Environment variable NO_WINDOWS_SERVICE to force interactive mode on Windows

cmd/otelcol/main_windows.go

@@ -18,25 +18,39 @@ package main
 
 import (
 	"fmt"
+	"os"
 
 	"golang.org/x/sys/windows/svc"
 
 	"go.opentelemetry.io/collector/service"
 )
 
 func run(params service.Parameters) error {
-	isInteractive, err := svc.IsAnInteractiveSession()
-	if err != nil {
-		return fmt.Errorf("failed to determine if we are running in an interactive session %w", err)
-	}
-
-	if isInteractive {
+	if useInteractiveMode, err := checkUseInteractiveMode(); err != nil {
+		return err
+	} else if useInteractiveMode {
 		return runInteractive(params)
 	} else {
 		return runService(params)
 	}
 }
 
+func checkUseInteractiveMode() (bool, error) {
+	// If environment variable NO_WINDOWS_SERVICE is set with any value other
+	// than 0, use interactive mode instead of running as a service. This should
+	// be set in case running as a service is not possible or desired even
+	// though the current session is not detected to be interactive
+	if value, present := os.LookupEnv("NO_WINDOWS_SERVICE"); present && value != "0" {
+		return true, nil
+	}
+
+	if isInteractiveSession, err := svc.IsAnInteractiveSession(); err != nil {
+		return false, fmt.Errorf("failed to determine if we are running in an interactive session %w", err)
+	} else {
+		return isInteractiveSession, nil
+	}
+}
+
 func runService(params service.Parameters) error {
 	// do not need to supply service name when startup is invoked through Service Control Manager directly
 	if err := svc.Run("", service.NewWindowsService(params)); err != nil {

docs/troubleshooting.md

@@ -258,3 +258,11 @@ More often than not, exporting data does not work because of a network
 configuration issue. This could be due to a firewall, DNS, or proxy
 issue. Note that the Collector does have
 [proxy support](https://github.com/open-telemetry/opentelemetry-collector/tree/master/exporter#proxy-support).
+
+### Startup failing in Windows Docker containers
+
+The process may fail to start in a Windows Docker container with the following
+error: `The service process could not connect to the service controller`. In
+this case the `NO_WINDOWS_SERVICE=1` environment variable should be set to force
+the collector to be started as if it were running in an interactive terminal,
+without attempting to run as a Windows service.