google-analytics-api Authentication Oauth2 C#

Example

Example uses the Google APIs Dotnet client library.

PM> Install-Package Google.Apis.AnalyticsReporting.v4

    /// <summary>
    /// This method requests Authentcation from a user using Oauth2.  
    /// Credentials are stored in System.Environment.SpecialFolder.Personal
    /// Documentation https://developers.google.com/accounts/docs/OAuth2
    /// </summary>
    /// <param name="clientSecretJson">Path to the client secret json file from Google Developers console.</param>
    /// <param name="userName">Identifying string for the user who is being authentcated.</param>
    /// <returns>DriveService used to make requests against the Drive API</returns>
    public static AnalyticsReportingService AuthenticateOauth(string clientSecretJson, string userName)
    {
        try
        {
            if (string.IsNullOrEmpty(userName))
                throw new Exception("userName is required.");
            if (string.IsNullOrEmpty(clientSecretJson))
                throw new Exception("clientSecretJson is required.");
            if (!File.Exists(clientSecretJson))
                throw new Exception("clientSecretJson file does not exist.");
            
            // These are the scopes of permissions you need.
            string[] scopes = new string[] { AnalyticsReportingService.Scope.AnalyticsReadonly };   // View your Google Analytics Data

            UserCredential credential;
            using (var stream = new FileStream(clientSecretJson, FileMode.Open, FileAccess.Read))
            {
                string credPath = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal);
                credPath = Path.Combine(credPath, ".credentials/", System.Reflection.Assembly.GetExecutingAssembly().GetName().Name);

                // Requesting Authentication or loading previously stored authentication for userName
                credential = GoogleWebAuthorizationBroker.AuthorizeAsync(GoogleClientSecrets.Load(stream).Secrets,
                                                                         scopes,
                                                                         userName,
                                                                         CancellationToken.None,
                                                                         new FileDataStore(credPath, true)).Result;
            }

            // Create Drive API service.
            return new AnalyticsReportingService(new BaseClientService.Initializer()
            {
                HttpClientInitializer = credential,
                ApplicationName = string.Format("{0} Authentication", System.Reflection.Assembly.GetExecutingAssembly().GetName().Name),
            });
        }
        catch (Exception ex)
        {
            Console.WriteLine("Create Oauth2 DriveService failed" + ex.Message);
            throw new Exception("CreateOauth2DriveFailed", ex);
        }
    }