google支付回调验证

原文链接： https://my.oschina.net/lemonzone2010/blog/398736

Google支付问题

20150218，挂机的日本服务器出现google支付被刷单现象，虽然目前进行的修补，但是这个问题并没有完全从根源上解决。并且公司以前的GooglePlay支付也有不完善的地方，在SDK端给支付回调发送支付信息后，支付回调程序没有调用Google API进行订单验证。因此Google支付流程需要进行完善。

Google支付解决方案

上面的支付问题，Google有自己的解决方案，就是根据订单号去向Google API发送验证申请，Google API会返回订单相关信息。可以根据这个信息和SDK返回的信息进行对比验证。

对于申请Google账号之类的流程，相信运营已经很清楚了，但是使用Google API还需要使用Google Developer Console创建Web Application账户，而后获取到client_id、client_secret、refresh_token。具体流程见下面：

1. 登陆 Google Developer Console ，地址：https://code.google.com/apis/console/

2. 在APIs & auth 项中找到 Credentials ，点击创建一个auth2.0 的web 应用

其中4的地址一定是可用域名 + /oauth2callback

创建完后，可以获得，client_id, client_secret, redirect_url

3. 获取Authorization code

google中心在登陆状态，打开新页面输入如下地址：

https://accounts.google.com/o/oauth2/auth?scope=https://www.googleapis.com/auth/androidpublisher&response_type=code&access_type=offline&redirect_uri={REDIRECT_URIS}&client_id={CLIENT_ID}

将蓝色部分根据相应的值进行替换;

这时会提示你是否要授权，点击授权，url地址栏会自动跳转，之后会获得code例如：https://www.example.com/oauth2callback?code=4/CpVOd8CljO_gxTRE1M5jtwEFwf8gRD44vrmKNDi4GSS.kr-GHuseD-oZEnp6UADFXm0E0MD3FlAI

4. 利用code获取refresh_token，这里需要post请求

请求地址：https://accounts.google.com/o/oauth2/token

请求参数：code, client_id, client_secret, redirect_uri, grant_type

其中 grant_type 值为 authorization_code

第一次发起请求得到的JSON字符串如下所示，以后再请求将不再出现refresh_token(长令牌,一般不会失效),需要保存好refresh_token,可以存放到配置文件(或者写到数据库),以备后用。

expires_in是指access_token的时效，为3600秒

{

"access_token": "ya29.3gC2jw5vm77YPkylq0H5sPJeJJDHX93Kq8qZHRJaMlknwJ85595eMogL300XKDOEI7zIsdeFEPY6zg",

"token_type": "Bearer",

"expires_in": 3600,

"refresh_token": "1/FbQD448CdDPfDEDpCy4gj_m3WDr_M0U5WupquXL_o"

}

在获取到client_id、client_secret、refresh_token后，我们的支付回调程序就可以使用订单号去请求Google Api进行验证。

Google支付回调验证流程

通过上一步获取到client_id、client_secret、refresh_token之后，支付回调程序就可以调用google api进行支付验证。具体流程如下：

1. 获取access_token。

请求地址：https://accounts.google.com/o/oauth2/token

请求方式：post

请求参数：client_id, client_secret, refresh_toke, grant_type

grant_type 值固定为 refresh_token

返回：json

Using the refresh token

Each access token is only valid for a short time. Once the current access token expires, the server will need to use the refresh token to get a new one. To do this, send a POST request to https://accounts.google.com/o/oauth2/tokenwith the following fields set:

grant_type=refresh_token
client_id=<the client ID token created in the APIs Console>
client_secret=<the client secret corresponding to the client ID>
refresh_token=<the refresh token from the previous step>

A successful response will contain another access token:

{
  "access_token" : "ya29.AHES3ZQ_MbZCwac9TBWIbjW5ilJkXvLTeSl530Na2",
  "token_type" : "Bearer",
  "expires_in" : 3600,
}

The refresh token thus allows a web server continual access to the API without requiring an active login to a Google account.

2. 通过获得access_token 就可以请求谷歌的 API 接口，获得订单状态

在这里我所需要获取的是我在应用内给GooglePlay支付的购买信息，此类信息包含以下几个属性：（可参考Google Play Developer API下的Purchases.products）

A ProductPurchase resource indicates the status of a user's inapp product purchase.

请求接口:https://www.googleapis.com/androidpublisher/v2/applications/packageName/purchases/products/productId/tokens/purchaseToken?access_token=access_token


packageName	The package name of the application the inapp product was sold in (for example, 'com.some.thing').
productId	The inapp product SKU (for example, 'com.some.thing.inapp1').
purchaseToken	The token provided to the user's device when the inapp product was purchased. 就是订单中purchaseToken

返回数据

{
  "kind": "androidpublisher#productPurchase",
  "purchaseTimeMillis": long,
  "purchaseState": integer,
  "consumptionState": integer,
  "developerPayload": string
}

consumptionState	integer	The consumption state of the inapp product. Possible values are: 0:Yet to be consumed 1:Consumed
developerPayload	string	A developer-specified string that contains supplemental information about an order.
kind	string	This kind represents an inappPurchase object in the androidpublisher service.
purchaseState	integer	The purchase state of the order. Possible values are: 0:Purchased 1:Cancelled 我们就是依靠这个判断购买信息
purchaseTimeMillis	long	The time the product was purchased, in milliseconds since the epoch (Jan 1, 1970).

到此支付验证完成!

参考文档：

http://blog.csdn.net/hjun01/article/details/42032841

http://www.vimer.cn/2014/04/google%E6%94%AF%E4%BB%98%E6%8E%A5%E5%8F%A3%E8%A2%AB%E5%88%B7%E4%BB%A5%E5%8F%8A%E8%A7%A3%E5%86%B3%E6%96%B9%E6%A1%88.html

调用接口遇到的几个问题:

1. Access Not Configured.

{

"error": {

"errors": [

{

"domain": "usageLimits",

"reason": "accessNotConfigured",

"message": "Access Not Configured. The API(Google Play Android Developer API)is not enabled for you project.Please use Google Developers Console to update your configuration."

}

"code": 403,

"message": "Access Not Configured. The API(Google Play Android Developer API)is not enabled for you project.Please use Google Developers Console to update your configuration."

}

在这个页面: https://console.developers.google.com

Google Developer Console

1. "Google Developer Console" > "APIs & Auth" subcategory "APIs" > (api list) "Google Play Android Developer API". Set "STATUS" to "ON".

2. "APIs & auth" subcategory "Credentials" > "Create new Client ID". Choose "Service account" and create the id.

3. You should get a P12 key from the browser.

问题2: projectNotLinked

{
    "error": {
        "errors": [
            {
                "domain": "androidpublisher",
                "reason": "projectNotLinked",
                "message": "The project id used to call the Google Play Developer API has not been linked in the Google Play Developer Console."
            }
        ],
        "code": 403,
        "message": "The project id used to call the Google Play Developer API has not been linked in the Google Play Developer Console."
    }
}

在这个页设置关联:https://play.google.com/apps/publish/

Google Play Developer Console

1. "Google Play Developer Console" > "Settings" > subcategory "API access".

2. Make a link to your "Linked Project".

3. "Service Account" place maybe already showing ur "Service account" CLIENT ID which made "google developer console".