Issue 351: Reimplement OAuth2 - Step 2 (Auth PCL - only data types)

Src/GoogleApis.Auth/OAuth2/IAuthorizationCodeFlow.cs

Index: Src/GoogleApis.Auth/OAuth2/IAuthorizationCodeFlow.cs
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 b/Src/GoogleApis.Auth/OAuth2/IAuthorizationCodeFlow.cs
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 /*
 Copyright 2013 Google Inc
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at
 http://www.apache.org/licenses/LICENSE-2.0
 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
 */
 using System;
 using System.Threading;
 using System.Threading.Tasks;
 using Google.Apis.Auth.OAuth2.Responses;
 using Google.Apis.Auth.OAuth2.Requests;
 using Google.Apis.Util;
 using Google.Apis.Util.Store;
 namespace Google.Apis.Auth.OAuth2
 {
 /// <summary>OAuth 2.0 authorization code flow that manages and persists end-user credentials.</summary>
 public interface IAuthorizationCodeFlow : IDisposable
 {
 /// <summary>Gets the method for presenting the access token to the resource server.</summary>
 IAccessMethod AccessMethod { get; }
 /// <summary>Gets the clock.</summary>
 IClock Clock { get; }
 /// <summary>Gets the data store used to store the credentials.</summary>
 IDataStore DataStore { get; }
 /// <summary>Loads the user's token using the flow's <seealso cref="IDataStore"/>.</summary>
 /// <param name="userId">User identifier</param>
 /// <param name="taskCancellationToken">Cancellation token to cancel operation</param>
 /// <returns>Token response</returns>
 Task<TokenResponse> LoadToken(string userId, CancellationToken taskCancellationToken);
 /// <summary>Deletes the user's token using the flow's <seealso cref="IDataStore"/>.</summary>
 /// <param name="userId">User identifier</param>
 /// <param name="taskCancellationToken">Cancellation token to cancel operation</param>
 Task DeleteToken(string userId, CancellationToken taskCancellationToken);
 /// <summary>Creates an authorization code request with the specified redirect URI.</summary>
 AuthorizationCodeRequestUrl CreateAuthorizationCodeRequest(string redirectUri);
 /// <summary>Exchanges code with a token.</summary>
 /// <param name="userId">User identifier</param>
 /// <param name="code">Authorization code received from the authorization server</param>
 /// <param name="redirectUri">Redirect URI which is used in the token request</param>
 /// <param name="taskCancellationToken">Cancellation token to cancel operation</param>
 /// <returns>Token response which contains the access token</returns>
 Task<TokenResponse> ExchangeCodeForToken(string userId, string code, string redirectUri,
 CancellationToken taskCancellationToken);
 /// <summary>Refreshes an access token using a refresh token.</summary>
 /// <param name="userId">User identifier</param>
 /// <param name="refreshToken">Refresh token which is used to get a new access token</param>
 /// <param name="taskCancellationToken">Cancellation token to cancel operation</param>
 /// <returns>Token response which contains the access token and the input refresh token</returns>
 Task<TokenResponse> RefreshToken(string userId, string refreshToken, CancellationToken taskCancellationToken);
 }
 }