Very basic module installation flag added

main.go

@@ -280,6 +280,7 @@ func main() {
 	verFlag := flag.Bool("v", false, "Print version information and exit")
 	runCommand := flag.String("run", "", "A quoted string of commands to run and get output from")
 	preloadEnv := flag.Bool("L", false, "Preload all files in the slope preload directory")
+	moduleInstall := flag.String("install", "", "URL to a module's git repo")
 	flag.Parse()
 	args := flag.Args()
 
@@ -288,8 +289,12 @@ func main() {
 		os.Exit(0)
 	}
 
-	Init()
+	if *moduleInstall != "" {
+		InstallModule(*moduleInstall)
+		os.Exit(0)
+	}
 
+	Init()
 
 	if *runCommand != "" {
 		if *preloadEnv {

mod-manager.go

@@ -0,0 +1,78 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"path"
+	"path/filepath"
+	"strings"
+)
+
+func ModName(url, modDir string) string {
+	base := path.Base(url)
+	if strings.HasSuffix(base, ".git") {
+		base = base[:len(base)-4]
+	}
+
+	_, err := os.Stat(filepath.Join(modDir, base))
+	if err != nil && base != "" {
+		return base
+	}
+	modbase := base
+	var agreement string
+	for {
+		fmt.Printf("---> The module %q already exists.\n---> Enter an alternate import name to use or ^C to cancel: ", modbase)
+		fmt.Scanln(&base)
+		fmt.Printf("-> Are you happy with %q?\n-> Type 'yes' to proceed: ", base)
+		fmt.Scanln(&agreement)
+		if strings.ToLower(agreement) == "yes" {
+			break
+		}
+	}
+	return base
+}
+
+func Clone(url, modDir string) (string, error) {
+	pwd, err := os.Getwd()
+	if err != nil {
+		return "", fmt.Errorf("Unable to get current working directory\n")
+	}
+	defer func(){os.Chdir(pwd)}()
+	err = os.Chdir(modDir)
+	if err != nil && os.IsNotExist(err) {
+		createDataDirs(modDir)
+		err := os.Chdir(modDir)
+		if err != nil {
+			return "", fmt.Errorf("Unable to navigate to module directory: %s \n", modDir)
+		}
+	} else if err != nil {
+		return "", fmt.Errorf("Unable to navigate to module directory: %s\n", modDir)
+	}
+
+	moduleName := ModName(url, modDir)
+	fmt.Printf("Cloning %q...\n", moduleName)
+	cmd := exec.Command("git", "clone", url, moduleName)
+	err = cmd.Run()
+	if err != nil {
+		return "", err
+	}
+	return filepath.Join(modDir, moduleName), nil
+}
+
+func InstallModule(url string) {
+	fmt.Println("NOTE: Submodules and module dependencies are not yet supported and will need to be acquired manually by a separate module installation")
+	modDir := getModBaseDir()
+	p, err := Clone(url, modDir)
+	if err != nil || p == "" {
+		fmt.Fprintf(os.Stderr, err.Error())
+		return
+	}
+	_, err = os.Stat(filepath.Join(p, "main.slo"))
+	if err != nil && os.IsNotExist(err) {
+		fmt.Fprintf(os.Stderr, "Invalid module, no 'main.slo' file. Removing from module folder\n")
+		_ = os.RemoveAll(p)
+		return
+	}
+	fmt.Println("Module successfully installed")
+}