Add token validation logic and protected routes

app/accounts/__init__.py

@@ -49,3 +49,15 @@ def create_token(username, password):
         raise ValueError("Invalid credentials")
 
     return account.create_auth_token()
+
+
+def validate_token(token):
+    """
+    Validates token and returns associated account
+
+    :param token: auth token to validate
+    :type token: string
+    :returns created token
+    :rtype Account
+    """
+    return Account.validate_token(token)

app/accounts/models.py

@@ -77,20 +77,31 @@ class Account(db.Model):
         Generates the Auth Token
         :return: string
         """
-        try:
-            current_time = datetime.datetime.utcnow()
-            payload = {
-                'exp': current_time + datetime.timedelta(days=0, hours=1),
-                'iat': current_time,
-                'sub': self.id
-            }
-            return jwt.encode(
-                payload,
-                app.config.get('SECRET_KEY'),
-                algorithm='HS256'
-            ).decode('utf-8')
-        except Exception as e:
-            return e
+        current_time = datetime.datetime.utcnow()
+        payload = {
+            'exp': current_time + datetime.timedelta(days=0, hours=1),
+            'iat': current_time,
+            'sub': self.id
+        }
+        return jwt.encode(
+            payload,
+            app.config.get('SECRET_KEY'),
+            algorithm='HS256'
+        ).decode('utf-8')
+
+    @staticmethod
+    def validate_token(token):
+        """
+        Validates given Auth token
+        :rtype: Account
+        :return: Account associated with token
+        """
+        payload = jwt.decode(
+            token,
+            app.config.get('SECRET_KEY'),
+            algorithms=['HS256']
+        )
+        return Account.get(id=payload['sub'])
 
     def __repr__(self):
         return '<Account (name=%s, role=%s)>' % self.username, self.role

app/api/__init__.py

@@ -1,16 +1,45 @@
-from flask import Blueprint
-from flask_restful import Api
-from .resources.account import AccountResource
-from .resources.token import TokenResource
+from flask import Blueprint, request, g
+from flask_restful import Api, Resource, abort
+from functools import wraps
 from marshmallow import ValidationError
+from app.accounts import validate_token
 
 
 api_bp = Blueprint('api', __name__)
 api = Api(api_bp)
 
-# Add resources
-api.add_resource(AccountResource, '/v1/accounts')
-api.add_resource(TokenResource, '/v1/token')
+
+def protected(func):
+    @wraps(func)
+    def protected_function(*args, **kwargs):
+        try:
+            token = request.headers['Authorization'] or None
+
+            if not token:
+                abort(401, message='Unauthorized', status='error')
+
+            g.current_account = validate_token(token.replace("Bearer ", ""))
+            if not g.current_account:
+                abort(401, message='Unauthorized', status='error')
+        except Exception:
+            abort(401, message='Unauthorized', status='error')
+
+    return protected_function
+
+
+class ProtectedResource(Resource):
+    method_decorators = [protected]
+
+
+def add_resources():
+    from .resources.account import AccountResource
+    from .resources.token import TokenResource
+
+    api.add_resource(AccountResource, '/v1/accounts')
+    api.add_resource(TokenResource, '/v1/token')
+
+
+add_resources()
 
 
 @api_bp.errorhandler(ValidationError)

app/api/resources/account.py

@@ -3,6 +3,7 @@ from webargs import fields
 from webargs.flaskparser import use_args
 from flasgger import swag_from
 import app.accounts as accounts
+from app.api import protected
 
 
 class AccountResource(Resource):
@@ -28,6 +29,7 @@ class AccountResource(Resource):
         except ValueError:
             abort(422, message='Account already exists', status='error')
 
+    @protected
     @swag_from('swagger/get_account_spec.yaml')
     def get(self):
         return '', 200

app/api/resources/swagger/create_account_spec.yaml

@@ -19,6 +19,7 @@ parameters:
               - password
               - email
             $ref: '#/definitions/User'
+security: []
 responses:
   201:
     description: Successful creation

app/api/resources/swagger/create_token_spec.yaml

@@ -16,6 +16,7 @@ parameters:
         properties:
           user:
             $ref: '#/definitions/Credentials'
+security: []
 responses:
   200:
     description: Successful creation
@@ -33,4 +34,4 @@ responses:
   401:
     description: Bad credentials
     schema:
-      $ref: '#/definitions/Error'
+      $ref: '#/definitions/UnauthorizedError'

app/swagger/template.yaml

@@ -57,6 +57,19 @@ definitions:
       email:
         $ref: '#/definitions/email'
 
+  UnauthorizedError:
+    type: object
+    required:
+      - status
+      - message
+    properties:
+      status:
+        $ref: '#/definitions/status'
+        default: error
+      message:
+        $ref: '#/definitions/message'
+        default: Unauthorized
+
   Error:
     type: object
     required:
@@ -70,6 +83,27 @@ definitions:
         $ref: '#/definitions/message'
         default: Error message
 
+securityDefinitions:
+  Bearer:
+    type: apiKey
+    name: Authorization
+    in: header
+    description: |
+     For accessing the API a valid JWT token must be passed in all the queries in
+     the 'Authorization' header as Bearer token.
+
+
+     A valid JWT token is generated by the API and returned as answer of a call
+     to the route /login giving a valid user & password.
+
+
+     The following syntax must be used in the 'Authorization' header :
+
+         Bearer xxxxxx.yyyyyyy.zzzzzz
+
+security:
+  - Bearer: []
+
 info:
   description: Python (Flask) backend for IoT sysyem made for master's degree final project
   title: IoT Backend

config.py

@@ -33,3 +33,8 @@ MQTT_BROKER_PORT = 1883
 MQTT_USERNAME = 'user'
 MQTT_PASSWORD = 'secret'
 MQTT_REFRESH_TIME = 1.0  # refresh time in seconds
+
+# Flassger config
+SWAGGER = {
+    'uiversion': 3
+}