Google Drive API - 带有实体框架的自定义 IDataStore

Question

我实现了我的自定义IDataStore，以便我可以将最终用户令牌存储在我的数据库中，而不是默认实现，默认实现保存在文件系统中的 %AppData%。

public class GoogleIDataStore : IDataStore
{
    ...
    public Task<T> GetAsync<T>(string key)
    {
        TaskCompletionSource<T> tcs = new TaskCompletionSource<T>();
        var user = repository.GetUser(key.Replace("oauth_", ""));
        var credentials = repository.GetCredentials(user.UserId);
        if (key.StartsWith("oauth") || credentials == null)
        {
            tcs.SetResult(default(T));
        }
        else
        {
            var JsonData = Newtonsoft.Json.JsonConvert.SerializeObject(Map(credentials));                
            tcs.SetResult(NewtonsoftJsonSerializer.Instance.Deserialize<T>(JsonData));
        }
        return tcs.Task;
    }   
}

控制器

public async Task<ActionResult> AuthorizeDrive(CancellationToken cancellationToken)
{
    var result = await new AuthorizationCodeMvcApp(this, new GoogleAppFlowMetadata()).
            AuthorizeAsync(cancellationToken);
    if (result.Credential == null)
        return new RedirectResult(result.RedirectUri);
    var driveService = new DriveService(new BaseClientService.Initializer
    {
        HttpClientInitializer = result.Credential,
        ApplicationName = "My app"
    });
    //Example how to access drive files
    var listReq = driveService.Files.List();
    listReq.Fields = "items/title,items/id,items/createdDate,items/downloadUrl,items/exportLinks";
    var list = listReq.Execute();
    return RedirectToAction("Index", "Home");
}

重定向事件上出现问题。在第一次重定向之后，它工作正常。

我发现重定向事件有所不同。在重定向事件中，T不是令牌响应，而是字符串。此外，密钥以"oauth_"为前缀。

所以我假设我应该在重定向上返回不同的结果，但我不知道要返回什么。

我得到的错误是：Google.Apis.Auth.OAuth2.Responses.TokenResponseException：错误："状态无效"，描述："，Uri：">

谷歌源代码参考https://code.google.com/p/google-api-dotnet-client/source/browse/Src/GoogleApis.DotNet4/Apis/Util/Store/FileDataStore.cs?r=eb702f917c0e18fc960d077af132d0d83bcd6a88

https://code.google.com/p/google-api-dotnet-client/source/browse/Src/GoogleApis.Auth/OAuth2/Web/AuthWebUtility.cs?r=eb702f917c0e18fc960d077af132d0d83bcd6a88

感谢您的帮助

Answer 1

我不完全确定为什么你的不起作用，但这是我使用的代码的副本。 完整的类可以在这里找到 数据库数据存储.cs

/// <summary>
        /// Returns the stored value for the given key or <c>null</c> if the matching file (<see cref="GenerateStoredKey"/>
        /// in <see cref="FolderPath"/> doesn't exist.
        /// </summary>
        /// <typeparam name="T">The type to retrieve</typeparam>
        /// <param name="key">The key to retrieve from the data store</param>
        /// <returns>The stored object</returns>
        public Task<T> GetAsync<T>(string key)
        {
            //Key is the user string sent with AuthorizeAsync
            if (string.IsNullOrEmpty(key))
            {
                throw new ArgumentException("Key MUST have a value");
            }
            TaskCompletionSource<T> tcs = new TaskCompletionSource<T>();

            // Note: create a method for opening the connection.
            SqlConnection myConnection = new SqlConnection("user id=" + LoginName + ";" +
                                      @"password=" + PassWord + ";server=" + ServerName + ";" +
                                      "Trusted_Connection=yes;" +
                                      "database=" + DatabaseName + "; " +
                                      "connection timeout=30");
            myConnection.Open();
            // Try and find the Row in the DB.
            using (SqlCommand command = new SqlCommand("select RefreshToken from GoogleUser where UserName = @username;", myConnection))
            {
                command.Parameters.AddWithValue("@username", key);
                string RefreshToken = null;
                SqlDataReader myReader = command.ExecuteReader();
                while (myReader.Read())
                {
                    RefreshToken = myReader["RefreshToken"].ToString();
                }
                if (RefreshToken == null)
                {
                    // we don't have a record so we request it of the user.
                    tcs.SetResult(default(T));
                }
                else
                {
                    try
                    {
                        // we have it we use that.
                        tcs.SetResult(NewtonsoftJsonSerializer.Instance.Deserialize<T>(RefreshToken));
                    }
                    catch (Exception ex)
                    {
                        tcs.SetException(ex);
                    }
                }
            }
            return tcs.Task;
        }

Answer 2

API 在您的IDataStore中(至少(存储两个值。从空的 IDataStore 的角度来看，以下是授权过程的样子(注意哪些行设置值，哪些行获得值(：

Getting IDataStore value:  MyKey       <= null
Setting IDataStore value:  oauth_MyKey => "http://localhost..."
Setting IDataStore value:  MyKey       => {"access_token":"...
Getting IDataStore value:  oauth_MyKey <= "http://localhost..."
Getting IDataStore value:  MyKey       <= {"access_token":"...

首先，API 尝试查找存储的access_token，但数据存储中没有(仅返回 null(，API 启动授权过程。"oauth_..."key 是 API 在此过程中需要的一些状态信息，通常在检索之前设置(根据我的经验(。

但是，如果您的IDataStore从未收到带有"oauth_.."键的值，因此没有要返回的内容，只需返回null，API 应该在需要时创建一个新值。