chore(sdk): fix api backwards compatibility

fix api backwards compatibility

Author: ZXYmania

staxapp/api.py

@@ -11,6 +11,7 @@ class Api:
     def get_config(cls, config=None):
         if config is None:
             config = Config.GetDefaultConfig()
+            config.init()
         return config
 
     @classmethod

staxapp/config.py

@@ -29,8 +29,7 @@ class Config:
     _requests_auth = None
     _initialized = False
     base_url = None
-    _hostname = f"api.{STAX_REGION}"
-    hostname = None
+    hostname = f"api.{STAX_REGION}"
     org_id = None
     expiration = None
     load_live_schema = True
@@ -62,9 +61,8 @@ def get_api_config(cls, config_url):
         return config_response.json()
 
     def __init__(self, hostname=None, access_key=None, secret_key=None):
-        self.hostname = hostname
-        if self.hostname is None:
-            self.hostname = Config._hostname
+        if hostname is not None:
+            self.hostname = hostname
         self.access_key = access_key
         self.secret_key = secret_key
 
@@ -93,7 +91,7 @@ def branch(cls):
 
     @classmethod
     def schema_url(cls):
-        return f"https://{cls._hostname}/{cls.API_VERSION}/public/api-document"
+        return f"https://{cls.hostname}/{cls.API_VERSION}/public/api-document"
 
     @classmethod
     def get_auth_class(cls):

staxapp/contract.py

@@ -64,7 +64,7 @@ def default_swagger_template() -> dict:
                 "termsOfService": "/there_is_no_tos",
                 "contact": {"url": "https://stax.io"},
             },
-            servers=[{"url": f"https://{Config._hostname}"}],
+            servers=[{"url": f"https://{Config.hostname}"}],
             paths=dict(),
             components={
                 "securitySchemes": {