feat: Terraform version detected from project config

old projects are backward compatible

.gitignore

@@ -1,6 +1,7 @@
 .idea
 src/build/
+src/build*/
 config.tf
 environment.tf
 .env
-bin
+bin

src/command_backend.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"gopkg.in/alecthomas/kingpin.v2"
 	"path/filepath"
+	"strconv"
 	"strings"
 	"text/template"
 )
@@ -36,6 +37,7 @@ type BackendConfig struct {
 	TerraformStateKey    string
 	TerraformLockTable   string
 	KmsKeyArn            string
+	TerraformVersion     int
 }
 
 type dotEnv struct {
@@ -161,6 +163,10 @@ func (c *BackendCommand) applyInvoker(config *BackendConfig) {
 		c.log.ShowOpts("Invoker", "enabled")
 		config.TerraformStateKey = strings.Join([]string{config.TerraformStateKey, defaultTerraformInvokerSuffix}, "-")
 	}
+
+	if config.TerraformVersion >= 2 {
+		config.TerraformStateKey = config.TerraformStateKey + "/v" + strconv.Itoa(config.TerraformVersion)
+	}
 }
 
 func (c *BackendCommand) dotEnvMapper(env *dotEnv) *BackendConfig {
@@ -172,6 +178,7 @@ func (c *BackendCommand) dotEnvMapper(env *dotEnv) *BackendConfig {
 		KmsKeyArn:            env.environment["KMS_KEY_ARN"],
 		TerraformStateKey:    env.project["TERRAFORM_STATE_KEY"],
 		Domain:               env.project["DOMAIN"],
+		TerraformVersion:     c.app.IntResolver(env.project["TERRAFORM_VERSION"]),
 	}
 }
 

src/main.go

@@ -1,6 +1,6 @@
 package main
 
-const Version = "v0.5.0"
+const Version = "v0.5.1"
 
 const CiEnvVar = "CI"
 const EnvVersionVar = "TF_ENV_VERSION"

src/utils.go

@@ -5,6 +5,7 @@ import (
 	"github.com/joho/godotenv"
 	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 	"text/template"
 )
@@ -125,6 +126,14 @@ func (a *App) BoolResolver(text string) bool {
 	return false
 }
 
+func (a *App) IntResolver(text string) int {
+	if strings.EqualFold(text, "") || strings.EqualFold(text, "1") {
+		return 1
+	}
+	intVar, _ := strconv.Atoi(text)
+	return intVar
+}
+
 func (a *App) isNewEnvVersion() bool {
 	if strings.EqualFold(a.envVersion, "2") {
 		return true