New feature to specify custome location

lib/install.go

@@ -8,6 +8,7 @@ import (
 	"regexp"
 	"runtime"
 
+	"github.com/warrensbox/terraform-switcher/lib"
 	"github.com/warrensbox/tgswitch/modal"
 )
 
@@ -47,17 +48,34 @@ func init() {
 	for path := next(); len(path) > 0; path = next() {
 		installedBinPath = path
 	}
+
+	/* remove current symlink if exist*/
+	symlinkExist := CheckSymlink(installedBinPath)
+
+	if symlinkExist {
+		RemoveSymlink(installedBinPath)
+	}
 	/* Create local installation directory if it does not exist */
 	CreateDirIfNotExist(installLocation)
 }
 
 //Install : Install the provided version in the argument
-func Install(url string, appversion string, assests []modal.Repo, userBinPath * string) string {
+func Install(url string, appversion string, assests []modal.Repo, userBinPath *string) string {
+
 	/* If user provided bin path use user one instead of default */
 	if userBinPath != nil {
 		installedBinPath = *userBinPath
 	}
 
+	pathDir := lib.Path(installedBinPath)     //get path directory from binary path
+	binDirExist := lib.CheckDirExist(pathDir) //check bin path exist
+
+	if !binDirExist {
+		fmt.Printf("Binary path does not exist: %s\n", pathDir)
+		fmt.Printf("Please create binary path: %s for terragrunt installation\n", pathDir)
+		os.Exit(1)
+	}
+
 	/* check if selected version already downloaded */
 	fileExist := CheckFileExist(installLocation + installVersion + appversion)
 
@@ -195,3 +213,20 @@ func GetRecentVersions() ([]string, error) {
 func CreateRecentFile(requestedVersion string) {
 	WriteLines([]string{requestedVersion}, installLocation+recentFile)
 }
+
+// ValidVersionFormat : returns valid version format
+/* For example: 0.1.2 = valid
+// For example: 0.1.2-beta1 = valid
+// For example: 0.1.2-alpha = valid
+// For example: a.1.2 = invalid
+// For example: 0.1. 2 = invalid
+*/
+func ValidVersionFormat(version string) bool {
+
+	// Getting versions from body; should return match /X.X.X-@/ where X is a number,@ is a word character between a-z or A-Z
+	// Follow https://semver.org/spec/v1.0.0-beta.html
+	// Check regular expression at https://rubular.com/r/ju3PxbaSBALpJB
+	semverRegex := regexp.MustCompile(`^(\d+\.\d+\.\d+)(-[a-zA-z]+\d*)?$`)
+
+	return semverRegex.MatchString(version)
+}

lib/list_versions_test.go

@@ -24,3 +24,100 @@ func TestRemoveDuplicateVersions(t *testing.T) {
 		t.Log("Write versions exist (expected)")
 	}
 }
+
+//TestValidVersionFormat : test if func returns valid version format
+// more regex testing at https://rubular.com/r/UvWXui7EU2icSb
+func TestValidVersionFormat(t *testing.T) {
+
+	var version string
+	version = "0.11.8"
+
+	valid := lib.ValidVersionFormat(version)
+
+	if valid == true {
+		t.Logf("Valid version format : %s (expected)", version)
+	} else {
+		log.Fatalf("Failed to verify version format: %s\n", version)
+	}
+
+	version = "1.11.9"
+
+	valid = lib.ValidVersionFormat(version)
+
+	if valid == true {
+		t.Logf("Valid version format : %s (expected)", version)
+	} else {
+		log.Fatalf("Failed to verify version format: %s\n", version)
+	}
+
+	version = "1.11.a"
+
+	valid = lib.ValidVersionFormat(version)
+
+	if valid == false {
+		t.Logf("Invalid version format : %s (expected)", version)
+	} else {
+		log.Fatalf("Failed to verify version format: %s\n", version)
+	}
+
+	version = "22323"
+
+	valid = lib.ValidVersionFormat(version)
+
+	if valid == false {
+		t.Logf("Invalid version format : %s (expected)", version)
+	} else {
+		log.Fatalf("Failed to verify version format: %s\n", version)
+	}
+
+	version = "@^&*!)!"
+
+	valid = lib.ValidVersionFormat(version)
+
+	if valid == false {
+		t.Logf("Invalid version format : %s (expected)", version)
+	} else {
+		log.Fatalf("Failed to verify version format: %s\n", version)
+	}
+
+	version = "1.11.9-beta1"
+
+	valid = lib.ValidVersionFormat(version)
+
+	if valid == true {
+		t.Logf("Valid version format : %s (expected)", version)
+	} else {
+		log.Fatalf("Failed to verify version format: %s\n", version)
+	}
+
+	version = "0.12.0-rc2"
+
+	valid = lib.ValidVersionFormat(version)
+
+	if valid == true {
+		t.Logf("Valid version format : %s (expected)", version)
+	} else {
+		log.Fatalf("Failed to verify version format: %s\n", version)
+	}
+
+	version = "1.11.4-boom"
+
+	valid = lib.ValidVersionFormat(version)
+
+	if valid == true {
+		t.Logf("Valid version format : %s (expected)", version)
+	} else {
+		log.Fatalf("Failed to verify version format: %s\n", version)
+	}
+
+	version = "1.11.4-1"
+
+	valid = lib.ValidVersionFormat(version)
+
+	if valid == false {
+		t.Logf("Invalid version format : %s (expected)", version)
+	} else {
+		log.Fatalf("Failed to verify version format: %s\n", version)
+	}
+
+}

lib/symlink.go

@@ -1,19 +1,24 @@
 package lib
 
 import (
-	"fmt"
 	"log"
 	"os"
 )
 
+//CreateSymlink : create symlink
 //CreateSymlink : create symlink
 func CreateSymlink(cwd string, dir string) {
 
 	err := os.Symlink(cwd, dir)
 	if err != nil {
-		fmt.Println(err)
-		log.Fatalf("Unable to create symlink. You must have SUDO privileges %v \n", err)
-		panic(err)
+		log.Fatalf(`
+		Unable to create new symlink.
+		Maybe symlink already exist. Try removing existing symlink manually.
+		Try running "unlink" to remove existing symlink.
+		If error persist, you may not have the permission to create a symlink at %s.
+		Error: %s
+		`, dir, dir, err)
+		os.Exit(1)
 	}
 }
 
@@ -22,34 +27,38 @@ func RemoveSymlink(symlinkPath string) {
 
 	_, err := os.Lstat(symlinkPath)
 	if err != nil {
-		fmt.Println(err)
-		log.Fatalf("Unable to find symlink. You must have SUDO privileges - %v \n", err)
-		panic(err)
+		log.Fatalf(`
+		Unable to remove symlink.
+		Maybe symlink already exist. Try removing existing symlink manually.
+		Try running "unlink" to remove existing symlink.
+		If error persist, you may not have the permission to create a symlink at %s.
+		Error: %s
+		`, symlinkPath, symlinkPath, err)
+		os.Exit(1)
 	} else {
 		errRemove := os.Remove(symlinkPath)
 		if errRemove != nil {
-			fmt.Println(errRemove)
-			log.Fatalf("Unable to remove symlink. You must have SUDO privileges - %v \n", errRemove)
-			panic(errRemove)
+			log.Fatalf(`
+			Unable to remove symlink.
+			Maybe symlink already exist. Try removing existing symlink manually.
+			Try running "unlink" to remove existing symlink.
+			If error persist, you may not have the permission to create a symlink at %s.
+			Error: %s
+			`, symlinkPath, symlinkPath, errRemove)
+			os.Exit(1)
 		}
 	}
 }
 
 // CheckSymlink : check file is symlink
 func CheckSymlink(symlinkPath string) bool {
 
-	//symlink := false
-	//fmt.Println("Checking symlink")
-
 	fi, err := os.Lstat(symlinkPath)
 	if err != nil {
-		fmt.Println(err)
-		// symlink = false
 		return false
 	}
 
 	if fi.Mode()&os.ModeSymlink != 0 {
-		//symlink = true
 		return true
 	}
 

main.go

@@ -17,9 +17,11 @@ package main
 
 import (
 	"fmt"
+	"io/ioutil"
 	"log"
 	"os"
 	"regexp"
+	"strings"
 
 	"github.com/manifoldco/promptui"
 	"github.com/pborman/getopt"
@@ -29,9 +31,11 @@ import (
 
 const (
 	terragruntURL = "https://api.github.com/repos/gruntwork-io/terragrunt/releases?"
+	defaultBin    = "/usr/local/bin/terragrunt" //default bin installation dir
+	rcFilename    = ".tgswitchrc"
 )
 
-var version = "0.1.0\n"
+var version = "0.2.0\n"
 
 var CLIENT_ID = "xxx"
 var CLIENT_SECRET = "xxx"
@@ -43,21 +47,47 @@ func main() {
 	client.ClientID = CLIENT_ID
 	client.ClientSecret = CLIENT_SECRET
 
-	userBinPath := getopt.StringLong("bin", 'b', "Custom binary path. For example: /Users/username/bin/terragrunt")
+	custBinPath := getopt.StringLong("bin", 'b', defaultBin, "Custom binary path. For example: /Users/username/bin/terragrunt")
 	versionFlag := getopt.BoolLong("version", 'v', "displays the version of tgswitch")
 	helpFlag := getopt.BoolLong("help", 'h', "displays help message")
 	_ = versionFlag
 
 	getopt.Parse()
 	args := getopt.Args()
 
+	dir, err := os.Getwd()
+	if err != nil {
+		log.Printf("Failed to get current directory %v\n", err)
+		os.Exit(1)
+	}
+
+	rcfile := dir + fmt.Sprintf("/%s", rcFilename) //settings for .tfswitchrc file in current directory
+
 	if *versionFlag {
 		fmt.Printf("\nVersion: %v\n", version)
 	} else if *helpFlag {
 		usageMessage()
 	} else {
 
-		if len(args) == 1 {
+		if _, err := os.Stat(rcfile); err == nil && len(args) == 0 { //if there is a .tfswitchrc file, and no commmand line arguments
+			fmt.Printf("Reading required terraform version %s \n", rcFilename)
+
+			fileContents, err := ioutil.ReadFile(rcfile)
+			if err != nil {
+				fmt.Printf("Failed to read %s file. Follow the README.md instructions for setup. https://github.com/warrensbox/terraform-switcher/blob/master/README.md\n", rcFilename)
+				fmt.Printf("Error: %s\n", err)
+				os.Exit(1)
+			}
+			tfversion := strings.TrimSuffix(string(fileContents), "\n")
+			_, assets := lib.GetAppList(terragruntURL, &client)
+
+			if lib.ValidVersionFormat(tfversion) { //check if version is correct
+				lib.Install(terragruntURL, string(tfversion), assets, custBinPath)
+			} else {
+				fmt.Println("Invalid terraform version format. Format should be #.#.# or #.#.#-@# where # is numbers and @ is word characters. For example, 0.11.7 and 0.11.9-beta1 are valid versions")
+				os.Exit(1)
+			}
+		} else if len(args) == 1 {
 
 			semverRegex := regexp.MustCompile(`\A\d+(\.\d+){2}\z`)
 			if semverRegex.MatchString(args[0]) {
@@ -68,7 +98,7 @@ func main() {
 				exist := lib.VersionExist(requestedVersion, tflist)
 
 				if exist {
-					installLocation := lib.Install(terragruntURL, requestedVersion, assets, userBinPath)
+					installLocation := lib.Install(terragruntURL, requestedVersion, assets, custBinPath)
 					lib.AddRecent(requestedVersion, installLocation) //add to recent file for faster lookup
 				} else {
 					fmt.Println("Not a valid terragrunt version")
@@ -100,7 +130,7 @@ func main() {
 				os.Exit(1)
 			}
 
-			installLocation := lib.Install(terragruntURL, tgversion, assets, userBinPath)
+			installLocation := lib.Install(terragruntURL, tgversion, assets, custBinPath)
 			lib.AddRecent(tgversion, installLocation) //add to recent file for faster lookup
 			os.Exit(0)
 		} else {