internal/gomote: fix path to buildlet

This change modifies the Python script used to bootstrap the gomote
instance. It fixes the paths to files on Windows instances. The time
we wait for an instance to be fully bootstrapped has been increased to
10 minutes from 5 mintes because of the time needed to bootstrap macOS
instances.

Change-Id: I257e9c392b717d690b1ba3bd847fa987ead485e6
Reviewed-on: https://go-review.googlesource.com/c/build/+/565855
Auto-Submit: Carlos Amedee <carlos@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

internal/gomote/swarming.go

@@ -816,7 +816,7 @@ func (ss *SwarmingServer) startNewSwarmingTask(ctx context.Context, name string,
 // waitForInstanceOrFailure waits for either the swarming task to enter a failed state or the successful connection from
 // a buildlet client.
 func (ss *SwarmingServer) waitForInstanceOrFailure(ctx context.Context, taskID, name string) (buildlet.Client, error) {
-	queryCtx, cancel := context.WithTimeout(ctx, 5*time.Minute)
+	queryCtx, cancel := context.WithTimeout(ctx, 10*time.Minute)
 
 	checkForTaskFailure := func(pollCtx context.Context) <-chan error {
 		errCh := make(chan error, 1)
@@ -1030,14 +1030,14 @@ if __name__ == "__main__":
         ext = ".exe"
     sep = "/"
     if sys.platform == "win32":
-        sep = "\\"
-    buildlet_name = "." + sep + "buildlet"
-    if os.path.exists(buildlet_name):
-        os.remove(buildlet_name)
-    urllib.request.urlretrieve("https://storage.googleapis.com/go-builder-data/buildlet.%s-%s", buildlet_name)
-    make_executable(os.getcwd() + sep + buildlet_name)
-    buildlet_name = "."+sep + buildlet_name
-    subprocess.run(["%s", buildlet_name, "--coordinator=gomotessh.golang.org:443", "--reverse-type=swarming-task", "-swarming-bot", "-halt=false"], shell=False, env=os.environ.copy())
+        sep = "\\\\"
+    buildlet_file = "buildlet" + ext
+    buildlet_path = "." + sep + buildlet_file
+    if os.path.exists(buildlet_path):
+        os.remove(buildlet_path)
+    urllib.request.urlretrieve("https://storage.googleapis.com/go-builder-data/buildlet.%s-%s", buildlet_path)
+    make_executable(os.getcwd() + sep + buildlet_file)
+    subprocess.run(["%s", buildlet_path, "--coordinator=gomotessh.golang.org:443", "--reverse-type=swarming-task", "-swarming-bot", "-halt=false"], shell=False, env=os.environ.copy())
 `
 	return fmt.Sprintf(cmd, goos, goarch, golangbuildBin)
 }
@@ -1066,7 +1066,7 @@ func (ss *SwarmingServer) newSwarmingTaskWithGolangbuild(ctx context.Context, na
 		packages = append(packages,
 			&swarmpb.CipdPackage{Path: "tools", PackageName: "infra/3pp/tools/cpython3/" + cipdPlatform, Version: "latest"})
 	case "windows":
-		golangbuildBin = `tools\bin\golangbuild.exe`
+		golangbuildBin = `tools\\bin\\golangbuild.exe`
 		pythonBin = `tools\bin\python3.exe`
 		packages = append(packages, &swarmpb.CipdPackage{Path: "tools", PackageName: "infra/3pp/tools/cpython3/" + cipdPlatform, Version: "latest"})
 	}