fix: handle parameter routes in nextjs router

go.mod

@@ -1,3 +1,3 @@
 module go.sia.tech/web
 
-go 1.20
+go 1.21.7

hostd/hostd.go

@@ -5,17 +5,21 @@ import (
 	"io/fs"
 	"net/http"
 
-	"go.sia.tech/web/ui"
+	"go.sia.tech/web/internal/nextjs"
 )
 
 //go:embed all:assets/*
 var assets embed.FS
 
 // Handler returns an http.Handler that serves the hostd UI.
 func Handler() http.Handler {
-	fs, err := fs.Sub(assets, "assets")
+	assetFS, err := fs.Sub(assets, "assets")
 	if err != nil {
 		panic(err)
 	}
-	return ui.Handler(fs)
+	router, err := nextjs.NewRouter(assetFS.(fs.ReadDirFS))
+	if err != nil {
+		panic(err)
+	}
+	return router
 }

internal/nextjs/nextjs.go

@@ -0,0 +1,189 @@
+package nextjs
+
+import (
+	"fmt"
+	"io"
+	"io/fs"
+	"net/http"
+	"path"
+	"path/filepath"
+	"strings"
+	"time"
+)
+
+type (
+	// A node is a single node in the router tree.
+	node struct {
+		h        http.Handler
+		catchAll bool // true if this node is a catch-all node
+		optional bool // true if this node is an optional catch-all node
+		sub      map[string]node
+	}
+
+	// A Router is an HTTP request handler built to serve nextjs applications.
+	Router struct {
+		fsys fs.FS
+		root node
+	}
+)
+
+func (r *Router) serveErrorPage(status int, w http.ResponseWriter) {
+	errorPath := fmt.Sprintf("%d.html", status)
+
+	errorPage, err := r.fsys.Open(errorPath)
+	if err != nil {
+		http.Error(w, http.StatusText(status), status)
+		return
+	}
+	defer errorPage.Close()
+
+	w.WriteHeader(status)
+	io.Copy(w, errorPage)
+}
+
+// ServeHTTP implements the http.Handler interface.
+func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	fp := strings.Trim(req.URL.Path, "/")
+	ext := path.Ext(req.URL.Path)
+	if ext != "" { // most likely a static file
+		f, err := r.fsys.Open(fp)
+		if err == nil {
+			defer f.Close()
+			http.ServeContent(w, req, fp, time.Time{}, f.(io.ReadSeeker))
+			return
+		}
+	}
+
+	if fp == "" { // root path, serve index.html
+		r.root.h.ServeHTTP(w, req)
+		return
+	}
+
+	segments := strings.Split(fp, "/")
+	node := r.root
+	for i, segment := range segments {
+		if child, ok := node.sub[segment]; ok { // check for an exact path match
+			node = child
+		} else if child, ok := node.sub["[]"]; ok { // check for a parameter match
+			node = child
+		} else {
+			r.serveErrorPage(http.StatusNotFound, w) // no match found, serve 404
+			return
+		}
+
+		if node.catchAll {
+			if i == len(segments)-1 && !node.optional {
+				// if the catch-all is the last segment and it's not optional, serve 404
+				r.serveErrorPage(http.StatusNotFound, w)
+				return
+			}
+			node.h.ServeHTTP(w, req)
+			return
+		}
+	}
+
+	if node.h == nil { // no handler, serve 404
+		r.serveErrorPage(http.StatusNotFound, w)
+		return
+	}
+	node.h.ServeHTTP(w, req)
+}
+
+func httpFileHandler(fsys fs.FS, path string) http.Handler {
+	f, err := fsys.Open(path)
+	if err != nil {
+		panic(err)
+	}
+	f.Close()
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		f, err := fsys.Open(path)
+		if err != nil {
+			panic(err)
+		}
+		defer f.Close()
+
+		http.ServeContent(w, r, path, time.Time{}, f.(io.ReadSeeker))
+	})
+}
+
+func traverse(fs fs.ReadDirFS, fp string, segments []string, parent *node) error {
+	dir, err := fs.ReadDir(fp)
+	if err != nil {
+		return fmt.Errorf("failed to read directory %q: %w", strings.Join(segments, "/"), err)
+	}
+
+	for _, child := range dir {
+		childPath := filepath.Join(fp, child.Name())
+		name := child.Name()
+		ext := filepath.Ext(name)
+		name = strings.TrimSuffix(name, ext)
+
+		if !child.IsDir() && ext != ".html" {
+			continue
+		}
+
+		// add the route to the parent node
+		switch {
+		case strings.HasPrefix(name, "[[..."): // optional catch-all, ignore the remaining segments
+			parent.optional = true
+			parent.catchAll = true
+			parent.h = httpFileHandler(fs, childPath)
+			if len(parent.sub) != 0 {
+				return fmt.Errorf("failed to add catch-all route %q: parent has children", fp)
+			}
+			return nil
+		case strings.HasPrefix(name, "[..."): // required catch-all, ignore the remaining segments
+			parent.catchAll = true
+			parent.h = httpFileHandler(fs, childPath)
+			if len(parent.sub) != 0 {
+				return fmt.Errorf("failed to add required catch-all route %q: parent has children", fp)
+			}
+			return nil
+		case strings.HasPrefix(name, "["): // parameterized path
+			name = "[]"
+		}
+
+		// files may share the same name as a directory, so we need to check if the node already exists
+		childNode, ok := parent.sub[name]
+		if !ok {
+			childNode = node{
+				sub: make(map[string]node),
+			}
+		}
+
+		if !child.IsDir() {
+			if childNode.h != nil {
+				return fmt.Errorf("failed to add route %q: route already exists", childPath)
+			}
+			childNode.h = httpFileHandler(fs, childPath)
+		}
+
+		if child.IsDir() {
+			if err := traverse(fs, childPath, append(segments, name), &childNode); err != nil {
+				return err
+			}
+		}
+
+		parent.sub[name] = childNode
+	}
+	return nil
+}
+
+// NewRouter creates a new Router instance with the given fs.FS.
+func NewRouter(fs fs.ReadDirFS) (*Router, error) {
+	// the root node serves index.html on /
+	root := node{
+		h:   httpFileHandler(fs, "index.html"),
+		sub: make(map[string]node),
+	}
+
+	if err := traverse(fs, ".", nil, &root); err != nil {
+		return nil, err
+	}
+
+	return &Router{
+		root: root,
+		fsys: fs,
+	}, nil
+}

ui/ui_test.go → internal/nextjs/nextjs_test.go

@@ -1,4 +1,4 @@
-package ui
+package nextjs
 
 import (
 	"bytes"
@@ -159,12 +159,13 @@ func TestNextJSRouter(t *testing.T) {
 	fs.Add("404.html", []byte("404.html"))
 	fs.Add("foo.html", []byte("foo.html"))
 	fs.Add("foo/bar.html", []byte("foo/bar.html"))
-	fs.Add("foo/bar/[bar].html", []byte("foo/bar/[bar].html"))                   // parameterized path
-	fs.Add("foo/files/[...key].html", []byte("foo/files/[...key].html"))         // required catch-all
-	fs.Add("foo/objects/[[...key]].html", []byte("foo/objects/[[...key]].html")) // optional catch-all
+	fs.Add("foo/bar/[bar].html", []byte("foo/bar/[bar].html"))                                           // parameterized path
+	fs.Add("foo/files/[...key].html", []byte("foo/files/[...key].html"))                                 // required catch-all
+	fs.Add("foo/objects/[[...key]].html", []byte("foo/objects/[[...key]].html"))                         // optional catch-all
+	fs.Add("buckets/[bucket]/files/[[...path]].html", []byte("buckets/[bucket]/files/[[...path]].html")) // param and catch-all
 	fs.Add("assets/foo.jpg", []byte("assets/foo.jpg"))
 
-	router, err := newNextJSRouter(fs)
+	router, err := NewRouter(fs)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -199,8 +200,10 @@ func TestNextJSRouter(t *testing.T) {
 		{"/foo/objects/bar", "foo/objects/[[...key]].html", http.StatusOK},
 		{"/foo/objects/bar/baz", "foo/objects/[[...key]].html", http.StatusOK},
 		{"/foo/objects/bar/baz/", "foo/objects/[[...key]].html", http.StatusOK},
-		{"/foo/objects/bar/biz.baz", "foo/objects/[[...key]].html", http.StatusOK}, // with dots in path
-		{"/foo/biz.baz", "404.html", http.StatusNotFound},                          // with dots in path
+		{"/foo/objects/bar/biz.baz", "foo/objects/[[...key]].html", http.StatusOK},                             // with dots in path
+		{"/foo/biz.baz", "404.html", http.StatusNotFound},                                                      // with dots in path
+		{"/buckets/default/files/path/to/directory", "buckets/[bucket]/files/[[...path]].html", http.StatusOK}, // param and catch-all
+		{"/buckets/default/files/path/to/directory/", "buckets/[bucket]/files/[[...path]].html", http.StatusOK},
 	}
 
 	makeRequest := func(path string, status int) ([]byte, error) {

renterd/renterd.go

@@ -5,17 +5,21 @@ import (
 	"io/fs"
 	"net/http"
 
-	"go.sia.tech/web/ui"
+	"go.sia.tech/web/internal/nextjs"
 )
 
 //go:embed all:assets/*
 var assets embed.FS
 
 // Handler returns an http.Handler that serves the renterd UI.
 func Handler() http.Handler {
-	fs, err := fs.Sub(assets, "assets")
+	assetFS, err := fs.Sub(assets, "assets")
 	if err != nil {
 		panic(err)
 	}
-	return ui.Handler(fs)
+	router, err := nextjs.NewRouter(assetFS.(fs.ReadDirFS))
+	if err != nil {
+		panic(err)
+	}
+	return router
 }