[Dice] Parse the Dice response header

components/signin/core/browser/dice_header_helper.cc

 // 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.
 
 #include "components/signin/core/browser/dice_header_helper.h"
 
+#include "base/strings/string_number_conversions.h"
 #include "components/signin/core/common/profile_management_switches.h"
 #include "google_apis/gaia/gaia_auth_util.h"
 #include "google_apis/gaia/gaia_urls.h"
-#include "url/gurl.h"
 
 namespace signin {
 
+namespace {
+
+const char kActionAttrName[] = "action";
+const char kAuthUserAttrName[] = "authuser";
+const char kAuthorizationCodeAttrName[] = "authorization_code";
+const char kEmailAttrName[] = "email";
+const char kIdAttrName[] = "id";
+
+// Determines the Dice action that has been passed from Gaia in the header.
+DiceAction GetDiceActionFromHeader(const std::string& value) {
+  if (value == "SIGNIN")
+    return DiceAction::SIGNIN;
+  else if (value == "SIGNOUT")
+    return DiceAction::SIGNOUT;
+  else if (value == "SINGLE_SESSION_SIGN_OUT")
+    return DiceAction::SINGLE_SESSION_SIGNOUT;
+  else
+    return DiceAction::NONE;
+}
+
+}  // namespace
+
+// static
+DiceResponseParams DiceHeaderHelper::BuildDiceResponseParams(
+    const std::string& header_value) {
+  DCHECK(!header_value.empty());
+  DiceResponseParams params;
+  ResponseHeaderDictionary header_dictionary =
+      ParseAccountConsistencyResponseHeader(header_value);
+  ResponseHeaderDictionary::const_iterator it = header_dictionary.begin();
+  for (; it != header_dictionary.end(); ++it) {
+    const std::string key_name(it->first);
+    const std::string value(it->second);
+    if (key_name == kActionAttrName) {
+      params.user_intention = GetDiceActionFromHeader(value);
+    } else if (key_name == kIdAttrName) {
+      params.obfuscated_gaia_id = value;
+    } else if (key_name == kEmailAttrName) {
+      params.email = value;
+    } else if (key_name == kAuthUserAttrName) {
+      bool parse_success = base::StringToInt(value, &params.session_index);
+      if (!parse_success)
+        params.session_index = -1;
+    } else if (key_name == kAuthorizationCodeAttrName) {
+      params.authorization_code = value;
+    } else {
+      DLOG(WARNING) << "Unexpected Gaia header attribute '" << key_name << "'.";
+    }
+  }
+
+  if (params.obfuscated_gaia_id.empty() || params.email.empty() ||
+      params.session_index == -1) {
+    DLOG(WARNING) << "Missing parameters for Dice header.";
+    params.user_intention = DiceAction::NONE;
+  }
+
+  if (params.user_intention == DiceAction::SIGNIN &&
+      params.authorization_code.empty()) {
+    DLOG(WARNING) << "Missing authorization code for Dice SIGNIN.";
+    params.user_intention = DiceAction::NONE;
+  }
+
+  return params;
+}
+
 bool DiceHeaderHelper::IsUrlEligibleForRequestHeader(const GURL& url) {
   if (switches::GetAccountConsistencyMethod() !=
       switches::AccountConsistencyMethod::kDice) {
     return false;
   }
   return gaia::IsGaiaSignonRealm(url.GetOrigin());
 }
 
 std::string DiceHeaderHelper::BuildRequestHeader(bool is_header_request,
                                                  const GURL& url,
                                                  const std::string& account_id,
                                                  int profile_mode_mask) {
   return "client_id=" + GaiaUrls::GetInstance()->oauth2_chrome_client_id();
 }
 
 }  // namespace signin