snapshot of https://github.com/grpc/grpc-go.git (master, 2026-09-15; blobs > 131072B omitted)

internal/googlecloud/googlecloud.go

@@ -0,0 +1,72 @@
+/*
+ *
+ * Copyright 2021 gRPC authors.
+ *
+ * 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.
+ *
+ */
+
+// Package googlecloud contains internal helpful functions for google cloud.
+package googlecloud
+
+import (
+	"runtime"
+	"strings"
+	"sync"
+
+	"google.golang.org/grpc/grpclog"
+	internalgrpclog "google.golang.org/grpc/internal/grpclog"
+)
+
+const logPrefix = "[googlecloud]"
+
+var (
+	vmOnGCEOnce sync.Once
+	vmOnGCE     bool
+
+	logger = internalgrpclog.NewPrefixLogger(grpclog.Component("googlecloud"), logPrefix)
+)
+
+// OnGCE returns whether the client is running on GCE.
+//
+// It provides similar functionality as metadata.OnGCE from the cloud library
+// package. We keep this to avoid depending on the cloud library module.
+func OnGCE() bool {
+	vmOnGCEOnce.Do(func() {
+		mf, err := manufacturer()
+		if err != nil {
+			logger.Infof("failed to read manufacturer, setting onGCE=false: %v")
+			return
+		}
+		vmOnGCE = isRunningOnGCE(mf, runtime.GOOS)
+	})
+	return vmOnGCE
+}
+
+// isRunningOnGCE checks whether the local system, without doing a network request, is
+// running on GCP.
+func isRunningOnGCE(manufacturer []byte, goos string) bool {
+	name := string(manufacturer)
+	switch goos {
+	case "linux":
+		name = strings.TrimSpace(name)
+		return name == "Google" || name == "Google Compute Engine"
+	case "windows":
+		name = strings.ReplaceAll(name, " ", "")
+		name = strings.ReplaceAll(name, "\n", "")
+		name = strings.ReplaceAll(name, "\r", "")
+		return name == "Google"
+	default:
+		return false
+	}
+}