add cors

cloud-functions/python/functions/clearusers.py

@@ -15,6 +15,20 @@ def clear_users(request):
         Response object using `make_response`
         <https://flask.palletsprojects.com/en/1.1.x/api/#flask.make_response>.
     """
+    if request.method == 'OPTIONS':
+        headers = {
+            'Access-Control-Allow-Origin': '*',
+            'Access-Control-Allow-Methods': 'GET',
+            'Access-Control-Allow-Headers': 'Content-Type',
+            # 'Access-Control-Max-Age': '3600'
+        }
+
+        return ('', 204, headers)
+
+    headers = {
+        'Access-Control-Allow-Origin': '*'
+    }
+    
     key_path = os.getcwd() + '/hpos-preprod-firebase-adminsdk-d6jjt-ae42ad0f67.json'
     cred = credentials.Certificate(key_path)
     firebase_admin.initialize_app(cred)