Headless utility classes for making deterministic protocol handlers

headless/public/util/generic_url_request_job.cc

+// Copyright 2016 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 "headless/public/util/generic_url_request_job.h"
+
+#include <string.h>
+#include <algorithm>
+
+#include "base/logging.h"
+#include "headless/public/util/url_request_dispatcher.h"
+#include "net/base/io_buffer.h"
+#include "net/base/net_errors.h"
+#include "net/base/registry_controlled_domains/registry_controlled_domain.h"
+#include "net/cookies/cookie_store.h"
+#include "net/http/http_response_headers.h"
+#include "net/url_request/url_request_context.h"
+
+namespace headless {
+namespace {
+
+// True if the request method is "safe" (per section 4.2.1 of RFC 7231).
+bool IsMethodSafe(const std::string& method) {
+  return method == "GET" || method == "HEAD" || method == "OPTIONS" ||
+         method == "TRACE";
+}
+
+}  // namespace
+
+GenericURLRequestJob::GenericURLRequestJob(
+    net::URLRequest* request,
+    net::NetworkDelegate* network_delegate,
+    URLRequestDispatcher* url_request_dispatcher,
+    std::unique_ptr<URLFetcher> url_fetcher,
+    Delegate* delegate)
+    : ManagedDispatchURLRequestJob(request,
+                                   network_delegate,
+                                   url_request_dispatcher),
+      url_fetcher_(std::move(url_fetcher)),
+      delegate_(delegate),
+      weak_factory_(this) {}
+
+GenericURLRequestJob::~GenericURLRequestJob() = default;
+
+void GenericURLRequestJob::SetExtraRequestHeaders(
+    const net::HttpRequestHeaders& headers) {
+  extra_request_headers_ = headers;
+}
+
+void GenericURLRequestJob::Start() {
+  auto callback = [this](RewriteResult result, const GURL& url) {
+    switch (result) {
+      case RewriteResult::kAllow:
+        // Note that we use the rewritten url for selecting cookies.
+        // Also, rewriting does not affect the request initiator.
+        PrepareCookies(url, url::Origin(url));
+        break;
+      case RewriteResult::kDeny:
+        DispatchStartError(net::ERR_FILE_NOT_FOUND);
+        break;
+      case RewriteResult::kFailure:
+        DispatchStartError(net::ERR_UNEXPECTED);
+        break;
+      default:
+        DCHECK(false);
+    }
+  };
+
+  if (!delegate_->BlockOrRewriteRequest(request_->url(), request_->referrer(),
+                                        callback)) {
+    PrepareCookies(request()->url(),
+                   url::Origin(request_->first_party_for_cookies()));
+  }
+}
+
+void GenericURLRequestJob::PrepareCookies(const GURL& rewritten_url,
+                                          const url::Origin& site_for_cookies) {
+  net::CookieStore* cookie_store = request_->context()->cookie_store();
+  net::CookieOptions options;
+  options.set_include_httponly();
+
+  // See net::URLRequestHttpJob::AddCookieHeaderAndStart().
+  url::Origin requested_origin(rewritten_url);
+  if (net::registry_controlled_domains::SameDomainOrHost(
+          requested_origin, site_for_cookies,
+          net::registry_controlled_domains::INCLUDE_PRIVATE_REGISTRIES)) {
+    if (net::registry_controlled_domains::SameDomainOrHost(
+            requested_origin, request_->initiator(),
+            net::registry_controlled_domains::INCLUDE_PRIVATE_REGISTRIES)) {
+      options.set_same_site_cookie_mode(
+          net::CookieOptions::SameSiteCookieMode::INCLUDE_STRICT_AND_LAX);
+    } else if (IsMethodSafe(request_->method())) {
+      options.set_same_site_cookie_mode(
+          net::CookieOptions::SameSiteCookieMode::INCLUDE_LAX);
+    }
+  }
+
+  cookie_store->GetCookieListWithOptionsAsync(
+      rewritten_url, options,
+      base::Bind(&GenericURLRequestJob::OnCookiesAvailable,
+                 weak_factory_.GetWeakPtr(), rewritten_url));
+}
+
+void GenericURLRequestJob::OnCookiesAvailable(
+    const GURL& rewritten_url,
+    const net::CookieList& cookie_list) {
+  // TODO(alexclarke): Set user agent.
+  // Pass cookies, the referrer and any extra headers into the fetch request.
+  extra_request_headers_.SetHeader(
+      net::HttpRequestHeaders::kCookie,
+      net::CookieStore::BuildCookieLine(cookie_list));
+
+  extra_request_headers_.SetHeader(net::HttpRequestHeaders::kReferer,
+                                   request_->referrer());
+
+  // The resource may have been supplied in the request.
+  const HttpResponse* matched_resource =
+      delegate_->MaybeMatchResource(rewritten_url, extra_request_headers_);
+
+  if (matched_resource) {
+    OnFetchCompleteExtractHeaders(
+        matched_resource->final_url, matched_resource->http_response_code,
+        matched_resource->response_data, matched_resource->response_data_size);
+  } else {
+    url_fetcher_->StartFetch(rewritten_url, extra_request_headers_, this);
+  }
+}
+
+void GenericURLRequestJob::OnStartError(net::Error error) {
+  DispatchStartError(error);
+}
+
+void GenericURLRequestJob::OnFetchComplete(
+    const std::string& final_url,
+    int http_response_code,
+    scoped_refptr<net::HttpResponseHeaders> response_headers,
+    const char* body,
+    size_t body_size) {
+  http_response_code_ = http_response_code;
+  response_headers_ = response_headers;
+  body_ = body;
+  body_size_ = body_size;
+
+  DispatchHeadersComplete();
+
+  std::string mime_type;
+  GetMimeType(&mime_type);
+
+  delegate_->OnResourceLoadComplete(final_url, mime_type, http_response_code);
+}
+
+int GenericURLRequestJob::ReadRawData(net::IOBuffer* buf, int buf_size) {
+  // TODO(skyostil): Implement ranged fetches.
+  // TODO(skyostil): Once we have working tests, add coverage for all the cases

[Sami, 2016/08/19 11:54:00]

nit: We do have working tests so maybe reword this a bit :)

[alex clarke (OOO till 29th), 2016/08/19 12:48:57]

Done.

+  // below.
+  size_t bytes_available = body_size_ - read_offset_;
+  size_t bytes_to_copy =
+      std::min(static_cast<size_t>(buf_size), bytes_available);
+  if (bytes_to_copy) {
+    std::memcpy(buf->data(), &body_[read_offset_], bytes_to_copy);
+    read_offset_ += bytes_to_copy;
+  }
+  return bytes_to_copy;
+}
+
+int GenericURLRequestJob::GetResponseCode() const {
+  return http_response_code_;
+}
+
+void GenericURLRequestJob::GetResponseInfo(net::HttpResponseInfo* info) {
+  info->headers = response_headers_;
+}
+
+bool GenericURLRequestJob::GetMimeType(std::string* mime_type) const {
+  if (!response_headers_)
+    return false;
+  return response_headers_->GetMimeType(mime_type);
+}
+
+bool GenericURLRequestJob::GetCharset(std::string* charset) {
+  if (!response_headers_)
+    return false;
+  return response_headers_->GetCharset(charset);
+}
+
+}  // namespace headless