feat(compute/metadata): add sys check for windows OnGCE (#10521)

Tested the windows detection on a Windows VM on cloud.

Fixes: https://togithub.com/googleapis/google-api-go-client/issues/2117

compute/metadata/go.mod

@@ -1,3 +1,5 @@
 module cloud.google.com/go/compute/metadata
 
 go 1.20
+
+require golang.org/x/sys v0.22.0

compute/metadata/go.sum

@@ -0,0 +1,2 @@
+golang.org/x/sys v0.22.0 h1:RI27ohtqKCnwULzJLqkv897zojh5/DwS/ENaMzUOaWI=
+golang.org/x/sys v0.22.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=

compute/metadata/metadata.go

@@ -28,7 +28,6 @@ import (
 	"net/http"
 	"net/url"
 	"os"
-	"runtime"
 	"strings"
 	"sync"
 	"time"
@@ -190,20 +189,6 @@ func testOnGCE() bool {
 	return <-resc
 }
 
-// systemInfoSuggestsGCE reports whether the local system (without
-// doing network requests) suggests that we're running on GCE. If this
-// returns true, testOnGCE tries a bit harder to reach its metadata
-// server.
-func systemInfoSuggestsGCE() bool {
-	if runtime.GOOS != "linux" {
-		// We don't have any non-Linux clues available, at least yet.
-		return false
-	}
-	slurp, _ := os.ReadFile("/sys/class/dmi/id/product_name")
-	name := strings.TrimSpace(string(slurp))
-	return name == "Google" || name == "Google Compute Engine"
-}
-
 // Subscribe calls Client.SubscribeWithContext on the default client.
 //
 // Deprecated: Please use the context aware variant [SubscribeWithContext].

compute/metadata/syscheck.go

@@ -0,0 +1,26 @@
+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build !windows && !linux
+
+package metadata
+
+// systemInfoSuggestsGCE reports whether the local system (without
+// doing network requests) suggests that we're running on GCE. If this
+// returns true, testOnGCE tries a bit harder to reach its metadata
+// server.
+func systemInfoSuggestsGCE() bool {
+	// We don't currently have checks for other GOOS
+	return false
+}

compute/metadata/syscheck_linux.go

@@ -0,0 +1,28 @@
+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build linux
+
+package metadata
+
+import (
+	"os"
+	"strings"
+)
+
+func systemInfoSuggestsGCE() bool {
+	b, _ := os.ReadFile("/sys/class/dmi/id/product_name")
+	name := strings.TrimSpace(string(b))
+	return name == "Google" || name == "Google Compute Engine"
+}

compute/metadata/syscheck_windows.go

@@ -0,0 +1,38 @@
+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build windows
+
+package metadata
+
+import (
+	"strings"
+
+	"golang.org/x/sys/windows/registry"
+)
+
+func systemInfoSuggestsGCE() bool {
+	k, err := registry.OpenKey(registry.LOCAL_MACHINE, `SYSTEM\HardwareConfig\Current`, registry.QUERY_VALUE)
+	if err != nil {
+		return false
+	}
+	defer k.Close()
+
+	s, _, err := k.GetStringValue("SystemProductName")
+	if err != nil {
+		return false
+	}
+	s = strings.TrimSpace(s)
+	return strings.HasPrefix(s, "Google")
+}