Further work; tidying up, begin cmdline tool

cmd/htpacker/pack.go

@@ -0,0 +1,75 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+
+	"github.com/lwithers/htpack/packer"
+	"github.com/spf13/cobra"
+	yaml "gopkg.in/yaml.v2"
+)
+
+var packCmd = &cobra.Command{
+	Use:   "pack",
+	Short: "creates a packfile from a YAML spec or set of files/dirs",
+	RunE: func(c *cobra.Command, args []string) error {
+		spec, err := c.Flags().GetString("spec")
+		if err != nil {
+			return err
+		}
+
+		if spec == "" {
+			if len(args) == 0 {
+				return errors.New("need --yaml, " +
+					"or one or more filenames")
+			}
+			err = PackFiles(c, args)
+		} else {
+			if len(args) != 0 {
+				return errors.New("cannot specify files " +
+					"when using --yaml")
+			}
+			err = PackSpec(c, spec)
+		}
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(1)
+		}
+
+		return nil
+	},
+}
+
+func init() {
+	packCmd.Flags().StringP("out", "O", "",
+		"Output filename")
+	packCmd.MarkFlagRequired("out")
+	packCmd.Flags().StringP("spec", "y", "",
+		"YAML specification file (if not present, just pack files)")
+	packCmd.Flags().StringP("chdir", "C", "",
+		"Change to directory before searching for input files")
+}
+
+func PackFiles(c *cobra.Command, args []string) error {
+	// TODO
+	return errors.New("not implemented yet")
+}
+
+func PackSpec(c *cobra.Command, spec string) error {
+	raw, err := ioutil.ReadFile(spec)
+	if err != nil {
+		return err
+	}
+
+	var ftp packer.FilesToPack
+	if err := yaml.UnmarshalStrict(raw, &ftp); err != nil {
+		return fmt.Errorf("parsing YAML spec %s: %v", spec, err)
+	}
+
+	// TODO: chdir
+
+	out, _ := c.Flags().GetString("out")
+	return packer.Pack(ftp, out)
+}