Google Android應用內購買「Content Delivery」如何正確提供內容？

Question

我目前正在嘗試編寫應用內購買代碼。我正在尋找文檔，信息和教程，介紹Google無法處理的一些內容的最佳做法。

我迄今所做的：

我有一個處理談論谷歌播放計費服務運行。此服務可以完成「示例」交易，我的應用程序收到該消息。

我想現在交付內容的設備。我覺得需要接下來會發生什麼：

1. 我的應用程序需要聯繫我的服務器，並顯示交易成功的一些證據。做一些證書搖手或一些這樣的廢話。

2. 然後，我將下載的內容和地方內容到數據庫中。我應該用某種設備的唯一加密來加密數據庫。

我期待着學習如何做上述2件事和其他需要做的事情。我想要一個合理數量的安全/加密。任何文檔/教程/示例項目都會很棒，我試着搜索這些東西，但沒有找到我想要的東西。

Answer 1

你必須做出一些改變，從樣品的計費服務的客戶端代碼。

首先，你應該打電話給你的服務器，以獲取將用於或者RestoreTransactions或進行購買的隨機數，把事情儘可能的安全。

讓我們跟隨發生了什麼。下面是得到由谷歌播放稱爲BillingReceiver：

/** 
* This is called when Android Market sends information about a purchase state 
* change. The signedData parameter is a plaintext JSON string that is 
* signed by the server with the developer's private key. The signature 
* for the signed data is passed in the signature parameter. 
* @param context the context 
* @param signedData the (unencrypted) JSON string 
* @param signature the signature for the signedData 
*/ 
private void purchaseStateChanged(Context context, String signedData, String signature) { 
    Intent intent = new Intent(Consts.ACTION_PURCHASE_STATE_CHANGED); 
    intent.setClass(context, BillingService.class); 
    intent.putExtra(Consts.INAPP_SIGNED_DATA, signedData); 
    intent.putExtra(Consts.INAPP_SIGNATURE, signature); 
    context.startService(intent); 
} 

如果你看看內BillingService.java handleCommand，它處理這個意圖：

/** 
* The {@link BillingReceiver} sends messages to this service using intents. 
* Each intent has an action and some extra arguments specific to that action. 
* @param intent the intent containing one of the supported actions 
* @param startId an identifier for the invocation instance of this service 
*/ 
public void handleCommand(Intent intent, int startId) { 
    String action = intent.getAction(); 
    if (Consts.DEBUG) { 
     Log.i(TAG, "handleCommand() action: " + action); 
    } 
    if (Consts.ACTION_CONFIRM_NOTIFICATION.equals(action)) { 
     String[] notifyIds = intent.getStringArrayExtra(Consts.NOTIFICATION_ID); 
     confirmNotifications(startId, notifyIds); 
    } else if (Consts.ACTION_GET_PURCHASE_INFORMATION.equals(action)) { 
     String notifyId = intent.getStringExtra(Consts.NOTIFICATION_ID); 
     getPurchaseInformation(startId, new String[] { notifyId }); 
    } else if (Consts.ACTION_PURCHASE_STATE_CHANGED.equals(action)) { 
     String signedData = intent.getStringExtra(Consts.INAPP_SIGNED_DATA); 
     String signature = intent.getStringExtra(Consts.INAPP_SIGNATURE); 
     purchaseStateChanged(startId, signedData, signature); 
    } else if (Consts.ACTION_RESPONSE_CODE.equals(action)) { 
     long requestId = intent.getLongExtra(Consts.INAPP_REQUEST_ID, -1); 
     int responseCodeIndex = intent.getIntExtra(Consts.INAPP_RESPONSE_CODE, 
       ResponseCode.RESULT_ERROR.ordinal()); 
     ResponseCode responseCode = ResponseCode.valueOf(responseCodeIndex); 
     checkResponseCode(requestId, responseCode); 
    } 
} 

這就要求thePurchaseStateChanged功能。此功能應該由您的服務器調用來爲您的內容傳送創建一個會話。來自Security.java的代碼應該移植到服務器端以驗證雲中的事務。

/** 
* Verifies that the data was signed with the given signature, and calls 
* {@link ResponseHandler#purchaseResponse(Context, PurchaseState, String, String, long)} 
* for each verified purchase. 
* @param startId an identifier for the invocation instance of this service 
* @param signedData the signed JSON string (signed, not encrypted) 
* @param signature the signature for the data, signed with the private key 
*/ 
private void purchaseStateChanged(int startId, String signedData, String signature) { 
    ArrayList<Security.VerifiedPurchase> purchases; 
    purchases = Security.verifyPurchase(signedData, signature); 
    if (purchases == null) { 
     return; 
    } 

    ArrayList<String> notifyList = new ArrayList<String>(); 
    for (VerifiedPurchase vp : purchases) { 
     if (vp.notificationId != null) { 
      notifyList.add(vp.notificationId); 
     } 
     ResponseHandler.purchaseResponse(this, vp.purchaseState, vp.productId, 
       vp.orderId, vp.purchaseTime, vp.developerPayload); 
    } 
    if (!notifyList.isEmpty()) { 
     String[] notifyIds = notifyList.toArray(new String[notifyList.size()]); 
     confirmNotifications(startId, notifyIds); 
    } 
} 

確保把你的公鑰在服務器端的移植Security.java文件。