1 files changed, 72 insertions, 0 deletions
diff --git a/dom/serviceworkers/FetchEventOpParent.h b/dom/serviceworkers/FetchEventOpParent.h
new file mode 100644
index 0000000000..ebac93bc10
--- /dev/null
+++ b/dom/serviceworkers/FetchEventOpParent.h
@@ -0,0 +1,72 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_fetcheventopparent_h__
+#define mozilla_dom_fetcheventopparent_h__
+
+#include "nsISupports.h"
+
+#include "mozilla/Tuple.h"
+#include "mozilla/dom/FetchEventOpProxyParent.h"
+#include "mozilla/dom/PFetchEventOpParent.h"
+
+namespace mozilla::dom {
+
+class FetchEventOpParent final : public PFetchEventOpParent {
+  friend class PFetchEventOpParent;
+
+ public:
+  NS_INLINE_DECL_REFCOUNTING(FetchEventOpParent)
+
+  FetchEventOpParent() = default;
+
+  // Transition from the Pending state to the Started state. Returns the preload
+  // response and response end args, if it has already arrived.
+  Tuple<Maybe<ParentToParentInternalResponse>, Maybe<ResponseEndArgs>> OnStart(
+      MovingNotNull<RefPtr<FetchEventOpProxyParent>> aFetchEventOpProxyParent);
+
+  // Transition from the Started state to the Finished state.
+  void OnFinish();
+
+ private:
+  ~FetchEventOpParent() = default;
+
+  // IPDL methods
+
+  mozilla::ipc::IPCResult RecvPreloadResponse(
+      ParentToParentInternalResponse&& aResponse);
+
+  mozilla::ipc::IPCResult RecvPreloadResponseEnd(ResponseEndArgs&& aArgs);
+
+  void ActorDestroy(ActorDestroyReason) override;
+
+  struct Pending {
+    Maybe<ParentToParentInternalResponse> mPreloadResponse;
+    Maybe<ResponseEndArgs> mEndArgs;
+  };
+
+  struct Started {
+    NotNull<RefPtr<FetchEventOpProxyParent>> mFetchEventOpProxyParent;
+  };
+
+  struct Finished {};
+
+  using State = Variant<Pending, Started, Finished>;
+
+  // Tracks the state of the fetch event.
+  //
+  // Pending:  the fetch event is waiting in RemoteWorkerController::mPendingOps
+  //           and if the preload response arrives, we have to save it.
+  // Started:  the FetchEventOpProxyParent has been created, and if the preload
+  //           response arrives then we should forward it.
+  // Finished: the response has been propagated to the parent process, if the
+  //           preload response arrives now then we simply drop it.
+  State mState = AsVariant(Pending());
+};
+
+}  // namespace mozilla::dom
+
+#endif  // mozilla_dom_fetcheventopparent_h__