Move the k8s code generator.

cmd/k8scopy/internal/writer.go

@@ -0,0 +1,40 @@
+// Copyright 2020 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package internal
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+)
+
+type writer struct {
+	root string
+	f    *os.File
+}
+
+func newWriter(toDir, name string) (*writer, error) {
+	if err := os.MkdirAll(toDir, 0755); err != nil {
+		log.Printf("unable to create directory: %s", toDir)
+		return nil, err
+	}
+	n := filepath.Join(toDir, name)
+	f, err := os.Create(n)
+	if err != nil {
+		return nil, fmt.Errorf("unable to create `%s`; %v", n, err)
+	}
+	return &writer{root: toDir, f: f}, nil
+}
+
+func (w *writer) close() {
+	w.f.Close()
+}
+
+func (w *writer) write(line string) {
+	if _, err := w.f.WriteString(line + "\n"); err != nil {
+		log.Printf("Trouble writing: %s", line)
+		log.Fatalf("Error: %s", err)
+	}
+}