7 @@ func serveHTTPGateway(req *cmds.Request, cctx *oldcmds.Context) (<-chan error, e
 	var opts = []corehttp.ServeOption{
 		corehttp.ProxyOption(), // Proxies all CONNECT requests to self. Always put this first.
 		corehttp.MetricsCollectionOption("gateway"),
-		corehttp.IPNSHostnameOption(),
+		corehttp.HostnameOption(),
 		corehttp.GatewayOption(writable, "/ipfs", "/ipns"),
 		corehttp.VersionOption(),
 		corehttp.CheckVersionOption(),

core/corehttp/gateway_handler.go

@@ -34,6 +34,28 @@ const (
 	ipnsPathPrefix = "/ipns/"
 )
 
+type GatewaySpec struct {
+	// PathPrefixes list the set of path prefixes that should be handled by
+	// the gateway logic.
+	PathPrefixes []string
+
+	// SupportsSubdomains indicates whether or not this gateway supports
+	// requests of the form http://CID.ipfs.GATEWAY/...
+	SupportsSubdomains bool
+}
+
+var DefaultGatewaySpec = GatewaySpec{
+	PathPrefixes:       []string{ipfsPathPrefix, ipnsPathPrefix, "/api/"},
+	SupportsSubdomains: true,
+}
+
+// TODO(steb): Configurable
+var KnownGateways = map[string]GatewaySpec{
+	"ipfs.io":         DefaultGatewaySpec,
+	"gateway.ipfs.io": DefaultGatewaySpec,
+	"localhost:8080":  DefaultGatewaySpec,
+}
+
 // gatewayHandler is a HTTP handler that serves IPFS objects (accessible by default at /ipfs/<path>)
 // (it serves requests like GET /ipfs/QmVRzPKPzNtSrEzBFm2UZfxmPAgnaLke4DMcerbsGGSaFe/link)
 type gatewayHandler struct {
@@ -133,7 +155,7 @@ func (i *gatewayHandler) getOrHeadHandler(ctx context.Context, w http.ResponseWr
 		}
 	}
 
-	// IPNSHostnameOption might have constructed an IPNS path using the Host header.
+	// HostnameOption might have constructed an IPNS/IPFS path using the Host header.
 	// In this case, we need the original path for constructing redirects
 	// and links that match the requested URL.
 	// For example, http://example.net would become /ipns/example.net, and

core/corehttp/gateway_test.go

@@ -137,7 +137,7 @@ func newTestServerAndNode(t *testing.T, ns mockNamesys) (*httptest.Server, iface
 
 	dh.Handler, err = makeHandler(n,
 		ts.Listener,
-		IPNSHostnameOption(),
+		HostnameOption(),
 		GatewayOption(false, "/ipfs", "/ipns"),
 		VersionOption(),
 	)

core/corehttp/ipns_hostname.go → core/corehttp/hostname.go

@@ -13,26 +13,66 @@ import (
 	isd "github.com/jbenet/go-is-domain"
 )
 
-// IPNSHostnameOption rewrites an incoming request if its Host: header contains
-// an IPNS name.
-// The rewritten request points at the resolved name on the gateway handler.
-func IPNSHostnameOption() ServeOption {
+// HostnameOption rewrites an incoming request based on the Host header.
+func HostnameOption() ServeOption {
 	return func(n *core.IpfsNode, _ net.Listener, mux *http.ServeMux) (*http.ServeMux, error) {
 		childMux := http.NewServeMux()
 		mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
 			ctx, cancel := context.WithCancel(n.Context())
 			defer cancel()
 
-			host := strings.SplitN(r.Host, ":", 2)[0]
-			if len(host) > 0 && isd.IsDomain(host) {
-				name := "/ipns/" + host
-				_, err := n.Namesys.Resolve(ctx, name, nsopts.Depth(1))
-				if err == nil || err == namesys.ErrResolveRecursion {
-					r.URL.Path = name + r.URL.Path
+			// Is this one of our "known gateways"?
+			if gw, ok := KnownGateways[r.Host]; ok {
+				if hasPrefix(r.URL.Path, gw.PathPrefixes...) {
+					childMux.ServeHTTP(w, r)
+					return
+				}
+			} else if host, pathPrefix, ok := parseSubdomains(r.Host); ok {
+				if gw, ok := KnownGateways[host]; ok && gw.SupportsSubdomains {
+					// Always handle this with the gateway.
+					// We don't care if it's one of the
+					// valid path-prefixes.
+
+					r.URL.Path = pathPrefix + r.URL.Path
+					childMux.ServeHTTP(w, r)
+					return
 				}
 			}
+
+			host := strings.SplitN(r.Host, ":", 2)[0]
+			if len(host) == 0 || !isd.IsDomain(host) {
+				childMux.ServeHTTP(w, r)
+				return
+			}
+
+			name := "/ipns/" + host
+			_, err := n.Namesys.Resolve(ctx, name, nsopts.Depth(1))
+			if err == nil || err == namesys.ErrResolveRecursion {
+				r.URL.Path = name + r.URL.Path
+			}
 			childMux.ServeHTTP(w, r)
 		})
 		return childMux, nil
 	}
 }
+
+func parseSubdomains(host string) (newHost, pathPrefix string, ok bool) {
+	parts := strings.SplitN(host, ".", 3)
+	if len(parts) < 3 {
+		return "", "", false
+	}
+	switch parts[1] {
+	case "ipfs", "ipns", "p2p":
+		return parts[2], "/" + parts[1] + "/" + parts[0], true
+	}
+	return "", "", false
+}
+
+func hasPrefix(s string, prefixes ...string) bool {
+	for _, prefix := range prefixes {
+		if strings.HasPrefix(s, prefix) {
+			return true
+		}
+	}
+	return false
+}

go.sum

@@ -143,8 +143,6 @@ github.com/ipfs/go-ipfs-chunker v0.0.1 h1:cHUUxKFQ99pozdahi+uSC/3Y6HeRpi9oTeUHbE
 github.com/ipfs/go-ipfs-chunker v0.0.1/go.mod h1:tWewYK0we3+rMbOh7pPFGDyypCtvGcBFymgY4rSDLAw=
 github.com/ipfs/go-ipfs-cmdkit v0.0.1 h1:X6YXEAjUljTzevE6DPUKXSqcgf+4FXzcn5B957F5MXo=
 github.com/ipfs/go-ipfs-cmdkit v0.0.1/go.mod h1:9FtbMdUabcSqv/G4/8WCxSLxkZxn/aZEFrxxqnVcRbg=
-github.com/ipfs/go-ipfs-cmds v0.0.3 h1:QvNUE8lslNQghxXf6vzV1ZoMQCDDAtKG8f2oINiRew4=
-github.com/ipfs/go-ipfs-cmds v0.0.3/go.mod h1:1QVgxSgenZvOMGVC/XUTC7tJxRBGPLxYvpgPpCi3DUk=
 github.com/ipfs/go-ipfs-cmds v0.0.4 h1:Iq4I8irWw5TmHe/4pjSyYJLbYkkdMOgHVe8ofJmPa4k=
 github.com/ipfs/go-ipfs-cmds v0.0.4/go.mod h1:1QVgxSgenZvOMGVC/XUTC7tJxRBGPLxYvpgPpCi3DUk=
 github.com/ipfs/go-ipfs-config v0.0.1 h1:6ED08emzI1imdsAjixFi2pEyZxTVD5ECKtCOxLBx+Uc=
@@ -220,8 +218,6 @@ github.com/jbenet/go-cienv v0.0.0-20150120210510-1bb1476777ec h1:DQqZhhDvrTrEQ3Q
 github.com/jbenet/go-cienv v0.0.0-20150120210510-1bb1476777ec/go.mod h1:rGaEvXB4uRSZMmzKNLoXvTu1sfx+1kv/DojUlPrSZGs=
 github.com/jbenet/go-context v0.0.0-20150711004518-d14ea06fba99 h1:BQSFePA1RWJOlocH6Fxy8MmwDt+yVQYULKfN0RoTN8A=
 github.com/jbenet/go-context v0.0.0-20150711004518-d14ea06fba99/go.mod h1:1lJo3i6rXxKeerYnT8Nvf0QmHCRC1n8sfWVwXF2Frvo=
-github.com/jbenet/go-is-domain v0.0.0-20160119110217-ba9815c809e0 h1:qxMncUW0TzViA3REiN3/YgVOoekVtUtEY0O/j/Qlctg=
-github.com/jbenet/go-is-domain v0.0.0-20160119110217-ba9815c809e0/go.mod h1:I9DYFcJAixF5f9iOu/9oC451/bq+QDTaLGznkcJPWgg=
 github.com/jbenet/go-is-domain v1.0.2 h1:11r5MSptcNFZyBoqubBQnVMUKRWLuRjL1banaIk+iYo=
 github.com/jbenet/go-is-domain v1.0.2/go.mod h1:xbRLRb0S7FgzDBTJlguhDVwLYM/5yNtvktxj2Ttfy7Q=
 github.com/jbenet/go-random v0.0.0-20190219211222-123a90aedc0c h1:uUx61FiAa1GI6ZmVd2wf2vULeQZIKG66eybjNXKYCz4=