Google Calendar V3

申請google calendar API V3

官方網址: https://developers.google.com/google-apps/calendar/v3/reference/

Google calendar v2版本快要關閉，所以開始研究v3版本，遇到很多困難，希望寫下相關文件有助於相關的朋友解決困難

選擇左方選單 Your First APPàConfigure Your APP

根據以上的做法，需要先至Google Developers Console 先建立project後，再點選APIs & auth建立新的 Client ID, 但是new Client ID的認證方式有以下, 請選擇其中一種

一、單人登入模式

會產生三個碼(ClientID, Client Secret, Redirect URIS) ，根據GOOGLE官方說法，它會採用Oauth2.0二皆段認證方式，原本v2版本需要(gmailAccount, password)即可針對此人的calendar進行CRUD事件控制，然而V3版本的應用程式，要求使用者同意存取權限後，才能進行使用者的Google Calendar 的CRUD控制。

※程式範例

UserCredential credential = GoogleWebAuthorizationBroker.AuthorizeAsync(                new ClientSecrets                {                    //請依照申請的client Ikey填寫                    ClientId = "xxxxxx-km3rffkv4qaj1ljva3aub8s95mig4ama.apps.googleusercontent.com",                                     ClientSecret = "fpJhDvGXxBCfMOdfgtN3Sceg",                },                new[] { CalendarService.Scope.Calendar },                "user",                CancellationToken.None).Result;                CalendarService _service = new CalendarService(new BaseClientService.Initializer()                 {                     HttpClientInitializer = credential,                     ApplicationName = "API Project",  //請依照的創建的ProjectID Name填寫                 });

為了讓通過認證的資料儲存下來，可使用FileDataStore 把資訊儲存本地端電腦，下次不需重新認證，如果有多人帳號，也可使用此方式儲存。

credential = GoogleWebAuthorizationBroker.AuthorizeAsync(                 new ClientSecrets                 {                     ClientId = "xxxxxxxxxxxxxxx.apps.googleusercontent.com",                     ClientSecret = "xxxxxxxx3mEz81u51Axlp",                 },                new[] { CalendarService.Scope.Calendar },                strUser, //gmail 帳號  CancellationToken.None, new FileDataStore("Calendar.Auth.Store") ).Result;

FileDataStore : 是將認證資料Token 和 Reflash Token資料以JSON格式，儲存電腦中

請參考:

https://developers.google.com/api-client-library/dotnet/guide/aaa_oauth

二、domain 認證模式

根據官方的說法，需要在同一domain下，只提供mail帳號,可以直接對此人的calendar 進行CRUD動作而不再取得登入者授權, 所以要開通Service Account

l   先申請公司domain 的gmail  ex: some@compute.com.tw (PS: 需要向DNS註冊)

l   再到Google Developers Console 新增Service Account 

產生一組金鑰和私鑰和ClientID, ServiceAccount

l   功能表中點選管理員: ps: 需要有管理員的權限才允許登入

l   選擇安全性(Security)à顯示更多àAdvanced Setting

l   右邊選單中àManage API Client access

Client Name: 輸入在Google Developers Console 申請service Account 的 client ID

One or More API Scopes : 輸入 https://www.googleapis.com/auth/calendar (google 稱為API scope)

點選 Authorize 即可加入寫入calendar的權限

 ※程式範例

var certificate = new X509Certificate2(@"Coooper-d3d1343328a5.p12", "notasecret", X509KeyStorageFlags.Exportable); //將私鑰憑證輸入   ServiceAccountCredential credential = new ServiceAccountCredential(new    ServiceAccountCredential.Initializer(serviceAccountEmail) //依申請ServiceAccount的mail 填入                 {                     Scopes =                         new[] { CalendarService.Scope.Calendar },                     User = strUserGmailAccount                 }.FromCertificate                 (certificate));                 BaseClientService.Initializer initializer = new                 BaseClientService.Initializer();                 initializer.HttpClientInitializer = credential;                 initializer.ApplicationName = "Coooper";                 calservice = new CalendarService(initializer);

※程式範例

public class googleCalendarTaken :IgoogleCalendarHelp     {         public CalendarService _service;                public googleCalendarTaken(string strGmailAccount)         {             startBuild(strGmailAccount);         }         public void startBuild(string strUser)         {                      UserCredential credential;             try             {                 credential = GoogleWebAuthorizationBroker.AuthorizeAsync(                 new ClientSecrets                 {                     ClientId = "xxxxx",                     ClientSecret = "xxxx",                 },                new[] { CalendarService.Scope.Calendar },                strUser, CancellationToken.None, new FileDataStore("Calendar.Auth.Store")).Result;                 BaseClientService.Initializer initializer = new BaseClientService.Initializer();                 initializer.HttpClientInitializer = credential;                 initializer.ApplicationName = "Cooper"; //申請API Project Name                                   _service = new CalendarService(initializer);             }             catch (Exception ex)             {                               var st = new StackTrace(ex, true);                 var frame = st.GetFrame(0);                 var line = frame.GetFileLineNumber();                 throw new Exception("startBuild 失敗"+line.ToString() +"行號 " + ex.Message+"行數:"+ strTestLine);             }         }         public bool addEvent(viewCalendar viewCalendarObj)         {             try             {                             Event eventGoogle = new Event()                 {                     Kind = "calendar#event",                     Id = viewCalendarObj.strEventID,                     Summary = viewCalendarObj.strSummary,                     Location = viewCalendarObj.strLocation,                     Description = viewCalendarObj.strDesc,                                        Start = new EventDateTime()                     {                         DateTime = viewCalendarObj.timeStart,                     },                     End = new EventDateTime()                     {                         DateTime = viewCalendarObj.timeEnd,                     },                                   };                 _service.Events.Insert(eventGoogle, "primary").Execute();                  Event googleEventObj = getEvent(viewCalendarObj.strEventID);                                if (googleEventObj != null)                 {                     return true;                 }                 else                 {                     return false;                 }             }             catch (Exception ex)             {                 throw new Exception("addEvent  新增事件失敗：" + ex.Message);             }         }         /// <summary>         /// 刪除google 行事曆事件         /// </summary>         /// <param name="strCalendarID">google 行事曆的名稱</param>         /// <param name="strEventID">google calendar's id</param>         public bool deleteEvent(string strEventID)         {             try             {                 _service.Events.Delete("primary", strEventID).Execute();                 return true;             }             catch (Exception ex)             {                 throw new Exception("deleteEvent 刪除失敗" + ex.Message);             }         }         /// <summary>         /// 更新行事曆         /// </summary>         /// <param name="strEventID"></param>         /// <param name="viewCalendarObj"></param>         /// <returns></returns>         public bool updateEvent(viewCalendar viewCalendarObj)         {             try             {                            // First retrieve the event from the API.                 Event googleEventObj = _service.Events.Get("primary", viewCalendarObj.strEventID).Execute();                 if (!string.IsNullOrEmpty(viewCalendarObj.strSummary))                     googleEventObj.Summary = viewCalendarObj.strSummary;                 if (!string.IsNullOrEmpty(viewCalendarObj.strLocation))                     googleEventObj.Location = viewCalendarObj.strLocation;                 if (!string.IsNullOrEmpty(viewCalendarObj.strDesc))                     googleEventObj.Description = viewCalendarObj.strDesc;                 if (viewCalendarObj.timeStart != null)                 {                     googleEventObj.Start = new EventDateTime()                     {                         DateTime = viewCalendarObj.timeStart                     };                 }                 if (viewCalendarObj.timeEnd != null)                 {                     googleEventObj.End = new EventDateTime()                     {                         DateTime = viewCalendarObj.timeEnd                     };                 }                 googleEventObj.Status = "confirmed"; //即使已刪除，也會回復原本狀態                                Event updatedEvent = _service.Events.Update(googleEventObj, "primary", googleEventObj.Id).Execute();                 //比對所有資料是否一致，才代表更改成功                 Event confirmEventObj = getEvent(viewCalendarObj.strEventID);                 if ((confirmEventObj.Start.DateTime == googleEventObj.Start.DateTime)                     && (confirmEventObj.End.DateTime == googleEventObj.End.DateTime)                     && (confirmEventObj.Summary == googleEventObj.Summary)                     && (confirmEventObj.Location == googleEventObj.Location)                     && (confirmEventObj.Description == googleEventObj.Description) )                 {                     return true;                 }else                 {                     return false;                 }                            }             catch (Exception ex)             {                 throw new Exception("updateEvent: 更新失敗　" + ex.Message);             }         }         public Event getEvent(string strEventID)         {             try             {                  Event eventObj= _service.Events.Get("primary", strEventID).Execute();                  return eventObj;             }             catch (Exception ex)             {                 return null;             }         }