1 files changed, 310 insertions, 0 deletions
diff --git a/dom/fetch/Fetch.h b/dom/fetch/Fetch.h
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+/* -*- 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_Fetch_h
+#define mozilla_dom_Fetch_h
+
+#include "mozilla/Attributes.h"
+#include "nsCOMPtr.h"
+#include "nsError.h"
+#include "nsProxyRelease.h"
+#include "nsString.h"
+
+#include "mozilla/DebugOnly.h"
+#include "mozilla/dom/AbortSignal.h"
+#include "mozilla/dom/BodyConsumer.h"
+#include "mozilla/dom/Promise.h"
+#include "mozilla/dom/FetchStreamReader.h"
+#include "mozilla/dom/ReadableStream.h"
+#include "mozilla/dom/ReadableStreamDefaultReaderBinding.h"
+#include "mozilla/dom/RequestBinding.h"
+#include "mozilla/dom/workerinternals/RuntimeService.h"
+
+class nsIGlobalObject;
+class nsIEventTarget;
+
+namespace mozilla {
+class ErrorResult;
+
+namespace ipc {
+class PrincipalInfo;
+}  // namespace ipc
+
+namespace dom {
+
+class BlobOrArrayBufferViewOrArrayBufferOrFormDataOrURLSearchParamsOrUSVString;
+class
+    BlobOrArrayBufferViewOrArrayBufferOrFormDataOrURLSearchParamsOrReadableStreamOrUSVString;
+class BlobImpl;
+class InternalRequest;
+class
+    OwningBlobOrArrayBufferViewOrArrayBufferOrFormDataOrURLSearchParamsOrUSVString;
+
+class ReadableStreamDefaultReader;
+class RequestOrUSVString;
+class WorkerPrivate;
+
+enum class CallerType : uint32_t;
+
+already_AddRefed<Promise> FetchRequest(nsIGlobalObject* aGlobal,
+                                       const RequestOrUSVString& aInput,
+                                       const RequestInit& aInit,
+                                       CallerType aCallerType,
+                                       ErrorResult& aRv);
+
+nsresult UpdateRequestReferrer(nsIGlobalObject* aGlobal,
+                               InternalRequest* aRequest);
+
+namespace fetch {
+using BodyInit =
+    BlobOrArrayBufferViewOrArrayBufferOrFormDataOrURLSearchParamsOrUSVString;
+using ResponseBodyInit =
+    BlobOrArrayBufferViewOrArrayBufferOrFormDataOrURLSearchParamsOrReadableStreamOrUSVString;
+using OwningBodyInit =
+    OwningBlobOrArrayBufferViewOrArrayBufferOrFormDataOrURLSearchParamsOrUSVString;
+};  // namespace fetch
+
+/*
+ * Creates an nsIInputStream based on the fetch specifications 'extract a byte
+ * stream algorithm' - http://fetch.spec.whatwg.org/#concept-bodyinit-extract.
+ * Stores content type in out param aContentType.
+ */
+nsresult ExtractByteStreamFromBody(const fetch::OwningBodyInit& aBodyInit,
+                                   nsIInputStream** aStream,
+                                   nsCString& aContentType,
+                                   uint64_t& aContentLength);
+
+/*
+ * Non-owning version.
+ */
+nsresult ExtractByteStreamFromBody(const fetch::BodyInit& aBodyInit,
+                                   nsIInputStream** aStream,
+                                   nsCString& aContentType,
+                                   uint64_t& aContentLength);
+
+/*
+ * Non-owning version. This method should go away when BodyInit will contain
+ * ReadableStream.
+ */
+nsresult ExtractByteStreamFromBody(const fetch::ResponseBodyInit& aBodyInit,
+                                   nsIInputStream** aStream,
+                                   nsCString& aContentType,
+                                   uint64_t& aContentLength);
+
+/*
+ * FetchBody's body consumption uses nsIInputStreamPump to read from the
+ * underlying stream to a block of memory, which is then adopted by
+ * ContinueConsumeBody() and converted to the right type based on the JS
+ * function called.
+ *
+ * Use of the nsIInputStreamPump complicates things on the worker thread.
+ * The solution used here is similar to WebSockets.
+ * The difference is that we are only interested in completion and not data
+ * events, and nsIInputStreamPump can only deliver completion on the main
+ * thread.
+ *
+ * Before starting the pump on the main thread, we addref the FetchBody to keep
+ * it alive. Then we add a feature, to track the status of the worker.
+ *
+ * ContinueConsumeBody() is the function that cleans things up in both success
+ * and error conditions and so all callers call it with the appropriate status.
+ *
+ * Once the read is initiated on the main thread there are two possibilities.
+ *
+ * 1) Pump finishes before worker has finished Running.
+ *    In this case we adopt the data and dispatch a runnable to the worker,
+ *    which derefs FetchBody and removes the feature and resolves the Promise.
+ *
+ * 2) Pump still working while worker has stopped Running.
+ *    The feature is Notify()ed and ContinueConsumeBody() is called with
+ *    NS_BINDING_ABORTED. We first Cancel() the pump using a sync runnable to
+ *    ensure that mFetchBody remains alive (since mConsumeBodyPump is strongly
+ *    held by it) until pump->Cancel() is called. OnStreamComplete() will not
+ *    do anything if the error code is NS_BINDING_ABORTED, so we don't have to
+ *    worry about keeping anything alive.
+ *
+ * The pump is always released on the main thread.
+ */
+
+class FetchBodyBase : public nsISupports {
+ public:
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_CLASS(FetchBodyBase)
+
+ protected:
+  virtual ~FetchBodyBase() = default;
+
+  RefPtr<ReadableStream> mReadableStreamBody;
+};
+
+template <class Derived>
+class FetchBody : public FetchBodyBase, public AbortFollower {
+ public:
+  using FetchBodyBase::QueryInterface;
+
+  NS_INLINE_DECL_REFCOUNTING_INHERITED(FetchBody, FetchBodyBase)
+
+  bool BodyUsed() const;
+
+  already_AddRefed<Promise> ArrayBuffer(JSContext* aCx, ErrorResult& aRv) {
+    return ConsumeBody(aCx, BodyConsumer::CONSUME_ARRAYBUFFER, aRv);
+  }
+
+  already_AddRefed<Promise> Blob(JSContext* aCx, ErrorResult& aRv) {
+    return ConsumeBody(aCx, BodyConsumer::CONSUME_BLOB, aRv);
+  }
+
+  already_AddRefed<Promise> FormData(JSContext* aCx, ErrorResult& aRv) {
+    return ConsumeBody(aCx, BodyConsumer::CONSUME_FORMDATA, aRv);
+  }
+
+  already_AddRefed<Promise> Json(JSContext* aCx, ErrorResult& aRv) {
+    return ConsumeBody(aCx, BodyConsumer::CONSUME_JSON, aRv);
+  }
+
+  already_AddRefed<Promise> Text(JSContext* aCx, ErrorResult& aRv) {
+    return ConsumeBody(aCx, BodyConsumer::CONSUME_TEXT, aRv);
+  }
+
+  already_AddRefed<ReadableStream> GetBody(JSContext* aCx, ErrorResult& aRv);
+  void GetMimeType(nsACString& aMimeType, nsACString& aMixedCaseMimeType);
+
+  const nsACString& BodyBlobURISpec() const;
+
+  const nsAString& BodyLocalPath() const;
+
+  // If the body contains a ReadableStream body object, this method produces a
+  // tee() of it.
+  //
+  // This is marked as a script boundary minimize changes required for
+  // annotation while we work out how to correctly annotate this code.
+  // Tracked in Bug 1750650.
+  MOZ_CAN_RUN_SCRIPT_BOUNDARY
+  void MaybeTeeReadableStreamBody(JSContext* aCx, ReadableStream** aBodyOut,
+                                  FetchStreamReader** aStreamReader,
+                                  nsIInputStream** aInputStream,
+                                  ErrorResult& aRv);
+
+  // Utility public methods accessed by various runnables.
+
+  // This method _must_ be called in order to set the body as used. If the body
+  // is a ReadableStream, this method will start reading the stream.
+  // More in details, this method does:
+  // 1) It uses an internal flag to track if the body is used.  This is tracked
+  // separately from the ReadableStream disturbed state due to purely native
+  // streams.
+  // 2) If there is a ReadableStream reflector for the native stream it is
+  // Locked.
+  // 3) If there is a JS ReadableStream then we begin pumping it into the native
+  // body stream.  This effectively locks and disturbs the stream.
+  //
+  // Note that JSContext is used only if there is a ReadableStream (this can
+  // happen because the body is a ReadableStream or because attribute body has
+  // already been used by content). If something goes wrong using
+  // ReadableStream, errors will be reported via ErrorResult and not as JS
+  // exceptions in JSContext. This is done in order to have a centralized error
+  // reporting way.
+  //
+  // Exceptions generated when reading from the ReadableStream are directly sent
+  // to the Console.
+  void SetBodyUsed(JSContext* aCx, ErrorResult& aRv);
+
+  virtual AbortSignalImpl* GetSignalImpl() const = 0;
+
+  virtual AbortSignalImpl* GetSignalImplToConsumeBody() const = 0;
+
+  // AbortFollower
+  void RunAbortAlgorithm() override;
+
+  already_AddRefed<Promise> ConsumeBody(JSContext* aCx,
+                                        BodyConsumer::ConsumeType aType,
+                                        ErrorResult& aRv);
+
+ protected:
+  nsCOMPtr<nsIGlobalObject> mOwner;
+
+  // This is the Reader used to retrieve data from the body. This needs to be
+  // traversed by subclasses.
+  RefPtr<FetchStreamReader> mFetchStreamReader;
+
+  explicit FetchBody(nsIGlobalObject* aOwner);
+
+  virtual ~FetchBody();
+
+  void SetReadableStreamBody(JSContext* aCx, ReadableStream* aBody);
+
+ private:
+  Derived* DerivedClass() const {
+    return static_cast<Derived*>(const_cast<FetchBody*>(this));
+  }
+
+  void LockStream(JSContext* aCx, ReadableStream* aStream, ErrorResult& aRv);
+
+  void AssertIsOnTargetThread() {
+    MOZ_ASSERT(NS_IsMainThread() == !GetCurrentThreadWorkerPrivate());
+  }
+
+  // Only ever set once, always on target thread.
+  bool mBodyUsed;
+
+  // The main-thread event target for runnable dispatching.
+  nsCOMPtr<nsISerialEventTarget> mMainThreadEventTarget;
+};
+
+class EmptyBody final : public FetchBody<EmptyBody> {
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_INHERITED(EmptyBody,
+                                                         FetchBody<EmptyBody>)
+
+ public:
+  static already_AddRefed<EmptyBody> Create(
+      nsIGlobalObject* aGlobal, mozilla::ipc::PrincipalInfo* aPrincipalInfo,
+      AbortSignalImpl* aAbortSignalImpl, const nsACString& aMimeType,
+      const nsACString& aMixedCaseMimeType, ErrorResult& aRv);
+
+  nsIGlobalObject* GetParentObject() const { return mOwner; }
+
+  AbortSignalImpl* GetSignalImpl() const override { return mAbortSignalImpl; }
+  AbortSignalImpl* GetSignalImplToConsumeBody() const final { return nullptr; }
+
+  const UniquePtr<mozilla::ipc::PrincipalInfo>& GetPrincipalInfo() const {
+    return mPrincipalInfo;
+  }
+
+  void GetMimeType(nsACString& aMimeType, nsACString& aMixedCaseMimeType) {
+    aMimeType = mMimeType;
+    aMixedCaseMimeType = mMixedCaseMimeType;
+  }
+
+  void GetBody(nsIInputStream** aStream, int64_t* aBodyLength = nullptr);
+
+  using FetchBody::BodyBlobURISpec;
+
+  const nsACString& BodyBlobURISpec() const { return EmptyCString(); }
+
+  using FetchBody::BodyLocalPath;
+
+  const nsAString& BodyLocalPath() const { return EmptyString(); }
+
+ private:
+  EmptyBody(nsIGlobalObject* aGlobal,
+            mozilla::ipc::PrincipalInfo* aPrincipalInfo,
+            AbortSignalImpl* aAbortSignalImpl, const nsACString& aMimeType,
+            const nsACString& aMixedCaseMimeType,
+            already_AddRefed<nsIInputStream> aBodyStream);
+
+  ~EmptyBody();
+
+  UniquePtr<mozilla::ipc::PrincipalInfo> mPrincipalInfo;
+  RefPtr<AbortSignalImpl> mAbortSignalImpl;
+  nsCString mMimeType;
+  nsCString mMixedCaseMimeType;
+  nsCOMPtr<nsIInputStream> mBodyStream;
+};
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_Fetch_h