feat: use file watchers to track some setup statuses

Setup statuses for LS CLI authentication and AWS profile configuration are now checked via file watchers instead of periodic checks.
feat: use file watchers to track the LS CLI status

License status for LS CLI is now checked via file watchers instead of periodic checks.
WIP Assignments
perf
rename
lint

Author: skyrpex

package-lock.json

@@ -111,7 +111,8 @@
 		"package": "node build/extension.mjs --production",
 		"pretest": "npm run compile",
 		"check-types": "tsc",
-		"lint": "eslint .",
+		"lint": "eslint",
+		"format": "biome check",
 		"test": "vscode-test",
 		"compile:font": "node build/icon-font.mjs"
 	},
@@ -127,6 +128,7 @@
 		"@vscode/test-cli": "^0.0.11",
 		"@vscode/test-electron": "^2.5.2",
 		"@vscode/vsce": "^3.6.0",
+		"chokidar": "^4.0.3",
 		"esbuild": "^0.25.9",
 		"eslint": "^9.35.0",
 		"eslint-plugin-import": "^2.32.0",

package.json

@@ -84,7 +84,7 @@ async function redirectToLocalStack(): Promise<{ cancelled: boolean }> {
 	return { cancelled: !openSuccessful };
 }
 
-const LOCALSTACK_AUTH_FILENAME = `${os.homedir()}/.localstack/auth.json`;
+export const LOCALSTACK_AUTH_FILENAME = `${os.homedir()}/.localstack/auth.json`;
 const LOCALSTACK_AUTH_FILENAME_READABLE = LOCALSTACK_AUTH_FILENAME.replace(
 	`${os.homedir()}/`,
 	"~/",

src/utils/authenticate.ts

@@ -35,7 +35,9 @@ const LOCALSTACK_CREDENTIALS_PROPERTIES = {
 	aws_secret_access_key: "test",
 };
 
-const AWS_DIRECTORY = path.join(os.homedir(), ".aws");
+export const AWS_DIRECTORY = path.join(os.homedir(), ".aws");
+export const AWS_CONFIG_FILENAME = path.join(AWS_DIRECTORY, "config");
+export const AWS_CREDENTIALS_FILENAME = path.join(AWS_DIRECTORY, "credentials");
 
 async function overrideSelection(
 	filesToModify: string[],
@@ -464,13 +466,13 @@ export async function configureAwsProfiles(options: {
 
 export async function checkIsProfileConfigured(): Promise<boolean> {
 	try {
-		const awsConfigFilename = path.join(AWS_DIRECTORY, "config");
-		const awsCredentialsFilename = path.join(AWS_DIRECTORY, "credentials");
-
 		const [{ section: configSection }, { section: credentialsSection }] =
 			await Promise.all([
-				getProfile(awsConfigFilename, LOCALSTACK_CONFIG_PROFILE_NAME),
-				getProfile(awsCredentialsFilename, LOCALSTACK_CREDENTIALS_PROFILE_NAME),
+				getProfile(AWS_CONFIG_FILENAME, LOCALSTACK_CONFIG_PROFILE_NAME),
+				getProfile(
+					AWS_CREDENTIALS_FILENAME,
+					LOCALSTACK_CREDENTIALS_PROFILE_NAME,
+				),
 			]);
 
 		const [configNeedsOverride, credentialsNeedsOverride] = await Promise.all([

src/utils/configure-aws.ts

@@ -0,0 +1,23 @@
+/**
+ * Creates a function that calls the given callback immediately once.
+ *
+ * Multiple calls during the same tick are ignored.
+ *
+ * @param callback - The callback to call.
+ * @returns A function that calls the callback immediately once.
+ */
+export function immediateOnce<T>(callback: () => T): () => void {
+	let timeout: NodeJS.Immediate | undefined;
+
+	return () => {
+		if (timeout) {
+			return;
+		}
+
+		timeout = setImmediate(() => {
+			void Promise.resolve(callback()).finally(() => {
+				timeout = undefined;
+			});
+		});
+	};
+}

src/utils/immediate-once.ts

@@ -1,7 +1,36 @@
+import { homedir, platform } from "node:os";
+import { join } from "node:path";
+
 import type { CancellationToken, LogOutputChannel } from "vscode";
 
 import { execLocalStack } from "./cli.ts";
 
+/**
+ * See https://github.com/localstack/localstack/blob/de861e1f656a52eaa090b061bd44fc1a7069715e/localstack-core/localstack/utils/files.py#L38-L55.
+ * @returns The cache directory for the current platform.
+ */
+const cacheDirectory = () => {
+	switch (platform()) {
+		case "win32":
+			return join(process.env.LOCALAPPDATA!, "cache");
+		case "darwin":
+			return join(homedir(), "Library", "Caches");
+		default:
+			return process.env.XDG_CACHE_HOME ?? join(homedir(), ".cache");
+	}
+};
+
+/**
+ * The file that contains the license information of the LocalStack CLI.
+ *
+ * The license file is stored in the cache directory for the current platform.
+ */
+export const LICENSE_FILENAME = join(
+	cacheDirectory(),
+	"localstack-cli",
+	"license.json",
+);
+
 const LICENSE_VALIDITY_MARKER = "license validity: valid";
 
 export async function checkIsLicenseValid(outputChannel: LogOutputChannel) {