chore: import upstream snapshot with attribution

2026-07-13 13:32:57 +08:00
commit cd420f9332
4811 changed files with 884702 additions and 0 deletions
@@ -0,0 +1,47 @@
+/**
+ * Cursor encoding for keyset pagination over `(created_at, run_id)`.
+ *
+ * The list query orders by the composite key `(created_at, run_id)`, so a sound
+ * cursor must carry BOTH components — cutting on `run_id` alone re-includes and
+ * skips rows whenever `run_id` order diverges from `created_at` order.
+ *
+ * A cursor is an opaque URL-safe base64 token wrapping `{ c: createdAtMs, r:
+ * runId }`. Cursors are server-issued (the SDK just echoes
+ * `pagination.next`/`previous` back), so this format needs no client update.
+ *
+ * Legacy cursors were the bare internal run_id (a cuid). They are detected by
+ * decode failure: a cuid base64-decodes to non-JSON bytes, so it falls through
+ * to `{ kind: "legacy" }` and the old (knowingly unsound) `run_id`-only
+ * predicate. In-flight legacy cursors keep working and drain naturally.
+ */
+
+import { z } from "zod";
+
+export type DecodedRunsCursor =
+  | { kind: "composite"; createdAt: number; runId: string }
+  | { kind: "legacy"; runId: string };
+
+// `c` = created_at (ms since epoch), `r` = run_id. Short keys keep the token small.
+const CompositeCursor = z.object({
+  c: z.number().int(),
+  r: z.string().min(1),
+});
+
+export function encodeRunsCursor(createdAtMs: number, runId: string): string {
+  return Buffer.from(JSON.stringify({ c: createdAtMs, r: runId })).toString("base64url");
+}
+
+export function decodeRunsCursor(cursor: string): DecodedRunsCursor {
+  try {
+    const parsed = CompositeCursor.safeParse(
+      JSON.parse(Buffer.from(cursor, "base64url").toString("utf8"))
+    );
+    if (parsed.success) {
+      return { kind: "composite", createdAt: parsed.data.c, runId: parsed.data.r };
+    }
+  } catch {
+    // JSON.parse threw — not a composite cursor.
+  }
+
+  return { kind: "legacy", runId: cursor };
+}