feat(cli): throw an error if a user tries to create a new project with TFC on an old TF version

CHANGELOG.md

@@ -10,6 +10,8 @@ A very minor change in the interface names for provisioners occured [to support
 - `ILocalExecProvisioner` to `LocalExecProvisioner`
 - `IRemoteExecProvisioner` to `RemoteExecProvisioner`
 
+Another very minor change is that we now use the `CloudBackend` by default when running cdktf init. This requires Terraform >=1.1, therefore an error is thrown on `cdktf init` if you want to use Terraform Cloud and are on an older version. Already existing projects are not affected and you can use `cdktf init --local` and configure the `RemoteBackend` if you need to use an older version.
+
 ### fix
 
 - fix(hcl2json): add fs-extra to dependencies [\#2040](https://github.com/hashicorp/terraform-cdk/pull/2040)

packages/cdktf-cli/bin/cmds/helper/init.ts

@@ -32,6 +32,8 @@ import { init, Project } from "../../../lib";
 import { askForCrashReportingConsent } from "../../../lib/error-reporting";
 import ciDetect from "@npmcli/ci-detect";
 import { isInteractiveTerminal } from "./check-environment";
+import { getTerraformVersion } from "./terraform-check";
+import * as semver from "semver";
 
 const chalkColour = new chalk.Instance();
 
@@ -77,13 +79,21 @@ export async function runInit(argv: Options) {
     console.log(chalkColour`{yellow Note: By supplying '--local' option you have chosen local storage mode for storing the state of your stack.
 This means that your Terraform state file will be stored locally on disk in a file 'terraform.<STACK NAME>.tfstate' in the root of your project.}`);
   }
+  const isRemote = token != "";
 
   // Check if template was specified by the user
   let template = "";
   if (argv.template) {
     template = argv.template;
   }
 
+  const tfVersion = await getTerraformVersion();
+  if (tfVersion && semver.lt(tfVersion, "1.1.0") && isRemote) {
+    throw Errors.Usage(
+      `Terraform version ${tfVersion} is not supported for remote configuration. We use the CloudBackend to configure the connection to Terraform Cloud, which is only supported in Terraform 1.1 and higher. Please upgrade to version 1.1.0 or higher or use the local mode by passing --local (afterwards you can use the RemoteBackend to work with Terraform Cloud without upgrading your Terraform version.`
+    );
+  }
+
   // Gather information about the template and the project
   const templateInfo = await getTemplate(template);
   telemetryData.template = templateInfo.Name;
@@ -111,9 +121,8 @@ This means that your Terraform state file will be stored locally on disk in a fi
       throw new Error(`Missing organization name in project info`);
     }
 
-    // Check if token is set so we can set up Terraform Cloud workspace
-    // only set with the '--local' option is specified the user.
-    if (token != "") {
+    // Set up a Terraform Cloud workspace if the user opted-in
+    if (isRemote) {
       telemetryData.isRemote = Boolean(token);
       console.log(
         chalkColour`\n{whiteBright Setting up remote state backend and workspace in Terraform Cloud.}`

packages/cdktf-cli/bin/cmds/helper/terraform-check.ts

@@ -4,19 +4,13 @@ import { SynthesizedStack } from "../../../lib/synth-stack";
 import { existsSync } from "fs-extra";
 import * as path from "path";
 import { AbortController } from "node-abort-controller"; // polyfill until we update to node 14
+import { logger } from "../../../lib/logging";
 
-const MIN_SUPPORTED_VERSION = "0.13.0";
+const MIN_SUPPORTED_VERSION = "1.0.0";
 const VERSION_REGEXP = /Terraform v\d+.\d+.\d+/;
 
-export const terraformCheck = async (): Promise<void> => {
+export const getTerraformVersion = async (): Promise<string | null> => {
   try {
-    if (existsSync(path.join(process.cwd(), "terraform.tfstate"))) {
-      throw new Error(`
-        CDK for Terraform now supports multiple stacks!
-        Found 'terraform.tfstate' Terraform state file. Please rename it to match the stack name. Learn more https://cdk.tf/multiple-stacks
-      `);
-    }
-
     // We're abusing the TerraformCli class here,
     // hence we need to construct this object.
     // Only the `workingDirectory` is releveant here.
@@ -35,14 +29,32 @@ export const terraformCheck = async (): Promise<void> => {
     const terraformVersion = await terraform.version();
     const terraformVersionMatches = terraformVersion.match(VERSION_REGEXP);
 
-    if (terraformVersionMatches !== null) {
-      // Should always be the first match found in the string
-      const cleanTerraformVersion = semver.clean(
-        terraformVersionMatches[0].substring(
-          terraformVersionMatches[0].indexOf("v")
-        )
-      );
+    if (terraformVersionMatches === null) {
+      return null;
+    }
+    // Should always be the first match found in the string
+    return semver.clean(
+      terraformVersionMatches[0].substring(
+        terraformVersionMatches[0].indexOf("v")
+      )
+    );
+  } catch (e) {
+    logger.info(`Unable to determine Terraform version: ${e}`);
+    return null;
+  }
+};
+
+export const terraformCheck = async (): Promise<void> => {
+  try {
+    if (existsSync(path.join(process.cwd(), "terraform.tfstate"))) {
+      throw new Error(`
+        CDK for Terraform now supports multiple stacks!
+        Found 'terraform.tfstate' Terraform state file. Please rename it to match the stack name. Learn more https://cdk.tf/multiple-stacks
+      `);
+    }
+    const cleanTerraformVersion = await getTerraformVersion();
 
+    if (cleanTerraformVersion !== null) {
       if (
         cleanTerraformVersion &&
         semver.lt(cleanTerraformVersion, MIN_SUPPORTED_VERSION)