Import source: app/backend/src/lib/sanitize

Import the existing local project snapshot. This commit organizes existing files; it does not represent newly developed functionality.

app/backend/src/lib/sanitize.ts

@@ -0,0 +1,18 @@
+import sanitizeHtml from 'sanitize-html';
+
+const COMMENT_OPTIONS: sanitizeHtml.IOptions = {
+  allowedTags: ['b', 'i', 'em', 'strong', 'a', 'code', 'br'],
+  allowedAttributes: {
+    a: ['href', 'title'],
+  },
+  allowedSchemes: ['https'],
+  disallowedTagsMode: 'discard',
+};
+
+export function sanitizeComment(input: string): string {
+  return sanitizeHtml(input, COMMENT_OPTIONS);
+}
+
+export function stripHtml(input: string): string {
+  return sanitizeHtml(input, { allowedTags: [], allowedAttributes: {} });
+}