1 files changed, 221 insertions, 0 deletions
diff --git a/dom/workers/loader/CacheLoadHandler.h b/dom/workers/loader/CacheLoadHandler.h
new file mode 100644
index 0000000000..b1e164b79e
--- /dev/null
+++ b/dom/workers/loader/CacheLoadHandler.h
@@ -0,0 +1,221 @@
+/* -*- 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_workers_CacheLoadHandler_h__
+#define mozilla_dom_workers_CacheLoadHandler_h__
+
+#include "nsIContentPolicy.h"
+#include "nsIInputStreamPump.h"
+#include "nsIStreamLoader.h"
+#include "nsStringFwd.h"
+#include "nsStreamUtils.h"
+
+#include "mozilla/StaticPrefs_browser.h"
+#include "mozilla/dom/CacheBinding.h"
+#include "mozilla/dom/ChannelInfo.h"
+#include "mozilla/dom/Promise.h"
+#include "mozilla/dom/PromiseNativeHandler.h"
+#include "mozilla/dom/ScriptLoadHandler.h"
+#include "mozilla/dom/cache/Cache.h"
+#include "mozilla/dom/cache/CacheStorage.h"
+#include "mozilla/dom/WorkerCommon.h"
+#include "mozilla/dom/WorkerRef.h"
+
+#include "mozilla/dom/workerinternals/ScriptLoader.h"
+
+using mozilla::dom::cache::Cache;
+using mozilla::dom::cache::CacheStorage;
+using mozilla::ipc::PrincipalInfo;
+
+namespace mozilla::dom {
+
+class WorkerLoadContext;
+
+namespace workerinternals::loader {
+
+/*
+ * [DOMDOC] CacheLoadHandler for Workers
+ *
+ * A LoadHandler is a ScriptLoader helper class that reacts to an
+ * nsIStreamLoader's events for loading JS scripts. It is primarily responsible
+ * for decoding the stream into UTF8 or UTF16. Additionally, it takes care of
+ * any work that needs to follow the completion of a stream. Every LoadHandler
+ * also manages additional tasks for the type of load that it is doing.
+ *
+ * CacheLoadHandler is a specialized LoadHandler used by ServiceWorkers to
+ * implement the installation model used by ServiceWorkers to support running
+ * offline. When a ServiceWorker is installed, its main script is evaluated and
+ * all script resources that are loaded are saved. The spec does not specify the
+ * storage mechanism for this, but we chose to reuse the Cache API[1] mechanism
+ * that we expose to content to also store the script and its dependencies. We
+ * store the script resources in a special chrome namespace CacheStorage that is
+ * not visible to content. Each distinct ServiceWorker installation gets its own
+ * Cache keyed by a randomly-generated UUID.
+ *
+ * In terms of specification, this class implements step 4 of
+ * https://w3c.github.io/ServiceWorker/#importscripts
+ *
+ * Relationship to NetworkLoadHandler
+ *
+ * During ServiceWorker installation, the CacheLoadHandler falls back on the
+ * NetworkLoadHandler by calling `mLoader->LoadScript(...)`. If a script has not
+ * been seen before, then we will fall back on loading from the network.
+ * However, if the ServiceWorker is already installed, an error will be
+ * generated and the ServiceWorker will fail to load, per spec.
+ *
+ * CacheLoadHandler does not persist some pieces of information, such as the
+ * sourceMapUrl. Also, the DOM Cache API storage does not yet support alternate
+ * data streams for JS Bytecode or WASM caching; this is tracked by Bug 1336199.
+ *
+ * [1]: https://developer.mozilla.org/en-US/docs/Web/API/caches
+ *
+ */
+
+class CacheLoadHandler final : public PromiseNativeHandler,
+                               public nsIStreamLoaderObserver {
+ public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSISTREAMLOADEROBSERVER
+
+  CacheLoadHandler(ThreadSafeWorkerRef* aWorkerRef,
+                   ThreadSafeRequestHandle* aRequestHandle,
+                   bool aIsWorkerScript,
+                   bool aOnlyExistingCachedResourcesAllowed,
+                   WorkerScriptLoader* aLoader);
+
+  void Fail(nsresult aRv);
+
+  void Load(Cache* aCache);
+
+  virtual void ResolvedCallback(JSContext* aCx, JS::Handle<JS::Value> aValue,
+                                ErrorResult& aRv) override;
+
+  virtual void RejectedCallback(JSContext* aCx, JS::Handle<JS::Value> aValue,
+                                ErrorResult& aRv) override;
+
+ private:
+  ~CacheLoadHandler() { AssertIsOnMainThread(); }
+
+  nsresult DataReceivedFromCache(const uint8_t* aString, uint32_t aStringLen,
+                                 const mozilla::dom::ChannelInfo& aChannelInfo,
+                                 UniquePtr<PrincipalInfo> aPrincipalInfo,
+                                 const nsACString& aCSPHeaderValue,
+                                 const nsACString& aCSPReportOnlyHeaderValue,
+                                 const nsACString& aReferrerPolicyHeaderValue);
+  void DataReceived();
+
+  RefPtr<ThreadSafeRequestHandle> mRequestHandle;
+  const RefPtr<WorkerScriptLoader> mLoader;
+  RefPtr<ThreadSafeWorkerRef> mWorkerRef;
+  const bool mIsWorkerScript;
+  bool mFailed;
+  bool mOnlyExistingCachedResourcesAllowed;
+  nsCOMPtr<nsIInputStreamPump> mPump;
+  nsCOMPtr<nsIURI> mBaseURI;
+  mozilla::dom::ChannelInfo mChannelInfo;
+  UniquePtr<PrincipalInfo> mPrincipalInfo;
+  UniquePtr<ScriptDecoder> mDecoder;
+  nsCString mCSPHeaderValue;
+  nsCString mCSPReportOnlyHeaderValue;
+  nsCString mReferrerPolicyHeaderValue;
+  nsCOMPtr<nsISerialEventTarget> mMainThreadEventTarget;
+};
+
+/*
+ * CacheCreator
+ *
+ * The CacheCreator is responsible for maintaining a CacheStorage for the
+ * purposes of caching ServiceWorkers (see comment on CacheLoadHandler). In
+ * addition, it tracks all CacheLoadHandlers and is used for cleanup once
+ * loading has finished.
+ *
+ */
+
+class CacheCreator final : public PromiseNativeHandler {
+ public:
+  NS_DECL_ISUPPORTS
+
+  explicit CacheCreator(WorkerPrivate* aWorkerPrivate);
+
+  void AddLoader(MovingNotNull<RefPtr<CacheLoadHandler>> aLoader) {
+    AssertIsOnMainThread();
+    MOZ_ASSERT(!mCacheStorage);
+    mLoaders.AppendElement(std::move(aLoader));
+  }
+
+  virtual void ResolvedCallback(JSContext* aCx, JS::Handle<JS::Value> aValue,
+                                ErrorResult& aRv) override;
+
+  virtual void RejectedCallback(JSContext* aCx, JS::Handle<JS::Value> aValue,
+                                ErrorResult& aRv) override;
+
+  // Try to load from cache with aPrincipal used for cache access.
+  nsresult Load(nsIPrincipal* aPrincipal);
+
+  Cache* Cache_() const {
+    AssertIsOnMainThread();
+    MOZ_ASSERT(mCache);
+    return mCache;
+  }
+
+  nsIGlobalObject* Global() const {
+    AssertIsOnMainThread();
+    MOZ_ASSERT(mSandboxGlobalObject);
+    return mSandboxGlobalObject;
+  }
+
+  void DeleteCache(nsresult aReason);
+
+ private:
+  ~CacheCreator() = default;
+
+  nsresult CreateCacheStorage(nsIPrincipal* aPrincipal);
+
+  void FailLoaders(nsresult aRv);
+
+  RefPtr<Cache> mCache;
+  RefPtr<CacheStorage> mCacheStorage;
+  nsCOMPtr<nsIGlobalObject> mSandboxGlobalObject;
+  nsTArray<NotNull<RefPtr<CacheLoadHandler>>> mLoaders;
+
+  nsString mCacheName;
+  OriginAttributes mOriginAttributes;
+};
+
+/*
+ * CachePromiseHandler
+ *
+ * This promise handler is used to track if a ServiceWorker has been written to
+ * Cache. It is responsible for tracking the state of the ServiceWorker being
+ * cached. It also handles cancelling caching of a ServiceWorker if loading is
+ * interrupted. It is initialized by the NetworkLoadHandler as part of the first
+ * load of a ServiceWorker.
+ *
+ */
+class CachePromiseHandler final : public PromiseNativeHandler {
+ public:
+  NS_DECL_ISUPPORTS
+
+  CachePromiseHandler(WorkerScriptLoader* aLoader,
+                      ThreadSafeRequestHandle* aRequestHandle);
+
+  virtual void ResolvedCallback(JSContext* aCx, JS::Handle<JS::Value> aValue,
+                                ErrorResult& aRv) override;
+
+  virtual void RejectedCallback(JSContext* aCx, JS::Handle<JS::Value> aValue,
+                                ErrorResult& aRv) override;
+
+ private:
+  ~CachePromiseHandler() { AssertIsOnMainThread(); }
+
+  RefPtr<WorkerScriptLoader> mLoader;
+  RefPtr<ThreadSafeRequestHandle> mRequestHandle;
+};
+
+}  // namespace workerinternals::loader
+}  // namespace mozilla::dom
+
+#endif /* mozilla_dom_workers_CacheLoadHandler_h__ */