Initial implementation of Cronet Async API.

components/cronet/android/cronet_url_request_adapter.h

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_CRONET_ANDROID_CRONET_URL_REQUEST_ADAPTER_H_
+#define COMPONENTS_CRONET_ANDROID_CRONET_URL_REQUEST_ADAPTER_H_
+
+#include <string>
+
+#include "base/callback.h"
+#include "base/location.h"
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "net/base/request_priority.h"
+#include "net/http/http_request_headers.h"
+#include "net/url_request/url_request.h"
+#include "url/gurl.h"
+
+namespace base {
+class SingleThreadTaskRunner;
+}  // namespace base
+
+namespace net {
+class GrowableIOBuffer;
+class HttpResponseHeaders;
+}  // namespace net
+
+namespace cronet {
+
+class CronetURLRequestContextAdapter;
+
+// An adapter from the JNI CronetUrlRequest object to the Chromium URLRequest.
+// Created and configured from random thread. Start is posted to network
+// thread and all callbacks into CronetURLRequestAdapterDelegate are done on
+// network thread. Each delegate callback is expected to initiate next step like
+// FollowDeferredRedirect, ReadData or Destroy. All methods except those needed
+// to set up a request must be called exclusively on the network thread.
+class CronetURLRequestAdapter : public net::URLRequest::Delegate {
+ public:
+  // The delegate which is called when the request adapter completes a step.
+  // Always called on network thread.
+  class CronetURLRequestAdapterDelegate {
+   public:
+    // Called on redirect. Consumer should either destroy the request, or
+    // call FollowDeferredRedirect.
+    virtual void OnRedirect(const GURL& newLocation, int http_status_code) = 0;
+    // Called when response has started and headers have been received. Consumer
+    // should either destroy the request, or call ReadData.
+    virtual void OnResponseStarted(int http_status_code) = 0;
+    // Called when response bytes were read. Consumer should consume data and
+    // either destroy the request, or call ReadData. The request may only be
+    // destroyed after the embedder is done with |bytes|, as deleting the
+    // request frees the buffer.
+    virtual void OnBytesRead(unsigned char* bytes,
+                             int bytes_read) = 0;
+    // Called when response has finished successfully. Consumer should destroy
+    // the request.
+    virtual void OnRequestFinished() = 0;
+    // Called when response has finished with error. Consumer should destroy
+    // the request.
+    virtual void OnError(int net_error) = 0;
+
+    virtual ~CronetURLRequestAdapterDelegate() {}
+  };
+
+  CronetURLRequestAdapter(
+      CronetURLRequestContextAdapter* context,
+      scoped_ptr<CronetURLRequestAdapterDelegate> delegate,
+      const GURL& url,
+      net::RequestPriority priority);
+  ~CronetURLRequestAdapter() override;
+
+  // Methods called prior to Start are never called on network thread.
+
+  // Sets the request method GET, POST etc.
+  void set_method(const std::string& method) {
+    initial_method_ = method;
+  }
+
+  // Adds a header to the request before it starts.
+  void AddRequestHeader(const std::string& name, const std::string& value);
+
+  // Methods called on any thread.
+
+  // Posts tasks to network thread.
+  bool PostTaskToNetworkThread(const tracked_objects::Location& from_here,
+                               const base::Closure& task);
+
+  // Returns true if called on network thread.
+  bool IsOnNetworkThread() const;
+
+  // Methods called only on network thread.
+
+  // Starts the request.
+  void Start();
+
+  // Follows redirect.
+  void FollowDeferredRedirect();
+
+  // Reads more data.
+  void ReadData();
+
+  // Releases all resources for the request and deletes the object itself.
+  void Destroy();
+
+  // When called during a OnRedirect or OnResponseStarted callback, these
+  // methods return the corresponding response information.
+
+  // Gets all response headers, as a HttpResponseHeaders object. Returns NULL
+  // if the last attempted request received no headers.
+  const net::HttpResponseHeaders* GetResponseHeaders() const;
+
+  // Gets NPN or ALPN Negotiated Protocol (if any) from HttpResponseInfo.
+  const std::string& GetNegotiatedProtocol() const;
+
+  // Returns true if response is coming from the cache.
+  bool GetWasCached() const;
+
+  // Gets the total amount of body data received from network after
+  // SSL/SPDY/QUIC decoding and proxy handling.  Basically the size of the body
+  // prior to decompression.
+  int64 GetTotalReceivedBytes() const;
+
+  // net::URLRequest::Delegate overrides.
+  void OnReceivedRedirect(net::URLRequest* request,
+                          const net::RedirectInfo& redirect_info,
+                          bool* defer_redirect) override;
+  void OnResponseStarted(net::URLRequest* request) override;
+  void OnReadCompleted(net::URLRequest* request, int bytes_read) override;
+
+ private:
+  // Checks status of the request_adapter, return false if |is_success()| is
+  // true, otherwise report error and cancel request_adapter.
+  bool MaybeReportError(net::URLRequest* request) const;
+
+  CronetURLRequestContextAdapter* context_;
+  scoped_ptr<CronetURLRequestAdapterDelegate> delegate_;
+
+  const GURL initial_url_;
+  const net::RequestPriority initial_priority_;
+  std::string initial_method_;
+  net::HttpRequestHeaders initial_request_headers_;
+
+  scoped_refptr<net::IOBufferWithSize> read_buffer_;
+  scoped_ptr<net::URLRequest> url_request_;
+
+  DISALLOW_COPY_AND_ASSIGN(CronetURLRequestAdapter);
+};
+
+}  // namespace cronet
+
+#endif  // COMPONENTS_CRONET_ANDROID_CRONET_URL_REQUEST_ADAPTER_H_