Add support for distilling arbitrary URLs in DOM Distiller Viewer.

components/dom_distiller/core/url_utils.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 "components/dom_distiller/core/url_utils.h"
+
+#include <string>
+
+#include "base/guid.h"
+#include "components/dom_distiller/core/url_constants.h"
+#include "net/base/url_util.h"
+#include "url/gurl.h"
+
+namespace dom_distiller {
+
+namespace url_utils {
+
+namespace {
+
+const char kDummyInternalUrlPrefix[] = "chrome-distiller-internal://dummy/";
+
+}  // namespace
+
+const GURL GetDistillerViewUrlFromEntryId(const std::string& scheme,
+                                          const std::string& entry_id) {
+  GURL url(scheme + "://" + base::GenerateGUID());

[nasko, 2014/02/27 22:40:44]

Do you always want to generate new GUID for each call to this function? It means
that for the same entry id, you will get different results for each call.

[nyquist, 2014/02/28 16:46:51]

Yes, that's the idea. If this will be run in an extension, they will then always
get separate origins. The idea is to move the logic for this into something that
contains a map of these, and maybe unique CSS styles, etc. going forward. Doing
this from the start makes sure that all of these distilled pages will have their
own origin.

+  return net::AppendOrReplaceQueryParameter(url, kEntryIdKey, entry_id);
+}
+
+const GURL GetDistillerViewUrlFromUrl(const std::string& scheme,
+                                      const GURL& view_url) {
+  GURL url(scheme + "://" + base::GenerateGUID());
+  return net::AppendOrReplaceQueryParameter(url, kUrlKey, view_url.spec());
+}
+
+std::string GetValueForKeyInUrlPathQuery(const std::string& path,
+                                         const std::string& key) {
+  // Tools for retrieving a value in a query only works with full GURLs, so
+  // using a dummy scheme and host to create a fake URL which can be parsed.
+  GURL dummy_url(kDummyInternalUrlPrefix + path);
+  std::string value;
+  net::GetValueForKeyInQuery(dummy_url, key, &value);
+  return value;
+}
+
+bool IsDistillableUrl(const GURL& url) {
+  return url.is_valid() && url.SchemeIsHTTPOrHTTPS();
+}
+
+}  // namespace url_utils
+
+}  // namespace dom_distiller