added test files

Makefile

@@ -21,8 +21,10 @@ clean:
 
 .PHONY: test
 test: $(EXE)
+	mkdir -p build
 	mv $(EXE) build
 	go test -v ./...
+	find ./test-data/* -type d -print0 | while read -r -d $'\0' TEST_PATH; do ./build/tgswitch -c "${TEST_PATH}" || exit 1; done;
 
 .PHONY: install
 install: $(EXE)

go.mod

@@ -3,6 +3,7 @@ module github.com/warrensbox/tgswitch
 go 1.16
 
 require (
+	github.com/hashicorp/go-version v1.5.0 // indirect
 	github.com/hashicorp/hcl2 v0.0.0-20191002203319-fb75b3253c80 // indirect
 	github.com/manifoldco/promptui v0.9.0
 	github.com/mitchellh/go-homedir v1.1.0 // indirect

go.sum

@@ -241,6 +241,8 @@ github.com/hashicorp/go-sockaddr v1.0.0/go.mod h1:7Xibr9yA9JjQq1JpNB2Vw7kxv8xerX
 github.com/hashicorp/go-syslog v1.0.0/go.mod h1:qPfqrKkXGihmCqbJM2mZgkZGvKG1dFdvsLplgctolz4=
 github.com/hashicorp/go-uuid v1.0.0/go.mod h1:6SBZvOh/SIDV7/2o3Jml5SYk/TvGqwFJ/bN7x4byOro=
 github.com/hashicorp/go-uuid v1.0.1/go.mod h1:6SBZvOh/SIDV7/2o3Jml5SYk/TvGqwFJ/bN7x4byOro=
+github.com/hashicorp/go-version v1.5.0 h1:O293SZ2Eg+AAYijkVK3jR786Am1bhDEh2GHT0tIVE5E=
+github.com/hashicorp/go-version v1.5.0/go.mod h1:fltr4n8CU8Ke44wwGCBoEymUuxUHl09ZGVZPK5anwXA=
 github.com/hashicorp/golang-lru v0.5.0/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
 github.com/hashicorp/golang-lru v0.5.1/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
 github.com/hashicorp/golang-lru v0.5.4/go.mod h1:iADmTwqILo4mZ8BN3D2Q6+9jd8WM5uGBxy+E8yxSoD4=

lib/install.go

@@ -171,6 +171,9 @@ func ValidVersionFormat(version string) bool {
 //Install : Install the provided version in the argument
 func Install(tgversion string, usrBinPath string, mirrorURL string) string {
 
+	println("tgversion", tgversion)
+	println("usrBinPath", usrBinPath)
+	println("mirrorURL", mirrorURL)
 	/* Check to see if user has permission to the default bin location which is  "/usr/local/bin/terragrunt"
 	 * If user does not have permission to default bin location, proceed to create $HOME/bin and install the tfswitch there
 	 * Inform user that they dont have permission to default location, therefore tfswitch was installed in $HOME/bin
@@ -184,13 +187,25 @@ func Install(tgversion string, usrBinPath string, mirrorURL string) string {
 	goarch := runtime.GOARCH
 	goos := runtime.GOOS
 
-	installFileVersionPath := ConvertExecutableExt(filepath.Join(installLocation, installVersion+tgversion))
-
 	/* check if selected version already downloaded */
+	installFileVersionPath := ConvertExecutableExt(filepath.Join(installLocation, installVersion+tgversion))
 	fileExist := CheckFileExist(installLocation + installVersion + tgversion)
+
+	/* if selected version already exist, */
 	if fileExist {
-		installLocation := ChangeSymlink(binPath, tgversion)
-		return installLocation
+
+		/* remove current symlink if exist*/
+		symlinkExist := CheckSymlink(binPath)
+
+		if symlinkExist {
+			RemoveSymlink(binPath)
+		}
+
+		/* set symlink to desired version */
+		CreateSymlink(installFileVersionPath, binPath)
+		fmt.Printf("Switched terragrunt to version %q \n", tgversion)
+		AddRecent(tgversion) //add to recent file for faster lookup
+		os.Exit(0)
 	}
 
 	//if does not have slash - append slash

lib/list_versions.go

@@ -2,7 +2,6 @@ package lib
 
 import (
 	"encoding/json"
-	"fmt"
 	"io/ioutil"
 	"log"
 	"net/http"
@@ -27,10 +26,6 @@ func VersionExist(val interface{}, array interface{}) (exists bool) {
 		}
 	}
 
-	if !exists {
-		fmt.Println("Requested version does not exist")
-	}
-
 	return exists
 }
 

lib/semver.go

@@ -0,0 +1,55 @@
+package lib
+
+import (
+	"fmt"
+	"sort"
+
+	semver "github.com/hashicorp/go-version"
+)
+
+// GetSemver : returns version that will be installed based on server constaint provided
+func GetSemver(tgconstraint *string, proxyUrl string) (string, error) {
+
+	tglist := GetAppList(proxyUrl) //get list of versions
+	fmt.Printf("Reading required version from constraint: %s\n", *tgconstraint)
+	tfversion, err := SemVerParser(tgconstraint, tglist)
+	return tfversion, err
+}
+
+// ValidateSemVer : Goes through the list of terragrunt version, return a valid tf version for contraint provided
+func SemVerParser(tfconstraint *string, tflist []string) (string, error) {
+	tfversion := ""
+	constraints, err := semver.NewConstraint(*tfconstraint) //NewConstraint returns a Constraints instance that a Version instance can be checked against
+	if err != nil {
+		return "", fmt.Errorf("error parsing constraint: %s", err)
+	}
+	versions := make([]*semver.Version, len(tflist))
+	//put tfversion into semver object
+	for i, tfvals := range tflist {
+		version, err := semver.NewVersion(tfvals) //NewVersion parses a given version and returns an instance of Version or an error if unable to parse the version.
+		if err != nil {
+			return "", fmt.Errorf("error parsing constraint: %s", err)
+		}
+		versions[i] = version
+	}
+
+	sort.Sort(sort.Reverse(semver.Collection(versions)))
+
+	for _, element := range versions {
+		if constraints.Check(element) { // Validate a version against a constraint
+			tfversion = element.String()
+			fmt.Printf("Matched version: %s\n", tfversion)
+			if ValidVersionFormat(tfversion) { //check if version format is correct
+				return tfversion, nil
+			}
+		}
+	}
+
+	PrintInvalidTFVersion()
+	return "", fmt.Errorf("error parsing constraint: %s", *tfconstraint)
+}
+
+// Print invalid TF version
+func PrintInvalidTFVersion() {
+	fmt.Println("Version does not exist or invalid terraform version format.\n Format should be #.#.# or #.#.#-@# where # are numbers and @ are word characters.\n For example, 0.11.7 and 0.11.9-beta1 are valid versions")
+}

lib/symlink.go

@@ -1,22 +1,22 @@
 package lib
 
 import (
-	"fmt"
 	"log"
 	"os"
 )
 
 //CreateSymlink : create symlink
 //CreateSymlink : create symlink
 func CreateSymlink(cwd string, dir string) {
-
+	println("cwd", cwd)
+	println("dir", dir)
 	err := os.Symlink(cwd, dir)
 	if err != nil {
 		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.
+		If error persist, you may not have the permission to create a symlink at %s
 		Error: %s
 		`, dir, err)
 		os.Exit(1)
@@ -67,18 +67,17 @@ func CheckSymlink(symlinkPath string) bool {
 }
 
 // ChangeSymlink : move symlink to existing binary
-func ChangeSymlink(installedBinPath string, appversion string) string {
+func ChangeSymlink(binVersionPath string, binPath string) {
 
-	installLocation = GetInstallLocation() //get installation location -  this is where we will put our terragrunt binary file
+	binPath = InstallableBinLocation(binPath)
 
 	/* remove current symlink if exist*/
-	symlinkExist := CheckSymlink(installedBinPath)
+	symlinkExist := CheckSymlink(binPath)
 	if symlinkExist {
-		RemoveSymlink(installedBinPath)
+		RemoveSymlink(binPath)
 	}
+
 	/* set symlink to desired version */
-	CreateSymlink(installLocation+installVersion+appversion, installedBinPath)
-	fmt.Printf("Switched terragrunt to version %q \n", appversion)
-	return installLocation
+	CreateSymlink(binVersionPath, binPath)
 
 }

main.go

@@ -67,13 +67,20 @@ func main() {
 	TOMLConfigFile := filepath.Join(*chDirPath, tomlFilename)  //settings for .tgswitch.toml file in current directory (option to specify bin directory)
 	HomeTOMLConfigFile := filepath.Join(homedir, tomlFilename) //settings for .tgswitch.toml file in home directory (option to specify bin directory)
 	RCFile := filepath.Join(*chDirPath, rcFilename)            //settings for .tgswitchrc file in current directory (backward compatible purpose)
-	TFVersionFile := filepath.Join(*chDirPath, tgvFilename)    //settings for .terragrunt-version file in current directory (tfenv compatible)
+	TGVersionFile := filepath.Join(*chDirPath, tgvFilename)    //settings for .terragrunt-version file in current directory (tfenv compatible)
 	TGHACLFile := filepath.Join(*chDirPath, tgHclFilename)     //settings for terragrunt.hcl file in current directory
 	switch {
 	case *versionFlag:
 		fmt.Printf("\nVersion: %v\n", version)
 	case *helpFlag:
 		usageMessage()
+	/* Checks if the .tgswitch.toml file exist in home or current directory
+	 * This block checks to see if the tgswitch toml file is provided in the current path.
+	 * If the .tgswitch.toml file exist, it has a higher precedence than the .tgswitchrc file
+	 * You can specify the custom binary path and the version you desire
+	 * If you provide a custom binary path with the -b option, this will override the bin value in the toml file
+	 * If you provide a version on the command line, this will override the version value in the toml file
+	 */
 	case lib.FileExists(TOMLConfigFile) || lib.FileExists(HomeTOMLConfigFile):
 		version := ""
 		binPath := *custBinPath
@@ -82,7 +89,7 @@ func main() {
 		} else { // else read from toml from home directory
 			version, binPath = GetParamsTOML(binPath, homedir)
 		}
-		fmt.Println("version", version)
+
 		/* GIVEN A TOML FILE, */
 		switch {
 		case len(args) == 1:
@@ -111,20 +118,24 @@ func main() {
 		case lib.FileExists(RCFile) && len(args) == 0:
 			lib.ReadingFileMsg(rcFilename)
 			tgversion := lib.RetrieveFileContents(RCFile)
-			installVersion(tgversion, custBinPath)
+			installVersion(tgversion, &binPath)
 		/* if .terragrunt-version file found (IN ADDITION TO A TOML FILE) */
-		case lib.FileExists(TFVersionFile) && len(args) == 0:
-			lib.ReadingFileMsg(rcFilename)
-			tgversion := lib.RetrieveFileContents(RCFile)
-			installVersion(tgversion, custBinPath)
+		case lib.FileExists(TGVersionFile) && len(args) == 0:
+			lib.ReadingFileMsg(TGVersionFile)
+			tgversion := lib.RetrieveFileContents(TGVersionFile)
+			println("version", tgversion)
+			println("&binPath", string(binPath))
+			installVersion(tgversion, &binPath)
 		/* if Terraform Version environment variable is set  (IN ADDITION TO A TOML FILE)*/
 		case checkTGEnvExist() && len(args) == 0 && version == "":
-
+			tgversion := os.Getenv("TG_VERSION")
+			fmt.Printf("Terragrunt version environment variable: %s\n", tgversion)
+			installVersion(tgversion, &binPath)
 		/* if terragrunt.hcl file found (IN ADDITION TO A TOML FILE) */
 		case lib.FileExists(TGHACLFile) && checkVersionDefinedHCL(&TGHACLFile) && len(args) == 0:
-
+			installTGHclFile(&TGHACLFile, binPath, proxyUrl)
 		case version != "":
-			lib.Install(version, *custBinPath, terragruntURL)
+			lib.Install(version, binPath, terragruntURL)
 		default:
 			installFromList(&binPath)
 		}
@@ -153,10 +164,10 @@ func main() {
 				os.Exit(1)
 			}
 
-		} else if _, err := os.Stat(TFVersionFile); err == nil && len(args) == 0 {
+		} else if _, err := os.Stat(TGVersionFile); err == nil && len(args) == 0 {
 			fmt.Printf("Reading required terragrunt version %s \n", tgvFilename)
 
-			fileContents, err := ioutil.ReadFile(TFVersionFile)
+			fileContents, err := ioutil.ReadFile(TGVersionFile)
 			if err != nil {
 				fmt.Printf("Failed to read %s file. Follow the README.md instructions for setup. https://github.com/warrensbox/tgswitch/blob/master/README.md\n", tgvFilename)
 				fmt.Printf("Error: %s\n", err)
@@ -282,6 +293,8 @@ func installVersion(arg string, custBinPath *string) {
 		installFileVersionPath := lib.ConvertExecutableExt(filepath.Join(installLocation, versionPrefix+requestedVersion))
 		recentDownloadFile := lib.CheckFileExist(installFileVersionPath)
 		if recentDownloadFile {
+			println(string(*custBinPath))
+			println(installFileVersionPath)
 			lib.ChangeSymlink(installFileVersionPath, *custBinPath)
 			fmt.Printf("Switched terraform to version %q \n", requestedVersion)
 			lib.AddRecent(requestedVersion) //add to recent file for faster lookup
@@ -311,6 +324,32 @@ func checkTGEnvExist() bool {
 	return os.Getenv("TG_VERSION") != ""
 }
 
+// install using a version constraint
+func installFromConstraint(tgconstraint *string, custBinPath, mirrorURL string) {
+
+	tgversion, err := lib.GetSemver(tgconstraint, mirrorURL)
+	if err == nil {
+		lib.Install(tgversion, custBinPath, mirrorURL)
+	}
+	fmt.Println(err)
+	fmt.Println("No version found to match constraint. Follow the README.md instructions for setup. https://github.com/warrensbox/tgswitch/blob/master/README.md")
+	os.Exit(1)
+}
+
+// Install using version constraint from terragrunt file
+func installTGHclFile(tgFile *string, custBinPath, mirrorURL string) {
+	fmt.Printf("Terragrunt file found: %s\n", *tgFile)
+	parser := hclparse.NewParser()
+	file, diags := parser.ParseHCLFile(*tgFile) //use hcl parser to parse HCL file
+	if diags.HasErrors() {
+		fmt.Println("Unable to parse HCL file")
+		os.Exit(1)
+	}
+	var version terragruntVersionConstraints
+	gohcl.DecodeBody(file.Body, nil, &version)
+	installFromConstraint(&version.TerragruntVersionConstraint, custBinPath, mirrorURL)
+}
+
 // check if version is defined in hcl file /* lazy-emergency fix - will improve later */
 func checkVersionDefinedHCL(tgFile *string) bool {
 	parser := hclparse.NewParser()

test-data/test_terragrunt-version/.terragrunt-version

@@ -1 +1 @@
-0.34.5
+0.37.0

test-data/test_terragrunt_hcl/terragrunt.hcl

@@ -0,0 +1,16 @@
+include {
+  path = "${find_in_parent_folders()}"
+}
+
+terraform {
+  source = "..."
+
+  extra_arguments "variables" {
+    commands = get_terraform_commands_that_need_vars()
+  }
+}
+  inputs = merge(
+    jsondecode(file("${find_in_parent_folders("general.tfvars")}"))
+)
+
+terragrunt_version_constraint=">= 0.37, < 0.38"

test-data/test_tfswitchrc/.tgswitchrc

@@ -0,0 +1 @@
+0.37.2

test-data/test_tfswitchtoml/.tgswitch.toml

@@ -0,0 +1,2 @@
+bin = "/usr/local/bin/terragrunt"
+version = "0.37.3"

test-data/test_tgswitchrc/.tgswitchrc

@@ -1 +1 @@
-0.31.11
+0.37.4