Added named pipe option for stdin

.devcontainer/Dockerfile

@@ -0,0 +1,19 @@
+# See here for image contents: https://github.com/microsoft/vscode-dev-containers/tree/v0.194.3/containers/go/.devcontainer/base.Dockerfile
+
+# [Choice] Go version: 1, 1.16, 1.17
+ARG VARIANT="1.17"
+FROM mcr.microsoft.com/vscode/devcontainers/go:0-${VARIANT}
+
+# [Choice] Node.js version: none, lts/*, 16, 14, 12, 10
+ARG NODE_VERSION="none"
+RUN if [ "${NODE_VERSION}" != "none" ]; then su vscode -c "umask 0002 && . /usr/local/share/nvm/nvm.sh && nvm install ${NODE_VERSION} 2>&1"; fi
+
+# [Optional] Uncomment this section to install additional OS packages.
+# RUN apt-get update && export DEBIAN_FRONTEND=noninteractive \
+#     && apt-get -y install --no-install-recommends <your-package-list-here>
+
+# [Optional] Uncomment the next line to use go get to install anything else you need
+# RUN go get -x <your-dependency-or-tool>
+
+# [Optional] Uncomment this line to install global node packages.
+# RUN su vscode -c "source /usr/local/share/nvm/nvm.sh && npm install -g <your-package-here>" 2>&1

.devcontainer/devcontainer.json

@@ -0,0 +1,37 @@
+// For format details, see https://aka.ms/devcontainer.json. For config options, see the README at:
+// https://github.com/microsoft/vscode-dev-containers/tree/v0.194.3/containers/go
+{
+	"name": "Go",
+	"build": {
+		"dockerfile": "Dockerfile",
+		"args": {
+			// Update the VARIANT arg to pick a version of Go: 1, 1.16, 1.17
+			"VARIANT": "1.17",
+			// Options
+			"NODE_VERSION": "lts/*"
+		}
+	},
+	"runArgs": [ "--cap-add=SYS_PTRACE", "--security-opt", "seccomp=unconfined" ],
+
+	// Set *default* container specific settings.json values on container create.
+	"settings": {
+		"go.toolsManagement.checkForUpdates": "local",
+		"go.useLanguageServer": true,
+		"go.gopath": "/go",
+		"go.goroot": "/usr/local/go"
+	},
+
+	// Add the IDs of extensions you want installed when the container is created.
+	"extensions": [
+		"golang.Go"
+	],
+
+	// Use 'forwardPorts' to make a list of ports inside the container available locally.
+	// "forwardPorts": [],
+
+	// Use 'postCreateCommand' to run commands after the container is created.
+	// "postCreateCommand": "go version",
+
+	// Comment out connect as root instead. More info: https://aka.ms/vscode-remote/containers/non-root.
+	"remoteUser": "vscode"
+}

.gitignore

@@ -2,4 +2,5 @@
 /mc-server-runner.exe
 /*.iml
 /.idea/
-/tmp/
+/tmp/
+/.vscode/

go.mod

@@ -3,9 +3,7 @@ module github.com/itzg/mc-server-runner
 go 1.13
 
 require (
-	github.com/itzg/go-flagsfiller v1.4.2
+	github.com/itzg/go-flagsfiller v1.6.0
 	github.com/itzg/zapconfigs v0.1.0
-	github.com/karrick/godirwalk v1.15.5
-	github.com/stretchr/testify v1.4.0
 	go.uber.org/zap v1.13.0
 )

go.sum

@@ -7,12 +7,10 @@ github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSs
 github.com/google/renameio v0.1.0/go.mod h1:KWCgfxg9yswjAJkECMjeO8J8rahYeXnNhOm40UhjYkI=
 github.com/iancoleman/strcase v0.0.0-20191112232945-16388991a334 h1:VHgatEHNcBFEB7inlalqfNqw65aNkM1lGX2yt3NmbS8=
 github.com/iancoleman/strcase v0.0.0-20191112232945-16388991a334/go.mod h1:SK73tn/9oHe+/Y0h39VT4UCxmurVJkR5NA7kMEAOgSE=
-github.com/itzg/go-flagsfiller v1.4.2 h1:aQRyQ9/ps111FZYGhzxgKYiOewE7zbAks7rxF49Qlm8=
-github.com/itzg/go-flagsfiller v1.4.2/go.mod h1:mfQgTahSs4OHn8PYev2Wwi1LJXUiYiGuZVCpBLxzbYs=
+github.com/itzg/go-flagsfiller v1.6.0 h1:ovVbK2IM18AY5kgRZ/cb7yQrdSgyXmlaTUyDsx6k/Dk=
+github.com/itzg/go-flagsfiller v1.6.0/go.mod h1:mfQgTahSs4OHn8PYev2Wwi1LJXUiYiGuZVCpBLxzbYs=
 github.com/itzg/zapconfigs v0.1.0 h1:Gokocm8VaTNnZjvIiVA5NEhzZ1v7lEyXY/AbeBmq6YQ=
 github.com/itzg/zapconfigs v0.1.0/go.mod h1:y4dArgRUOFbGRkUNJ8XSSw98FGn03wtkvMPy+OSA5Rc=
-github.com/karrick/godirwalk v1.15.5 h1:ErdAEFW/cKxQ5+9Gm/hopxB8ki21/di+vyNb9mHnHrA=
-github.com/karrick/godirwalk v1.15.5/go.mod h1:j4mkqPuvaLI8mp1DroR3P6ad7cyYd4c1qeJ3RV7ULlk=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=

main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"context"
 	"flag"
 	"fmt"
 	"io"
@@ -25,6 +26,7 @@ type Args struct {
 	StopServerAnnounceDelay time.Duration `default:"0s" usage:"Amount of time in Golang duration to wait after announcing server shutdown"`
 	DetachStdin             bool          `usage:"Don't forward stdin and allow process to be put in background"`
 	Shell                   string        `usage:"When set, pass the arguments to this shell"`
+	NamedPipe               string        `usage:"Optional path to create and read a named pipe for console input"`
 }
 
 func main() {
@@ -103,6 +105,15 @@ func main() {
 		}()
 	}
 
+	ctx, cancel := context.WithCancel(context.Background())
+
+	if args.NamedPipe != "" {
+		err2 := handleNamedPipe(ctx, args.NamedPipe, stdin)
+		if err2 != nil {
+			logger.Fatal("Failed to setup named pipe", zap.Error(err2))
+		}
+	}
+
 	cmdExitChan := make(chan int, 1)
 
 	go func() {
@@ -154,8 +165,8 @@ func main() {
 			}
 
 		case exitCode := <-cmdExitChan:
+			cancel()
 			logger.Info("Done")
-			defer logger.Sync()
 			os.Exit(exitCode)
 		}
 	}
@@ -216,22 +227,3 @@ func stopViaConsole(logger *zap.Logger, stdin io.Writer) {
 		logger.Error("Failed to write stop command to server console", zap.Error(err))
 	}
 }
-
-func fillServerJar(args []string, serverJar string) ([]string, error) {
-	result := make([]string, len(args))
-	found := false
-	for i, arg := range args {
-		if arg == "_SERVERJAR_" {
-			found = true
-			result[i] = serverJar
-		} else {
-			result[i] = arg
-		}
-	}
-
-	if !found {
-		return nil, fmt.Errorf("unable to locate _SERVERJAR_ placeholder in args")
-	} else {
-		return result, nil
-	}
-}

named_pipe.go

@@ -0,0 +1,13 @@
+//go:build !linux
+
+package main
+
+import (
+	"go.uber.org/zap"
+	"io"
+)
+
+func handleNamedPipe(ctx context.Context, path string, stdin io.Writer) error {
+	// does nothing on non-linux
+	return nil
+}

named_pipe_linux.go

@@ -0,0 +1,47 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os"
+	"syscall"
+)
+
+func handleNamedPipe(ctx context.Context, path string, stdin io.Writer) error {
+	fi, statErr := os.Stat(path)
+	if statErr != nil {
+		if os.IsNotExist(statErr) {
+			mkErr := syscall.Mkfifo(path, 0666)
+			if mkErr != nil {
+				return fmt.Errorf("failed to create named pipe: %w", mkErr)
+			}
+		} else {
+			return fmt.Errorf("failed to stat named pipe: %w", statErr)
+		}
+	} else {
+		// already exists...named pipe?
+		if fi.Mode().Type()&os.ModeNamedPipe == 0 {
+			return fmt.Errorf("existing path '%s' is not a named pipe", path)
+		}
+	}
+
+	f, openErr := os.Open(path)
+	if openErr != nil {
+		return fmt.Errorf("failed to open named pipe: %w", openErr)
+	}
+
+	go func() {
+		_, _ = io.Copy(stdin, f)
+		// copy finished due to file closure (or error)
+		os.Remove(path)
+	}()
+
+	go func() {
+		<-ctx.Done()
+		// kick the copy operation above
+		f.Close()
+	}()
+
+	return nil
+}