feat: integrate XSLT Tools with toolbox portal

src/transform/transformLimits.ts

@@ -0,0 +1,65 @@
+import type { TransformRequest, TransformResult } from './transformTypes';
+
+export const TRANSFORM_LIMITS = {
+  maxXmlBytes: 5 * 1024 * 1024,
+  maxXsltBytes: 2 * 1024 * 1024,
+  maxOutputBytes: 10 * 1024 * 1024,
+  timeoutMs: 20_000,
+} as const;
+
+function utf8Bytes(value: string): number {
+  return new TextEncoder().encode(value).byteLength;
+}
+
+export function assertTransformInputWithinLimits(
+  request: TransformRequest
+): void {
+  const xmlBytes = utf8Bytes(request.xmlText);
+  if (xmlBytes > TRANSFORM_LIMITS.maxXmlBytes) {
+    throw new Error(
+      `XML input exceeds the ${TRANSFORM_LIMITS.maxXmlBytes}-byte execution limit.`
+    );
+  }
+
+  const xsltBytes = utf8Bytes(request.xsltText);
+  if (xsltBytes > TRANSFORM_LIMITS.maxXsltBytes) {
+    throw new Error(
+      `XSLT stylesheet exceeds the ${TRANSFORM_LIMITS.maxXsltBytes}-byte execution limit.`
+    );
+  }
+}
+
+export function assertTransformOutputWithinLimits(
+  result: TransformResult
+): void {
+  if (utf8Bytes(result.output) > TRANSFORM_LIMITS.maxOutputBytes) {
+    throw new Error(
+      `Transformation output exceeds the ${TRANSFORM_LIMITS.maxOutputBytes}-byte execution limit.`
+    );
+  }
+}
+
+export async function withTransformationTimeout<T>(
+  operation: () => Promise<T>,
+  timeoutMs: number = TRANSFORM_LIMITS.timeoutMs
+): Promise<T> {
+  let timer: number | undefined;
+  try {
+    return await Promise.race([
+      Promise.resolve().then(operation),
+      new Promise<never>((_resolve, reject) => {
+        timer = window.setTimeout(
+          () =>
+            reject(
+              new Error(
+                `Transformation exceeded the ${timeoutMs}-millisecond execution limit.`
+              )
+            ),
+          timeoutMs
+        );
+      }),
+    ]);
+  } finally {
+    if (timer !== undefined) window.clearTimeout(timer);
+  }
+}