feat!: Initial v2 commit

* Implemented editorconfig
* Switched to ESM
* Switched to a TypeScript workflow
* Switched to projen for project management
* Major code refactor
* TODO: need tests

src/helpers.ts

@@ -0,0 +1,67 @@
+import { STSClient } from '@aws-sdk/client-sts';
+
+const MAX_TAG_VALUE_LENGTH = 256;
+const SANITIZATION_CHARACTER = '_';
+
+let stsclient: STSClient | undefined;
+
+export function getStsClient(region: string, agent?: string) {
+  if (!stsclient) {
+    stsclient = new STSClient({
+      region,
+      customUserAgent: agent,
+    });
+  }
+  return stsclient;
+}
+
+export function sanitizeGithubActor(actor: string) {
+  // In some circumstances the actor may contain square brackets. For example, if they're a bot ('[bot]')
+  // Square brackets are not allowed in AWS session tags
+  return actor.replace(/\[|\]/g, SANITIZATION_CHARACTER);
+}
+
+export function sanitizeGithubWorkflowName(name: string) {
+  // Workflow names can be almost any valid UTF-8 string, but tags are more restrictive.
+  // This replaces anything not conforming to the tag restrictions by inverting the regular expression.
+  // See the AWS documentation for constraint specifics https://docs.aws.amazon.com/STS/latest/APIReference/API_Tag.html.
+  const nameWithoutSpecialCharacters = name.replace(/[^\p{L}\p{Z}\p{N}_:/=+.-@-]/gu, SANITIZATION_CHARACTER);
+  const nameTruncated = nameWithoutSpecialCharacters.slice(0, MAX_TAG_VALUE_LENGTH);
+  return nameTruncated;
+}
+
+export function errorMessage(error: unknown) {
+  return error instanceof Error ? error.message : String(error);
+}
+
+export function isDefined<T>(i: T | undefined | null): i is T {
+  return i !== undefined && i !== null;
+}
+
+function sleep(ms: number) {
+  return new Promise((resolve) => setTimeout(resolve, ms));
+}
+
+// retryAndBackoff retries with exponential backoff the promise if the error isRetryable upto maxRetries time.
+export async function retryAndBackoff<T>(
+  fn: () => Promise<T>,
+  isRetryable: boolean,
+  retries = 0,
+  maxRetries = 12,
+  base = 50
+): Promise<T> {
+  try {
+    return await fn();
+  } catch (err) {
+    if (!isRetryable) {
+      throw err;
+    }
+    // It's retryable, so sleep and retry.
+    await sleep(Math.random() * (Math.pow(2, retries) * base));
+    retries += 1;
+    if (retries === maxRetries) {
+      throw err;
+    }
+    return await retryAndBackoff(fn, isRetryable, retries, maxRetries, base);
+  }
+}