Move common PVer4 code into a V4ProtocolManagerUtil class.

components/safe_browsing_db/v4_protocol_manager_util.h

Index: components/safe_browsing_db/v4_protocol_manager_util.h
diff --git a/components/safe_browsing_db/v4_protocol_manager_util.h b/components/safe_browsing_db/v4_protocol_manager_util.h
new file mode 100644
index 0000000000000000000000000000000000000000..f4665f00587fc979ddbab8bb19c4530b87cd4287
--- /dev/null
+++ b/components/safe_browsing_db/v4_protocol_manager_util.h
@@ -0,0 +1,79 @@
+// 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.
+
+#ifndef COMPONENTS_SAFE_BROWSING_DB_V4_PROTOCOL_MANAGER_UTIL_H_
+#define COMPONENTS_SAFE_BROWSING_DB_V4_PROTOCOL_MANAGER_UTIL_H_
+
+// A class that implements the stateless methods used by the GetHashUpdate and
+// GetFullHash stubby calls made by Chrome using the SafeBrowsing V4 protocol.
+
+#include <string>
+
+#include "base/gtest_prod_util.h"
+#include "net/url_request/url_request_status.h"
+#include "url/gurl.h"
+
+namespace safe_browsing {
+
+// Config passed to the constructor of a V4 protocol manager.
+struct V4ProtocolConfig {
+  // The safe browsing client name sent in each request.
+  std::string client_name;
+
+  // Current product version sent in each request.
+  std::string version;
+
+  // The Google API key.
+  std::string key_param;
+};
+
+class V4ProtocolManagerUtil {
+ public:
+  // Record HTTP response code when there's no error in fetching an HTTP
+  // request, and the error code, when there is.
+  // |metric_name| is the name of the UMA metric to record the response code or
+  // error code against, |status| represents the status of the HTTP request, and
+  // |response code| represents the HTTP response code received from the server.
+  static void RecordHttpResponseOrErrorCode(const char* metric_name,
+                                            const net::URLRequestStatus& status,
+                                            int response_code);
+
+  // Generates a Pver4 request URL.
+  // |request_base64| is the serialized request protocol buffer encoded in
+  // base 64.
+  // |method_name| is the name of the method to call, as specified in the proto,
+  // |config| is an instance of V4ProtocolConfig that stores the client config.
+  static GURL GetRequestUrl(const std::string& request_base64,
+                            const std::string& method_name,
+                            const V4ProtocolConfig& config);
+
+  // Worker function for calculating the backoff times.
+  // |multiplier| is doubled for each consecutive error after the
+  // first, and |error_count| is incremented with each call.
+  static base::TimeDelta GetNextBackOffInterval(size_t* error_count,
+                                                size_t* multiplier);
+
+ private:
+  V4ProtocolManagerUtil() {};
+  FRIEND_TEST_ALL_PREFIXES(SafeBrowsingV4ProtocolManagerUtilTest,
+                           TestBackOffLogic);
+  FRIEND_TEST_ALL_PREFIXES(SafeBrowsingV4ProtocolManagerUtilTest,
+                           TestGetRequestUrl);
+
+  // Composes a URL using |prefix|, |method| (e.g.: encodedFullHashes).
+  // |request_base64|, |client_id|, |version| and |key_param|. |prefix|
+  // should contain the entire url prefix including scheme, host and path.
+  static std::string ComposeUrl(const std::string& prefix,
+                                const std::string& method,
+                                const std::string& request_base64,
+                                const std::string& client_id,
+                                const std::string& version,
+                                const std::string& key_param);
+
+  DISALLOW_COPY_AND_ASSIGN(V4ProtocolManagerUtil);
+};
+
+}  // namespace safe_browsing
+
+#endif  // COMPONENTS_SAFE_BROWSING_DB_V4_PROTOCOL_MANAGER_UTIL_H_