net: Add SetUploadStream method to URLFetcher.

net/url_request/url_fetcher.h

 // Copyright (c) 2012 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 NET_URL_REQUEST_URL_FETCHER_H_
 #define NET_URL_REQUEST_URL_FETCHER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 74 matching lines @@
     DELETE_REQUEST,   // DELETE is already taken on Windows.
                       // <winnt.h> defines a DELETE macro.
     PUT,
     PATCH,
   };
 
   // Used by SetURLRequestUserData.  The callback should make a fresh
   // base::SupportsUserData::Data object every time it's called.
   typedef base::Callback<base::SupportsUserData::Data*()> CreateDataCallback;
 
+  // Used by SetUploadStreamFactory. The callback should assign a fresh upload
+  // data stream every time it's called.
+  typedef base::Callback<scoped_ptr<UploadDataStream>()>
+      CreateUploadStreamCallback;
+
   virtual ~URLFetcher();
 
   // |url| is the URL to send the request to.
   // |request_type| is the type of request to make.
   // |d| the object that will receive the callback on fetch completion.
   // Caller is responsible for destroying the returned URLFetcher.
   static URLFetcher* Create(const GURL& url,
                             URLFetcher::RequestType request_type,
                             URLFetcherDelegate* d);
 
@@ skipping 37 matching lines @@
   // |range_offset| and |range_length| specify the range of the part
   // to be uploaded. To upload the whole file, (0, kuint64max) can be used.
   // |file_task_runner| will be used for all file operations.
   virtual void SetUploadFilePath(
       const std::string& upload_content_type,
       const base::FilePath& file_path,
       uint64 range_offset,
       uint64 range_length,
       scoped_refptr<base::TaskRunner> file_task_runner) = 0;
 
+  // Sets data only needed by POSTs.  All callers making POST requests should
+  // call one of the SetUpload* methods before the request is started.
+  // |upload_content_type| is the MIME type of the content, while |callback| is
+  // the callback to create the upload data stream (the Content-Length header
+  // value will be set to the length of this data).

[mmenke, 2015/01/15 15:38:54]

Worth mentioning the callback may be called multiple times - can see people
assuming otherwise, and then causing crashes in rare cases, which have a crash
stack that make it look like a net/ bug.

[hirono, 2015/01/16 03:55:58]

Done.

+  virtual void SetUploadStreamFactory(
+      const std::string& upload_content_type,
+      const CreateUploadStreamCallback& callback) = 0;
+
   // Indicates that the POST data is sent via chunked transfer encoding.
   // This may only be called before calling Start().
   // Use AppendChunkToUpload() to give the data chunks after calling Start().
   virtual void SetChunkedUpload(const std::string& upload_content_type) = 0;
 
   // Adds the given bytes to a request's POST data transmitted using chunked
   // transfer encoding.
   // This method should be called ONLY after calling Start().
   virtual void AppendChunkToUpload(const std::string& data,
                                    bool is_last_chunk) = 0;
@@ skipping 139 matching lines @@
   // be removed once the URLFetcher is destroyed.  User should not take
   // ownership more than once, or call this method after taking ownership.
   virtual bool GetResponseAsFilePath(
       bool take_ownership,
       base::FilePath* out_response_path) const = 0;
 };
 
 }  // namespace net
 
 #endif  // NET_URL_REQUEST_URL_FETCHER_H_