feat: Added ability to use Client Credentials Grant (#39)

* feat:Added getting token using client credentials

- Added getting access token using client credentials grant.
  Use get_oauth_token() without params
- Minor logic refactoring

* fix:Fixed linter issue

README.md

@@ -116,7 +116,7 @@ casdoor-python-sdk support basic user operations, like:
 - `enforce(self, permission_model_name: str, sub: str, obj: str, act: str)`, check permission from model
 
 
-## Also. Resource Owner Password Credentials Grant
+## Resource Owner Password Credentials Grant
 
 If your application doesn't have a frontend that redirects users to Casdoor and you have Password Credentials Grant enabled, then you may get access token like this:
 
@@ -125,4 +125,16 @@ access_token = sdk.get_oauth_token(username=username, password=password)
 decoded_msg = sdk.parse_jwt_token(access_token)
 ```
 
-`decoded_msg` is the JSON data decoded from the `access_token`, which contains user info and other useful stuff.
+`decoded_msg` is the JSON data decoded from the `access_token`, which contains user info and other useful stuff.
+
+## Client Credentials Grant
+
+You can also use Client Credentials Grant when your application does not have a frontend.
+It is important to note that the AccessToken obtained in this way differs from other in that it corresponds to the application rather than to the user.
+
+```python
+access_token = sdk.get_oauth_token()
+decoded_msg = sdk.parse_jwt_token(access_token)
+```
+
+`decoded_msg` is the JSON data decoded from the `access_token`.

src/casdoor/async_main.py

@@ -88,19 +88,15 @@ async def get_oauth_token(
         """
         Request the Casdoor server to get access_token.
         Must be set code or username and password for grant type.
+        If nothing is set then client credentials grant will be used.
 
         :param code: the code that sent from Casdoor using redirect url
                      back to your server.
         :param username: Casdoor username
         :param password: username password
         :return: access token: str
         """
-        payload = self._get_payload_for_access_token_request(
-            code=code,
-            username=username,
-            password=password
-        )
-        response = await self._oath_token_request(payload)
+        response = await self.oauth_token_request(code, username, password)
         access_token = response.get("access_token")
 
         return access_token
@@ -122,8 +118,7 @@ def _get_payload_for_access_token_request(
                 password=password
             )
         else:
-            raise ValueError("Attributes for some grant type must be set"
-                             "(code or username and password)")
+            return self.__get_payload_for_client_credentials()
 
     def __get_payload_for_authorization_code(self, code: str) -> dict:
         """
@@ -153,24 +148,42 @@ def __get_payload_for_password_credentials(
             "password": password
         }
 
-    async def oauth_token_request(self, code: str) -> dict:
+    def __get_payload_for_client_credentials(self) -> dict:
+        """
+        Return payload for auth request with client credentials.
+        """
+        return {
+            "grant_type": "client_credentials",
+            "client_id": self.client_id,
+            "client_secret": self.client_secret,
+        }
+
+    async def oauth_token_request(
+            self,
+            code: Optional[str] = None,
+            username: Optional[str] = None,
+            password: Optional[str] = None
+    ) -> dict:
         """
         Request the Casdoor server to get access_token.
+        Must be set code or username and password for grant type.
+        If nothing is set then client credentials grant will be used.
         Returns full response as dict.
 
         :param code: the code that sent from Casdoor using redirect url
                      back to your server.
+        :param username: Casdoor username
+        :param password: username password
         :return: Response from Casdoor
         """
-        params = {
-            "grant_type": self.grant_type,
-            "client_id": self.client_id,
-            "client_secret": self.client_secret,
-            "code": code,
-        }
-        return await self._oath_token_request(payload=params)
+        params = self._get_payload_for_access_token_request(
+            code=code,
+            username=username,
+            password=password
+        )
+        return await self._oauth_token_request(payload=params)
 
-    async def _oath_token_request(self, payload: dict) -> dict:
+    async def _oauth_token_request(self, payload: dict) -> dict:
         """
         Request the Casdoor server to get access_token.
 

src/casdoor/main.py

@@ -80,21 +80,17 @@ def get_oauth_token(
             password: Optional[str] = None
     ) -> str:
         """
-        Request the Casdoor server to get access_token. Must be set code or
-        username and password for grant type.
+        Request the Casdoor server to get access_token.
+        Must be set code or username and password for grant type.
+        If nothing is set then client credentials grant will be used.
 
         :param code: the code that sent from Casdoor using redirect url back
                      to your server.
         :param username: casdoor username
         :param password: username password
         :return: access_token: str
         """
-        payload = self._get_payload_for_access_token_request(
-            code=code,
-            username=username,
-            password=password
-        )
-        response = self._oath_token_request(payload)
+        response = self.oauth_token_request(code, username, password)
         access_token = response.json().get("access_token")
 
         return access_token
@@ -116,8 +112,7 @@ def _get_payload_for_access_token_request(
                 password=password
             )
         else:
-            raise ValueError("Attributes for some grant type must be set"
-                             "(code or username and password)")
+            return self.__get_payload_for_client_credentials()
 
     def __get_payload_for_authorization_code(self, code: str) -> dict:
         """
@@ -147,23 +142,42 @@ def __get_payload_for_password_credentials(
             "password": password
         }
 
-    def oauth_token_request(self, code: str) -> requests.Response:
+    def __get_payload_for_client_credentials(self) -> dict:
         """
-        Request the Casdoor server to get access_token.
-
-        :param code: the code that sent from Casdoor using redirect
-                     url back to your server.
-        :return: Response from Casdoor
+        Return payload for auth request with client credentials.
         """
-        params = {
-            "grant_type": self.grant_type,
+        return {
+            "grant_type": "client_credentials",
             "client_id": self.client_id,
             "client_secret": self.client_secret,
-            "code": code,
         }
-        return self._oath_token_request(payload=params)
 
-    def _oath_token_request(self, payload: dict) -> requests.Response:
+    def oauth_token_request(
+            self,
+            code: Optional[str] = None,
+            username: Optional[str] = None,
+            password: Optional[str] = None
+    ) -> requests.Response:
+        """
+        Request the Casdoor server to get access_token.
+        Must be set code or username and password for grant type.
+        If nothing is set then client credentials grant will be used.
+        Returns full response as dict.
+
+        :param code: the code that sent from Casdoor using redirect url
+                     back to your server.
+        :param username: Casdoor username
+        :param password: username password
+        :return: Response from Casdoor
+        """
+        params = self._get_payload_for_access_token_request(
+            code=code,
+            username=username,
+            password=password
+        )
+        return self._oauth_token_request(payload=params)
+
+    def _oauth_token_request(self, payload: dict) -> requests.Response:
         """
         Request the Casdoor server to get access_token.
 

src/tests/test_async_oauth.py

@@ -47,15 +47,15 @@ def get_sdk():
         )
         return sdk
 
-    async def test__oath_token_request(self):
+    async def test__oauth_token_request(self):
         sdk = self.get_sdk()
         data = {
             "grant_type": sdk.grant_type,
             "client_id": sdk.client_id,
             "client_secret": sdk.client_secret,
             "code": self.code,
         }
-        response = await sdk._oath_token_request(payload=data)
+        response = await sdk._oauth_token_request(payload=data)
         self.assertIsInstance(response, dict)
 
     async def test__get_payload_for_authorization_code(self):
@@ -73,6 +73,11 @@ async def test__get_payload_for_password_credentials(self):
         )
         self.assertEqual("password", result.get("grant_type"))
 
+    async def test__get_payload_for_client_credentials(self):
+        sdk = self.get_sdk()
+        result = sdk._AsyncCasdoorSDK__get_payload_for_client_credentials()  # noqa: It's private method
+        self.assertEqual("client_credentials", result.get("grant_type"))
+
     async def test__get_payload_for_access_token_request_with_code(self):
         sdk = self.get_sdk()
         result = sdk._get_payload_for_access_token_request(code="test")
@@ -86,6 +91,11 @@ async def test__get_payload_for_access_token_request_with_cred(self):
         )
         self.assertEqual("password", result.get("grant_type"))
 
+    async def test_get_payload_for_access_token_request_with_client_cred(self):
+        sdk = self.get_sdk()
+        result = sdk._get_payload_for_access_token_request()
+        self.assertEqual("client_credentials", result.get("grant_type"))
+
     async def test_get_oauth_token_with_password(self):
         sdk = self.get_sdk()
         access_token = await sdk.get_oauth_token(
@@ -94,6 +104,11 @@ async def test_get_oauth_token_with_password(self):
         )
         self.assertIsInstance(access_token, str)
 
+    async def test_get_oauth_token_with_client_cred(self):
+        sdk = self.get_sdk()
+        access_token = await sdk.get_oauth_token()
+        self.assertIsInstance(access_token, str)
+
     async def test_get_oauth_token(self):
         sdk = self.get_sdk()
         access_token = await sdk.get_oauth_token(code=self.code)

src/tests/test_oauth.py

@@ -49,15 +49,15 @@ def get_sdk():
         )
         return sdk
 
-    def test__oath_token_request(self):
+    def test__oauth_token_request(self):
         sdk = self.get_sdk()
         data = {
             "grant_type": sdk.grant_type,
             "client_id": sdk.client_id,
             "client_secret": sdk.client_secret,
             "code": self.code,
         }
-        response = sdk._oath_token_request(payload=data)
+        response = sdk._oauth_token_request(payload=data)
         self.assertIsInstance(response, dict)
 
     def test__get_payload_for_authorization_code(self):
@@ -67,6 +67,11 @@ def test__get_payload_for_authorization_code(self):
         )
         self.assertEqual("authorization_code", result.get("grant_type"))
 
+    def test__get_payload_for_client_credentials(self):
+        sdk = self.get_sdk()
+        result = sdk._CasdoorSDK__get_payload_for_client_credentials()  # noqa: It's private method
+        self.assertEqual("client_credentials", result.get("grant_type"))
+
     def test__get_payload_for_password_credentials(self):
         sdk = self.get_sdk()
         result = sdk._CasdoorSDK__get_payload_for_password_credentials(  # noqa: It's private method
@@ -80,6 +85,11 @@ def test__get_payload_for_access_token_request_with_code(self):
         result = sdk._get_payload_for_access_token_request(code="test")
         self.assertEqual("authorization_code", result.get("grant_type"))
 
+    def test__get_payload_for_access_token_request_with_client_cred(self):
+        sdk = self.get_sdk()
+        result = sdk._get_payload_for_access_token_request()
+        self.assertEqual("client_credentials", result.get("grant_type"))
+
     def test__get_payload_for_access_token_request_with_cred(self):
         sdk = self.get_sdk()
         result = sdk._get_payload_for_access_token_request(
@@ -88,6 +98,11 @@ def test__get_payload_for_access_token_request_with_cred(self):
         )
         self.assertEqual("password", result.get("grant_type"))
 
+    def test_get_oauth_token_with_client_cred(self):
+        sdk = self.get_sdk()
+        access_token = sdk.get_oauth_token()
+        self.assertIsInstance(access_token, str)
+
     def test_get_oauth_token_with_code(self):
         sdk = self.get_sdk()
         access_token = sdk.get_oauth_token(code=self.code)