Add Digital Asset Links verification for postMessage API

chrome/browser/android/digital_asset_links/digital_asset_links_handler.h

+// Copyright 2017 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 CHROME_BROWSER_ANDROID_DIGITAL_ASSET_LINKS_DIGITAL_ASSET_LINKS_HANDLER_H_
+#define CHROME_BROWSER_ANDROID_DIGITAL_ASSET_LINKS_DIGITAL_ASSET_LINKS_HANDLER_H_
+
+#include "net/url_request/url_fetcher.h"
+#include "net/url_request/url_fetcher_delegate.h"
+#include "net/url_request/url_request_context_getter.h"
+
+namespace base {
+class DictionaryValue;
+}
+
+namespace digital_asset_links {
+
+extern const char kDigitalAssetLinksCheckResponseKeyLinked[];
+
+typedef base::Callback<void(std::unique_ptr<base::DictionaryValue>)>
+    RelationshipCheckResultCallback;
+
+// A handler class for sending REST API requests to DigitalAssetLinks web
+// end point. See
+// https://developers.google.com/digital-asset-links/v1/getting-started
+// for details of usage and APIs. These APIs are used to verify declared
+// relationships between different asset types like web domains or Android apps.
+// The lifecycle of this handler will be governed by the owner.
+class DigitalAssetLinksHandler : public net::URLFetcherDelegate {
+ public:
+  explicit DigitalAssetLinksHandler(
+      const scoped_refptr<net::URLRequestContextGetter>& request_context);
+  ~DigitalAssetLinksHandler() override;
+
+  // Checks whether the given "relationship" has been declared by the target
+  // |web_domain| for the source Android app which is uniquely defined by the
+  // |package_name| and SHA256 |fingerprint| (a string with 32 hexadecimals
+  // with : in between) given. Any error in the string params
+  // here will result in a bad request and a nullptr response to the callback.
+  //
+  // Calling this multiple times on the same handler will cancel the previous
+  // checks.
+  // See
+  // https://developers.google.com/digital-asset-links/reference/rest/v1/assetlinks/check
+  // for details.
+  bool CheckDigitalAssetLinkRelationship(
+      RelationshipCheckResultCallback callback,
+      const std::string& web_domain,
+      const std::string& package_name,
+      const std::string& fingerprint,
+      const std::string& relationship);
+
+ private:
+  // net::URLFetcherDelegate:
+  void OnURLFetchComplete(const net::URLFetcher* source) override;
+
+  // Callbacks for the SafeJsonParser.
+  void OnJSONParseSucceeded(std::unique_ptr<base::Value> result);
+  void OnJSONParseFailed(const std::string& error_message);
+
+  scoped_refptr<net::URLRequestContextGetter> request_context_;
+
+  std::unique_ptr<net::URLFetcher> url_fetcher_;
+
+  // The per request callback for receiving a URLFetcher result. This gets
+  // reset every time we get a new CheckDigitalAssetLinkRelationship call.
+  RelationshipCheckResultCallback callback_;
+
+  base::WeakPtrFactory<DigitalAssetLinksHandler> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(DigitalAssetLinksHandler);
+};
+
+}  // namespace digital_asset_links
+
+#endif  // CHROME_BROWSER_ANDROID_DIGITAL_ASSET_LINKS_DIGITAL_ASSET_LINKS_HANDLER_H_