Minor refactor of _create_default_ce_client. Use raise from when auth…

…entication fails in Client.__init__.

src/judge0/__init__.py

@@ -1,26 +1,14 @@
 import os
 
 from .api import async_execute, execute, sync_execute, wait
-from .clients import (
-    ATDJudge0CE,
-    ATDJudge0ExtraCE,
-    Client,
-    RapidJudge0CE,
-    RapidJudge0ExtraCE,
-    SuluJudge0CE,
-    SuluJudge0ExtraCE,
-)
+from .clients import CE, Client, EXTRA_CE
 from .retry import MaxRetries, MaxWaitTime, RegularPeriodRetry
 from .submission import Submission
 
 __all__ = [
-    ATDJudge0CE,
-    ATDJudge0ExtraCE,
     Client,
-    RapidJudge0CE,
-    RapidJudge0ExtraCE,
-    SuluJudge0CE,
-    SuluJudge0ExtraCE,
+    *CE,
+    *EXTRA_CE,
     Submission,
     RegularPeriodRetry,
     MaxRetries,
@@ -40,19 +28,13 @@ def _create_default_ce_client():
     except:  # noqa: E722
         pass
 
-    rapid_api_key = os.getenv("JUDGE0_RAPID_API_KEY")
-    sulu_api_key = os.getenv("JUDGE0_SULU_API_KEY")
-    atd_api_key = os.getenv("JUDGE0_ATD_API_KEY")
-
-    if rapid_api_key is not None:
-        client = RapidJudge0CE(api_key=rapid_api_key)
-    elif sulu_api_key is not None:
-        client = SuluJudge0CE(api_key=sulu_api_key)
-    elif atd_api_key is not None:
-        client = ATDJudge0CE(api_key=atd_api_key)
-    else:
-        # TODO: Create SuluJudge0CE with default client.
-        client = None
+    client = None
+    for client_class in CE:
+        api_key = os.getenv(client_class.API_KEY_ENV)
+        if api_key is not None:
+            client = client_class(api_key)
+
+    # TODO: If client is none, instantiate the default client.
 
     globals()["judge0_default_client"] = client
 

src/judge0/clients.py

@@ -1,20 +1,21 @@
-from typing import Iterable, Optional, Union
+from typing import Iterable, Union
 
 import requests
 
-from .retry import RegularPeriodRetry, RetryMechanism
-
 from .submission import Submission
 
 
 class Client:
+    API_KEY_ENV = "JUDGE0_API_KEY"
+
     def __init__(self, endpoint, auth_headers) -> None:
         self.endpoint = endpoint
         self.auth_headers = auth_headers
+
         try:
             self.languages = {lang["id"]: lang for lang in self.get_languages()}
-        except Exception:
-            raise RuntimeError("Client authentication failed.")
+        except Exception as e:
+            raise RuntimeError("Client authentication failed.") from e
 
     def get_about(self) -> dict:
         r = requests.get(
@@ -172,6 +173,8 @@ def get_submissions(
 
 
 class ATD(Client):
+    API_KEY_ENV = "JUDGE0_ATD_API_KEY"
+
     def __init__(self, endpoint, host_header_value, api_key):
         self.api_key = api_key
         super().__init__(
@@ -323,6 +326,8 @@ def get_submissions(
 
 
 class Rapid(Client):
+    API_KEY_ENV = "JUDGE0_RAPID_API_KEY"
+
     def __init__(self, endpoint, host_header_value, api_key):
         self.api_key = api_key
         super().__init__(
@@ -359,6 +364,8 @@ def __init__(self, api_key):
 
 
 class Sulu(Client):
+    API_KEY_ENV = "JUDGE0_SULU_API_KEY"
+
     def __init__(self, endpoint, api_key):
         self.api_key = api_key
         super().__init__(endpoint, {"Authorization": f"Bearer {api_key}"})
@@ -376,3 +383,10 @@ class SuluJudge0ExtraCE(Sulu):
 
     def __init__(self, api_key):
         super().__init__(self.DEFAULT_ENDPOINT, api_key=api_key)
+
+
+DEFAULT_CE_CLIENT_CLASS = SuluJudge0CE
+DEFAULT_EXTRA_CE_CLASS = SuluJudge0ExtraCE
+
+CE = [RapidJudge0CE, SuluJudge0CE, ATDJudge0CE]
+EXTRA_CE = [RapidJudge0ExtraCE, SuluJudge0ExtraCE, ATDJudge0ExtraCE]