Add support for terraform registry submodules

Fixes #1

README.md

@@ -48,6 +48,12 @@ module "vpc" {
   source  = "terraform-aws-modules/vpc/aws"
   version = "5.0.0"
 }
+
+# Submodules
+module "" {
+  source  = "terraform-aws-modules/iam/aws//modules/iam-assumable-role"
+  version = "5.33.1"
+}
 ```
 
 #### [Github](https://developer.hashicorp.com/terraform/language/modules/sources#github)

src/terraform/module.ts

@@ -69,9 +69,20 @@ const getTerraformRegistryUri: (moduleSource: string) => vscode.Uri | undefined
   }
 
   // Public Registry
-  if (moduleSource.split("/").length === 3) {
-    // <hostname>/<namespace>/<name>
-    return vscode.Uri.parse(`https://registry.terraform.io/modules/${moduleSource}`);
+  const baseUrl = 'https://registry.terraform.io/modules';
+  const [namespace, name, provider, ...submodules] = moduleSource.split("/").filter(part => part !== '');
+
+  // Submodule
+  // <hostname>/<namespace>/<name>/<provider>/<submodule>
+  if (submodules.length > 0) {
+    const submodulePath = `/submodules/${submodules.join("/").replace("modules/", "")}`;
+    return vscode.Uri.parse(`${baseUrl}/${namespace}/${name}/${provider}/latest${submodulePath}`);
+  }
+
+  // Module
+  // <hostname>/<namespace>/<name>
+  if (namespace && name && provider) {
+    return vscode.Uri.parse(`${baseUrl}/${moduleSource}`);
   }
 
   return;

src/test/suite/extension.test.ts

@@ -25,6 +25,10 @@ suite('Extension Test Suite', () => {
 				input: "terraform-aws-modules/vpc/aws",
 				expected: "https://registry.terraform.io/modules/terraform-aws-modules/vpc/aws"
 			},
+			{
+				input: "terraform-aws-modules/iam/aws//modules/iam-assumable-role",
+				expected: "https://registry.terraform.io/modules/terraform-aws-modules/iam/aws/latest/submodules/iam-assumable-role"
+			},
 			{
 				input: "github.com/hashicorp/example",
 				expected: "https://github.com/hashicorp/example/tree/HEAD/"