Add a tool to manage modules

cmd/fsplmod/doc.go

@@ -0,0 +1,2 @@
+// fsplmod manages FSPL modules.
+package main

cmd/fsplmod/main.go

@@ -0,0 +1,107 @@
+package main
+
+import "io"
+import "os"
+import "path/filepath"
+import "github.com/google/uuid"
+import "git.tebibyte.media/fspl/fspl/cli"
+import "git.tebibyte.media/fspl/fspl/lexer"
+import "git.tebibyte.media/fspl/fspl/entity"
+import "git.tebibyte.media/fspl/fspl/parser/meta"
+import ferrors "git.tebibyte.media/fspl/fspl/errors"
+
+func main () {
+	// CLI: application
+	applicationCli := cli.New (
+		"Manage FSPL modules",
+		cli.NewHelp())
+	
+	// CLI: new
+	newCli := cli.New (
+		"Create a new module in the specified directory",
+		cli.NewHelp())
+	newCli.Syntax = "[OPTION]... DIRECTORY"
+	applicationCli.AddSub("new", newCli)
+	
+	// CLI: bump
+	bumpCli := cli.New (
+		"Re-generate the UUID of a module",
+		cli.NewHelp())
+	newCli.Syntax = "[OPTION]... DIRECTORY"
+	applicationCli.AddSub("bump", bumpCli)
+
+	handleErr := func (cli *cli.Cli, err error, code int) {
+		if err == nil { return }
+		cli.Errorln(ferrors.Format(err))
+		os.Exit(code)
+	}
+	
+	switch cli := applicationCli.ParseOrExit(os.Args); cli {
+	case newCli:
+		// Create a new module in the specified directory
+		if len(cli.Args) != 1 {
+			cli.Errorln("please specify one module directory")
+			cli.Usage()
+			os.Exit(2)
+		}
+		
+		dir := cli.Args[0]
+		_, err := os.Stat(dir)
+		if err != nil {
+			err := os.Mkdir(dir, 0755)
+			handleErr(cli, err, 1)
+		}
+
+		moduleId, err := uuid.NewRandom()
+		handleErr(cli, err, 1)
+		cli.Println("creating module", moduleId, "in", dir)
+		metadataPath := filepath.Join(dir, "fspl.mod")
+		
+		file, err := os.OpenFile (
+			metadataPath,
+			os.O_CREATE | os.O_WRONLY | os.O_TRUNC,
+			0644)
+		handleErr(cli, err, 1)
+		defer file.Close()
+		
+		meta := entity.Metadata {
+			UUID: moduleId,
+		}
+		_, err = io.WriteString(file, meta.String() + "\n")
+		handleErr(cli, err, 1)
+		
+	case bumpCli:
+		// Re-generate the UUID of a module
+		if len(cli.Args) != 1 {
+			cli.Errorln("please specify one module directory")
+			cli.Usage()
+			os.Exit(2)
+		}
+		
+		dir := cli.Args[0]
+		metadataPath := filepath.Join(dir, "fspl.mod")
+		file, err := os.OpenFile(metadataPath, os.O_RDWR, 0644)
+		handleErr(cli, err, 1)
+		defer file.Close()
+
+		lx, err := lexer.LexReader(metadataPath, file)
+		handleErr(cli, err, 1)
+		meta := metaParser.Tree { }
+		err = meta.Parse(lx)
+		handleErr(cli, err, 1)
+		
+		newModuleId, err := uuid.NewRandom()
+		handleErr(cli, err, 1)
+		cli.Println("changing uuid of", dir + ":", meta.UUID, "->", newModuleId)
+		meta.UUID = newModuleId
+		
+		file.Truncate(0)
+		file.Seek(0, 0)
+		_, err = io.WriteString(file, meta.String() + "\n")
+		handleErr(cli, err, 1)
+
+	default:
+		applicationCli.Usage()
+		os.Exit(2)
+	}
+}