Get reproxytool to start building on Windows

Bug: n/a

Tested: Ran the build on windows and confirmed it works, also ensured the server works on Windows
Change-Id: Id8ad01f6f4e297e548573beb7fb43300dff202a3
GitOrigin-RevId: 03bf46b20242fe09836396dd92249f0e6623c122

cmd/reproxytool/BUILD.bazel

@@ -20,6 +20,7 @@ go_binary(
     embed = [":reproxytool_lib"],
     target_compatible_with = select({
         "@platforms//os:linux": [],
+        "@platforms//os:windows": [],
         "//conditions:default": ["@platforms//:incompatible"],
     }),
     visibility = ["//visibility:public"],

internal/pkg/logrecordserver/logrecordserver.go

@@ -20,6 +20,7 @@ import (
 	"encoding/json"
 	"io/fs"
 	"net/http"
+	"path/filepath"
 	"sync"
 
 	"github.com/bazelbuild/reclient/internal/pkg/logger"
@@ -127,8 +128,9 @@ func (lr *Server) Start(listenAddr string) {
 	if err != nil {
 		log.Fatal(err)
 	}
+	basePath := filepath.Join("internal", "pkg", "logrecordserver", "ui", "app", "dist", "reproxyui", "browser")
 	log.V(1).Infof("Loaded JS app from embedded tar file (size=%v)", len(tarAngularApp))
-	indexFS, _ := fs.Sub(tarfs, "internal/pkg/logrecordserver/ui/app/dist/reproxyui/browser")
+	indexFS, _ := fs.Sub(tarfs, basePath)
 	fs := http.FileServer(http.FS(indexFS))
 	r.PathPrefix("/").Handler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		fs.ServeHTTP(w, r)

internal/pkg/logrecordserver/ui/BUILD.bazel

@@ -24,6 +24,7 @@ genrule(
     exec_properties = {"dockerNetwork": "standard"},
     target_compatible_with = select({
         "@platforms//os:linux": [],
+        "@platforms//os:windows": [],
         "//conditions:default": ["@platforms//:incompatible"],
     }),
     toolchains = ["@nodejs_toolchains//:resolved_toolchain"],

internal/pkg/tarfs/tarfs.go

@@ -25,6 +25,8 @@ import (
 	"io/fs"
 	"os"
 	"path/filepath"
+	"runtime"
+	"strings"
 	"time"
 
 	log "github.com/golang/glog"
@@ -41,10 +43,14 @@ type TarFS struct {
 
 // Open creates a new open file.
 func (t *TarFS) Open(name string) (fs.File, error) {
+	if runtime.GOOS == "windows" {
+		name = strings.ReplaceAll(name, "/", "\\")
+	}
 	log.V(3).Infof("TarFS.Open: %s", name)
 	if f, ok := t.tarContents[name]; ok {
 		return f.NewOpenFile(), nil
 	}
+	log.V(3).Infof("TarFS.Open: failed to find %v, tar=%v", name, t.tarContents)
 	return nil, fs.ErrNotExist
 }