Fix #18

As described in play-store-api code [1] recenlty google introduced a Time
To Live to each auth token, which caused them to expire in a matter of
seconds. Moreover, in order to retrieve a long-ttl token, a second auth
request now is needed, sending the Master Token returned from the first
request. This 'second round' request will return the actual authSubToken.

Another addition is that the code now return response's text for some
generic errors, in order to help debugging those problems.

gpapi/googleplay.py

@@ -50,6 +50,8 @@ def __init__(self, debug=False, device_codename='bacon'):
         self.gsfId = None
         self.debug = debug
         self.deviceBuilder = config.DeviceBuilder(device_codename)
+        # save last response text for error logging
+        self.lastResponseText = None
 
     def encrypt_password(self, login, passwd):
         """Encrypt the password using the google publickey, using
@@ -152,12 +154,14 @@ def login(self, email=None, password=None, gsfId=None, authSubToken=None):
             # AC2DM token
             params = self.deviceBuilder.getLoginParams(email, encryptedPass)
             response = requests.post(self.AUTHURL, data=params, verify=ssl_verify)
+            if self.debug:
+                self.lastResponseText = response.text
             data = response.text.split()
             params = {}
             for d in data:
                 if "=" not in d:
                     continue
-                k, v = d.split("=")[0:2]
+                k, v = d.split("=", 1)
                 params[k.strip().lower()] = v.strip()
             if "auth" in params:
                 ac2dmToken = params["auth"]
@@ -168,6 +172,8 @@ def login(self, email=None, password=None, gsfId=None, authSubToken=None):
                                      "to unlock, or setup an app-specific password")
                 raise LoginError("server says: " + params["error"])
             else:
+                if self.debug:
+                    print('Last response text: %s' % self.lastResponseText)
                 raise LoginError("Auth token not found.")
 
             self.gsfId = self.checkin(email, ac2dmToken)
@@ -187,31 +193,58 @@ def login(self, email=None, password=None, gsfId=None, authSubToken=None):
             raise LoginError('Either (email,pass) or (gsfId, authSubToken) is needed')
 
     def getAuthSubToken(self, email, passwd):
-        params = self.deviceBuilder.getAuthParams(email, passwd)
-        response = requests.post(self.AUTHURL, data=params, verify=ssl_verify)
+        requestParams = self.deviceBuilder.getAuthParams(email, passwd)
+        response = requests.post(self.AUTHURL, data=requestParams, verify=ssl_verify)
         data = response.text.split()
+        if self.debug:
+            self.lastResponseText = response.text
         params = {}
         for d in data:
             if "=" not in d:
                 continue
-            k, v = d.split("=")[0:2]
+            k, v = d.split("=", 1)
             params[k.strip().lower()] = v.strip()
-        if "auth" in params:
-            self.setAuthSubToken(params["auth"])
+        if "token" in params:
+            firstToken = params["token"]
+            if self.debug:
+                print('Master token: %s' % firstToken)
+            secondToken = self.getSecondRoundToken(requestParams, firstToken)
+            self.setAuthSubToken(secondToken)
         elif "error" in params:
             raise LoginError("server says: " + params["error"])
         else:
+            if self.debug:
+                print('Last response text: %s' % self.lastResponseText)
             raise LoginError("Auth token not found.")
 
-    def _check_response_integrity(self, apps):
-        """Like described in issue #18, after some time it seems
-        that google invalidates the token. And the strange thing is that when
-        sending requests with an invalid token, it won't throw an error but
-        it returns empty responses. This is a function used to check if the
-        content returned is valid (usually a docId field is always present)"""
-        if any([a['docId'] == '' for a in apps]):
-            raise LoginError('Unexpected behaviour, probably expired '
-                             'token')
+    def getSecondRoundToken(self, previousParams, firstToken):
+        previousParams['Token'] = firstToken
+        previousParams['service'] = 'androidmarket'
+        previousParams['check_email'] = '1'
+        previousParams['token_request_options'] = 'CAA4AQ=='
+        previousParams['system_partition'] = '1'
+        previousParams['_opt_is_called_from_account_manager'] = '1'
+        previousParams['google_play_services_version'] = '11518448'
+        previousParams.pop('Email')
+        previousParams.pop('EncryptedPasswd')
+        response = requests.post(self.AUTHURL, data=previousParams, verify=ssl_verify)
+        data = response.text.split()
+        if self.debug:
+            self.lastResponseText = response.text
+        params = {}
+        for d in data:
+            if "=" not in d:
+                continue
+            k, v = d.split("=", 1)
+            params[k.strip().lower()] = v.strip()
+        if "auth" in params:
+            return params["auth"]
+        elif "error" in params:
+            raise LoginError("server says: " + params["error"])
+        else:
+            if self.debug:
+                print('Last response text: %s' % self.lastResponseText)
+            raise LoginError("Auth token not found.")
 
     def executeRequestApi2(self, path, datapost=None,
                            post_content_type="application/x-www-form-urlencoded; charset=UTF-8"):
@@ -232,8 +265,12 @@ def executeRequestApi2(self, path, datapost=None,
                                     verify=ssl_verify,
                                     timeout=60)
 
+        if self.debug:
+            self.lastResponseText = response.text
         message = googleplay_pb2.ResponseWrapper.FromString(response.content)
         if message.commands.displayErrorMessage != "":
+            if self.debug:
+                print('Last response text: %s' % self.lastResponseText)
             raise RequestError(message.commands.displayErrorMessage)
 
         return message
@@ -270,6 +307,8 @@ def search(self, query, nb_result, offset=None):
             if len(response.payload.listResponse.cluster) == 0:
                 # strange behaviour, probably due to
                 # expired token
+                if self.debug:
+                    print('Last response text: %s' % self.lastResponseText)
                 raise LoginError('Unexpected behaviour, probably expired '
                                  'token')
             cluster = response.payload.listResponse.cluster[0]
@@ -293,7 +332,6 @@ def details(self, packageName):
         path = "details?doc=%s" % requests.utils.quote(packageName)
         data = self.executeRequestApi2(path)
         app = utils.fromDocToDictionary(data.payload.detailsResponse.docV2)
-        self._check_response_integrity([app])
         return app
 
     def bulkDetails(self, packageNames):
@@ -324,7 +362,6 @@ def bulkDetails(self, packageNames):
                 result.append(None)
             else:
                 appDetails = utils.fromDocToDictionary(entry.doc)
-                self._check_response_integrity([appDetails])
                 result.append(appDetails)
         return result
 
@@ -486,6 +523,8 @@ def delivery(self, packageName, versionCode, offerType=1,
                                 timeout=60)
         resObj = googleplay_pb2.ResponseWrapper.FromString(response.content)
         if resObj.commands.displayErrorMessage != "":
+            if self.debug:
+                print('Last response text: %s' % self.lastResponseText)
             raise RequestError(resObj.commands.displayErrorMessage)
         elif resObj.payload.deliveryResponse.appDeliveryData.downloadUrl == "":
             raise RequestError('App not purchased')
@@ -550,6 +589,8 @@ def download(self, packageName, versionCode, offerType=1,
 
         resObj = googleplay_pb2.ResponseWrapper.FromString(response.content)
         if resObj.commands.displayErrorMessage != "":
+            if self.debug:
+                print('Last response text: %s' % self.lastResponseText)
             raise RequestError(resObj.commands.displayErrorMessage)
         else:
             dlToken = resObj.payload.buyResponse.downloadToken