Backend: Added sign out functionality

backend/app.py

@@ -33,6 +33,10 @@ def generate_token():
     return generate_token()
   return token
 
+def get_token_from_request(request):
+    token_header = request.headers.get('Authorization')
+    return token_header[token_header.find('Bearer ') + 7:]
+
 def generate_response(response, status, headers={}):
     response.status_code = status
     response.headers = {**{
@@ -158,5 +162,14 @@ def sign_in():
         'message': message
         }), status)
 
+@app.route('/api/sign_out', methods=['GET'])
+def sign_out():
+    token = get_token_from_request(request)
+    db.clear_token(token)
+    return generate_response(jsonify({
+        'success': True,
+        'message': 'Sign out successful!'
+        }), 200)
+
 if __name__ == '__main__':
     app.run(debug=True)
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backend/database.py

@@ -31,7 +31,7 @@ class User(db.Model):
 # User schema
 class UserSchema(ma.Schema):
     class Meta:
-        fields = ('id', 'email', 'username', 'token')
+        fields = ('id', 'email', 'username')
 
 # Init user schema
 user_schema = UserSchema(strict=True)
@@ -97,4 +97,10 @@ def is_valid_username_password(username, password):
     return password != None and password == valid_password
 
 def get_tokens():
-    return [user.token for user in User.query.all()]
+    return [user.token for user in User.query.all()]
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+
+def clear_token(token):
+    user = User.query.filter_by(token=token).first()
+    user.token = None
+    db.session.commit()
+    return user
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