1 files changed, 277 insertions, 0 deletions
diff --git a/src/glaze.go b/src/glaze.go
new file mode 100644
index 0000000..d0bc3e0
--- /dev/null
+++ b/src/glaze.go
@@ -0,0 +1,277 @@
+package glaze
+
+import (
+	"context"
+	"errors"
+	"flag"
+	"fmt"
+	"io"
+	"io/fs"
+	"net"
+	"net/http"
+	"net/url"
+	"os"
+	"strings"
+	"syscall"
+
+
+	g "gobang"
+)
+
+
+
+type patternPath struct {}
+
+type pathInfo struct {
+	pattern    string
+	path       string
+	label      string
+	fileHandle *os.File
+	fileInfo   fs.FileInfo
+}
+
+
+
+const (
+	xattrTryIndexHtml     = "user.glaze.try-index-html"
+	xattrDirectoryListing = "user.glaze.directory-listing"
+	xattrExpectedValue    = "true"
+)
+
+
+
+func httpError(w http.ResponseWriter, code int, err error) {
+	t := http.StatusText(code)
+	g.Error(
+		err.Error(), "http-server-error",
+		"code", code,
+		"error", err,
+		"status-text", t,
+	)
+	http.Error(w, t, code)
+}
+
+func withTrailingSlash(path string) string {
+	if strings.HasSuffix(path, "/") {
+		return path
+	} else {
+		return path + "/"
+	}
+}
+
+func adjustPattern(pattern string) string {
+	if pattern == "*" {
+		return "/"
+	} else if strings.HasSuffix(pattern, "*") {
+		return pattern[0:len(pattern) - 1]
+	} else {
+		return pattern + "{$}"
+	}
+}
+
+func handleSymlink(info pathInfo, w http.ResponseWriter, r *http.Request) error {
+	linked, err := os.Readlink(info.path)
+	if err != nil {
+		return err
+	}
+
+	// From http.Redirect():
+	//
+	// > If the Content-Type header has not been set,
+	// > Redirect sets it to "text/html; charset=utf-8" and
+	// > writes a small HTML body.
+	//
+	// 🙄
+	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
+
+	http.Redirect(w, r, linked, http.StatusMovedPermanently)
+	return nil
+}
+
+func handleProxy(info pathInfo, w http.ResponseWriter, r *http.Request) error {
+	target, err := url.Parse(info.path)
+	if err != nil {
+		return err
+	}
+
+	target.Scheme = "http"
+	target.Host   = "localhost"
+	httpClient := http.Client {
+		Transport: &http.Transport {
+			DialContext: func(_ context.Context, _ string, _ string) (net.Conn, error) {
+				return net.Dial("unix", info.path)
+			},
+		},
+	}
+
+	r.URL.Scheme = target.Scheme
+	r.URL.Host   = target.Host
+	r.RequestURI = ""
+	response, err := httpClient.Do(r)
+	if err != nil {
+		return err
+	}
+	for k, vArr := range response.Header {
+		for _, v := range vArr {
+			w.Header().Add(k, v)
+		}
+	}
+	w.WriteHeader(response.StatusCode)
+	io.Copy(w, response.Body)
+	return nil
+}
+
+func handleFile(info pathInfo, w http.ResponseWriter, r *http.Request) error {
+	http.ServeContent(w, r, info.fileInfo.Name(), info.fileInfo.ModTime(), info.fileHandle)
+	return nil
+}
+
+func getXattr(path string, name string) (string, error) {
+	data := make([]byte, 256)
+	i, err := syscall.Getxattr(path, name, data)
+	fmt.Println("i", i)
+	if err != nil {
+		return "", err
+	}
+	return string(data[0:i]), nil
+}
+
+func handleDirectoryTarget(info pathInfo, w http.ResponseWriter, r *http.Request) error {
+	targetPath := withTrailingSlash(info.path) + r.URL.Path
+	newInfo, fn, err := handlerForDynPath(targetPath)
+	if err != nil {
+		return err
+	}
+
+	if (newInfo.label != "directory") {
+		return fn(newInfo, w, r)
+	}
+
+	indexHtmlXattr, err := getXattr(targetPath, xattrTryIndexHtml)
+	if err == nil && string(indexHtmlXattr) == xattrExpectedValue {
+		newPath := withTrailingSlash(targetPath) + "index.html"
+		_, err := os.Open(newPath)
+		if err == nil {
+			return fn(newInfo, w, r)
+		}
+	}
+
+	dirListXattr, err := getXattr(targetPath, xattrDirectoryListing)
+	if err == nil && string(dirListXattr) == xattrExpectedValue {
+		http.FileServer(http.Dir(newInfo.path)).ServeHTTP(w, r)
+		return nil
+	}
+
+	http.Error(w, "Forbidden", http.StatusForbidden)
+	return nil
+}
+
+func handlerFuncFor(mode fs.FileMode) (string, func(pathInfo, http.ResponseWriter, *http.Request) error) {
+	if mode.Type() == fs.ModeSymlink {
+		return "symlink", handleSymlink
+	} else if mode.Type() == fs.ModeSocket {
+		return "socket", handleProxy
+	} else if !mode.IsDir() {
+		return "file", handleFile
+	} else {
+		return "directory", handleDirectoryTarget
+	}
+}
+
+func handlerForDynPath(path string) (pathInfo, func(pathInfo, http.ResponseWriter, *http.Request) error, error) {
+	var info pathInfo
+	fileHandle, err := os.Open(path)
+	if err != nil {
+		return info, nil, err
+	}
+
+	fileInfo, err := os.Lstat(path)
+	if err != nil {
+		return info, nil, err
+	}
+
+	label, fn := handlerFuncFor(fileInfo.Mode())
+	g.Info("Handler picked", "handler-picked", "label", label)
+	info = pathInfo {
+		path:       path,
+		label:      label,
+		fileHandle: fileHandle,
+		fileInfo:   fileInfo,
+	}
+	return info, fn, nil
+}
+
+func handlerFor(path string) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		id := g.NewUUID()
+		g.Info("in-request", "in-request", "path", path, "id", id)
+		defer g.Info("in-response", "in-response", "path", path, "id", id)
+
+		info, fn, err := handlerForDynPath(path)
+		if err != nil {
+			httpError(w, http.StatusInternalServerError, err)
+			return
+		}
+
+		err = fn(info, w, r)
+		if err != nil {
+			httpError(w, http.StatusInternalServerError, err)
+			return
+		}
+	})
+}
+
+func (i *patternPath) String() string {
+	return ""
+}
+
+func (_ *patternPath) Set(value string) error {
+	arr := strings.Split(value, ":")
+	if len(arr) != 2 {
+		return errors.New("Bad value for path pattern: " + value)
+	}
+
+	pattern := adjustPattern(arr[0])
+	path    := arr[1]
+
+	http.Handle(pattern, http.StripPrefix(pattern, handlerFor(path)))
+	return nil
+}
+
+func parseArgs(args []string) string {
+	var pat patternPath
+	fs := flag.NewFlagSet(args[0], flag.ExitOnError)
+	fs.Var(&pat, "P", "")
+	fs.Parse(args[1:])
+	if fs.NArg() != 1 {
+		fmt.Fprintf(
+			os.Stderr,
+			"Usage: %s [ -P PATTERN:PATH ]... LISTEN.socket\n",
+			args[0],
+		)
+		os.Exit(2)
+	}
+	return fs.Arg(0)
+}
+
+func listen(fromAddr string) net.Listener {
+	listener, err := net.Listen("unix", fromAddr)
+	g.FatalIf(err)
+	g.Info("Started listening", "listen-start", "from-address", fromAddr)
+	return listener
+}
+
+func start(listener net.Listener) {
+	server := http.Server {}
+	err := server.Serve(listener)
+	g.FatalIf(err)
+}
+
+
+
+func Main() {
+	g.Init()
+	addr := parseArgs(os.Args)
+	listener := listen(addr)
+	start(listener)
+}