Add read-only access to POST data for webRequest's onBeforeRequest

chrome/browser/extensions/api/web_request/upload_data_presenter.cc

+// 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.
+
+#include "chrome/browser/extensions/api/web_request/upload_data_presenter.h"
+
+#include "base/file_path.h"
+#include "base/string_util.h"
+#include "base/values.h"
+#include "chrome/browser/extensions/api/web_request/form_data_parser.h"
+#include "chrome/browser/extensions/api/web_request/web_request_api_constants.h"
+#include "net/base/upload_element.h"
+#include "net/url_request/url_request.h"
+
+using base::BinaryValue;
+using base::DictionaryValue;
+using base::ListValue;
+using base::StringValue;
+using base::Value;
+
+namespace keys = extension_web_request_api_constants;
+
+namespace {
+
+// Takes |dictionary| of <string, list of strings> pairs, and gets the list
+// for |key|, creating it if necessary.
+ListValue* GetOrCreateList(DictionaryValue* dictionary,
+                           const std::string& key) {
+  ListValue* list = NULL;
+  if (!dictionary->GetList(key, &list)) {
+    list = new ListValue();
+    dictionary->Set(key, list);
+  }
+  return list;
+}
+
+}  // namespace
+
+namespace extensions {
+
+// Implementation of UploadDataPresenter.
+
+UploadDataPresenter::~UploadDataPresenter() {}
+
+// Implementation of ChunkedErrorPresenter.
+
+ChunkedErrorPresenter::ChunkedErrorPresenter(const net::URLRequest* request)
+    : chunks_found_(IsTransferEncodingChunked(request)) {
+}
+
+ChunkedErrorPresenter::~ChunkedErrorPresenter() {}
+
+// static
+bool ChunkedErrorPresenter::IsTransferEncodingChunked(
+    const net::URLRequest* request){
+  std::string transfer_encoding;
+  const net::HttpRequestHeaders& headers = request->extra_request_headers();
+  if (!headers.GetHeader(net::HttpRequestHeaders::kTransferEncoding,
+                         &transfer_encoding)) {
+    return false;
+  }
+  return base::strcasecmp(transfer_encoding.c_str(), "chunked") == 0;
+}
+
+void ChunkedErrorPresenter::FeedNext(const net::UploadElement& element) {
+  if (chunks_found_)
+    return;  // We already found a reason to report an error.
+
+  if (element.type() == net::UploadElement::TYPE_CHUNK)
+    chunks_found_ = true;
+}
+
+bool ChunkedErrorPresenter::Succeeded() {
+  return chunks_found_;
+}
+
+scoped_ptr<Value> ChunkedErrorPresenter::Result() {
+  if (!chunks_found_)
+    return scoped_ptr<Value>();
+
+  scoped_ptr<StringValue> error_string(new StringValue(
+      "Not supported: data is uploaded chunked."));
+  return error_string.PassAs<Value>();
+}
+
+// Implementation of RawDataPresenter.
+
+RawDataPresenter::RawDataPresenter()
+  : success_(true),
+    list_(new base::ListValue) {
+}
+RawDataPresenter::~RawDataPresenter() {}
+
+void RawDataPresenter::FeedNext(const net::UploadElement& element) {
+  if (!success_)
+    return;
+
+  switch (element.type()) {
+    case net::UploadElement::TYPE_BYTES:
+      FeedNextBytes(element.bytes(), element.bytes_length());
+      break;
+    case net::UploadElement::TYPE_CHUNK:
+      Abort();  // Chunks are not supported (yet).
+      break;
+    case net::UploadElement::TYPE_FILE:
+      // Insert the file path instead of the contents, which may be too large.
+      FeedNextFile(element.file_path().AsUTF8Unsafe());
+      break;
+  }
+}
+
+bool RawDataPresenter::Succeeded() {
+  return success_;
+}
+
+scoped_ptr<Value> RawDataPresenter::Result() {
+  if (!success_)
+    return scoped_ptr<Value>();
+
+  return list_.PassAs<Value>();
+}
+
+// static
+void RawDataPresenter::AppendResultWithKey(
+    ListValue* list, const char* key, Value* value) {
+  DictionaryValue* dictionary = new DictionaryValue;
+  dictionary->Set(key, value);
+  list->Append(dictionary);
+}
+
+void RawDataPresenter::Abort() {
+  success_ = false;
+  list_.reset();
+}
+
+void RawDataPresenter::FeedNextBytes(const char* bytes, size_t size) {
+  AppendResultWithKey(list_.get(), keys::kRequestBodyRawBytesKey,
+                      BinaryValue::CreateWithCopiedBuffer(bytes, size));
+}
+
+void RawDataPresenter::FeedNextFile(const std::string& filename) {
+  // Insert the file path instead of the contents, which may be too large.
+  AppendResultWithKey(list_.get(), keys::kRequestBodyRawFileKey,
+                      Value::CreateStringValue(filename));
+}
+
+// Implementation of ParsedDataPresenter.
+
+ParsedDataPresenter::ParsedDataPresenter(const net::URLRequest* request)
+  : parser_(FormDataParser::Create(request)),
+    success_(parser_.get() != NULL),
+    dictionary_(success_ ? new DictionaryValue() : NULL) {
+}
+
+ParsedDataPresenter::~ParsedDataPresenter() {}
+
+void ParsedDataPresenter::FeedNext(const net::UploadElement& element) {
+  if (!success_)
+    return;
+
+  if (element.type() != net::UploadElement::TYPE_BYTES) {
+    if (element.type() != net::UploadElement::TYPE_FILE) {
+      Abort();  // We do not handle blobs nor chunks.
+    }
+    return;  // But we just ignore files.
+  }
+  if (!parser_->SetSource(base::StringPiece(element.bytes(),
+                                            element.bytes_length()))) {
+    Abort();
+    return;
+  }
+
+  FormDataParser::Result result;
+  while (parser_->GetNextNameValue(&result)) {
+    GetOrCreateList(dictionary_.get(), result.name())->Append(
+        new StringValue(result.value()));
+  }
+}
+
+bool ParsedDataPresenter::Succeeded() {
+  if (success_ && !parser_->AllDataReadOK())
+    Abort();
+  return success_;
+}
+
+scoped_ptr<Value> ParsedDataPresenter::Result() {
+  if (success_)
+    return dictionary_.PassAs<Value>();
+  else
+    return scoped_ptr<Value>();
+}
+
+void ParsedDataPresenter::Abort() {
+  success_ = false;
+  dictionary_.reset();
+  parser_.reset();
+}
+
+}  // namespace extensions