Change AuthenticatingURLLoader to be a URLLoaderInterceptor

services/authenticating_url_loader/authenticating_url_loader_impl.cc

-// 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.
-
-#include "services/authenticating_url_loader/authenticating_url_loader_impl.h"
-
-#include "base/bind.h"
-#include "base/logging.h"
-#include "mojo/services/network/public/interfaces/network_service.mojom.h"
-
-namespace mojo {
-
-AuthenticatingURLLoaderImpl::AuthenticatingURLLoaderImpl(
-    InterfaceRequest<AuthenticatingURLLoader> request,
-    AuthenticatingURLLoaderFactoryImpl* factory)
-    : binding_(this, request.Pass()),
-      factory_(factory),
-      request_authorization_state_(REQUEST_INITIAL) {
-  binding_.set_error_handler(this);
-}
-
-AuthenticatingURLLoaderImpl::~AuthenticatingURLLoaderImpl() {
-}
-
-void AuthenticatingURLLoaderImpl::Start(
-    URLRequestPtr request,
-    const Callback<void(URLResponsePtr)>& callback) {
-  // TODO(blundell): If we need to handle requests with bodies, we'll need to
-  // do something here.
-  if (request->body) {
-    LOG(ERROR)
-        << "Cannot pass a request to AuthenticatingURLLoader that has a body";
-    callback.Run(nullptr);
-    return;
-  }
-  url_ = GURL(request->url);
-  auto_follow_redirects_ = request->auto_follow_redirects;
-  bypass_cache_ = request->bypass_cache;
-  headers_ = request->headers.Clone();
-  pending_request_callback_ = callback;
-  std::string token = factory_->GetCachedToken(url_);
-  if (token != "") {
-    auto auth_header = HttpHeader::New();
-    auth_header->name = "Authorization";
-    auth_header->value = "Bearer " + token;
-    request->headers.push_back(auth_header.Pass());
-  }
-  StartNetworkRequest(request.Pass());
-}
-
-void AuthenticatingURLLoaderImpl::FollowRedirect(
-    const Callback<void(URLResponsePtr)>& callback) {
-  mojo::String error;
-
-  if (!url_.is_valid() || !url_loader_) {
-    error = "No redirect to follow";
-  }
-
-  if (auto_follow_redirects_) {
-    error =
-        "FollowRedirect() should not be "
-        "called when auto_follow_redirects has been set";
-  }
-
-  if (request_authorization_state_ != REQUEST_INITIAL) {
-    error = "Not in the right state to follow a redirect";
-  }
-
-  if (!error.is_null()) {
-    LOG(ERROR) << "AuthenticatingURLLoader: " << error;
-    callback.Run(nullptr);
-    return;
-  }
-
-  pending_request_callback_ = callback;
-  FollowRedirectInternal();
-}
-
-void AuthenticatingURLLoaderImpl::StartNetworkRequest(URLRequestPtr request) {
-  factory_->network_service()->CreateURLLoader(mojo::GetProxy(&url_loader_));
-  url_loader_->Start(request.Pass(),
-                     base::Bind(&AuthenticatingURLLoaderImpl::OnLoadComplete,
-                                base::Unretained(this)));
-}
-
-void AuthenticatingURLLoaderImpl::OnConnectionError() {
-  factory_->OnURLLoaderError(this);
-  // The factory deleted this object.
-}
-
-void AuthenticatingURLLoaderImpl::OnLoadComplete(URLResponsePtr response) {
-  if (response->redirect_url) {
-    url_ = GURL(response->redirect_url);
-    request_authorization_state_ = REQUEST_INITIAL;
-
-    if (auto_follow_redirects_) {
-      FollowRedirectInternal();
-    } else {
-      // NOTE: We do not reset |url_loader_| here as it will be needed if the
-      // client calls |FollowRedirect()|.
-      pending_request_callback_.Run(response.Pass());
-    }
-    return;
-  }
-
-  url_loader_.reset();
-
-  if (response->status_code != 401 ||
-      request_authorization_state_ == REQUEST_USED_FRESH_AUTH_SERVICE_TOKEN) {
-    pending_request_callback_.Run(response.Pass());
-    return;
-  }
-
-  pending_response_ = response.Pass();
-
-  DCHECK(request_authorization_state_ == REQUEST_INITIAL ||
-         request_authorization_state_ ==
-             REQUEST_USED_CURRENT_AUTH_SERVICE_TOKEN);
-  if (request_authorization_state_ == REQUEST_INITIAL) {
-    request_authorization_state_ = REQUEST_USED_CURRENT_AUTH_SERVICE_TOKEN;
-  } else {
-    request_authorization_state_ = REQUEST_USED_FRESH_AUTH_SERVICE_TOKEN;
-  }
-  factory_->RetrieveToken(
-      url_, base::Bind(&AuthenticatingURLLoaderImpl::OnOAuth2TokenReceived,
-                       base::Unretained(this)));
-  return;
-}
-
-void AuthenticatingURLLoaderImpl::FollowRedirectInternal() {
-  DCHECK(url_.is_valid());
-  DCHECK(url_loader_);
-  DCHECK(request_authorization_state_ == REQUEST_INITIAL);
-
-  url_loader_->FollowRedirect(base::Bind(
-      &AuthenticatingURLLoaderImpl::OnLoadComplete, base::Unretained(this)));
-}
-
-void AuthenticatingURLLoaderImpl::OnOAuth2TokenReceived(std::string token) {
-  if (token.empty()) {
-    LOG(ERROR) << "Error while getting token";
-    pending_request_callback_.Run(pending_response_.Pass());
-    return;
-  }
-
-  auto auth_header = HttpHeader::New();
-  auth_header->name = "Authorization";
-  auth_header->value = "Bearer " + token;
-  Array<HttpHeaderPtr> headers;
-  if (headers_)
-    headers = headers_.Clone();
-  headers.push_back(auth_header.Pass());
-
-  URLRequestPtr request(mojo::URLRequest::New());
-  request->url = url_.spec();
-  request->auto_follow_redirects = false;
-  request->bypass_cache = bypass_cache_;
-  request->headers = headers.Pass();
-
-  StartNetworkRequest(request.Pass());
-}
-
-}  // namespace mojo