fix: validate engine_id and normalize api_url for vNext support

Author: AndreyHirsa

src/lingodotdev/engine.py

@@ -23,6 +23,14 @@ class EngineConfig(BaseModel):
     batch_size: int = Field(default=25, ge=1, le=250)
     ideal_batch_item_size: int = Field(default=250, ge=1, le=2500)
 
+    @validator("engine_id", pre=True, always=True)
+    @classmethod
+    def validate_engine_id(cls, v: Optional[str]) -> Optional[str]:
+        if v is None:
+            return None
+        v = v.strip()
+        return v if v else None
+
     @validator("api_url", pre=True, always=True)
     @classmethod
     def validate_api_url(cls, v: Optional[str], values: Dict[str, Any]) -> str:
@@ -34,7 +42,7 @@ def validate_api_url(cls, v: Optional[str], values: Dict[str, Any]) -> str:
             return "https://engine.lingo.dev"
         if not v.startswith(("http://", "https://")):
             raise ValueError("API URL must be a valid HTTP/HTTPS URL")
-        return v
+        return v.rstrip("/")
 
 
 class LocalizationParams(BaseModel):

tests/test_engine.py

@@ -652,18 +652,51 @@ def setup_method(self):
         self.config = {"api_key": "test_api_key", "engine_id": "my-engine-id"}
         self.engine = LingoDotDevEngine(self.config)
 
+    def test_engine_id_empty_string_treated_as_none(self):
+        """Test that empty engine_id is treated as None"""
+        engine = LingoDotDevEngine({"api_key": "key", "engine_id": ""})
+        assert engine.config.engine_id is None
+        assert engine._is_vnext is False
+        assert engine.config.api_url == "https://engine.lingo.dev"
+
+    def test_engine_id_whitespace_treated_as_none(self):
+        """Test that whitespace-only engine_id is treated as None"""
+        engine = LingoDotDevEngine({"api_key": "key", "engine_id": "  "})
+        assert engine.config.engine_id is None
+        assert engine._is_vnext is False
+        assert engine.config.api_url == "https://engine.lingo.dev"
+
+    def test_engine_id_stripped(self):
+        """Test that engine_id is stripped of whitespace"""
+        engine = LingoDotDevEngine({"api_key": "key", "engine_id": " eng_123 "})
+        assert engine.config.engine_id == "eng_123"
+        assert engine._is_vnext is True
+
+    def test_api_url_trailing_slash_stripped(self):
+        """Test that trailing slash is stripped from api_url"""
+        engine = LingoDotDevEngine(
+            {
+                "api_key": "key",
+                "engine_id": "eng",
+                "api_url": "https://custom.api.com/",
+            }
+        )
+        assert engine.config.api_url == "https://custom.api.com"
+
     def test_engine_id_default_api_url(self):
         """Test that engine_id switches default api_url to api.lingo.dev"""
         assert self.engine.config.api_url == "https://api.lingo.dev"
         assert self.engine.config.engine_id == "my-engine-id"
 
     def test_engine_id_with_explicit_api_url(self):
         """Test that explicit api_url is preserved with engine_id"""
-        engine = LingoDotDevEngine({
-            "api_key": "key",
-            "engine_id": "eng",
-            "api_url": "https://custom.api.com",
-        })
+        engine = LingoDotDevEngine(
+            {
+                "api_key": "key",
+                "engine_id": "eng",
+                "api_url": "https://custom.api.com",
+            }
+        )
         assert engine.config.api_url == "https://custom.api.com"
 
     def test_is_vnext_true(self):
@@ -672,7 +705,9 @@ def test_is_vnext_true(self):
 
     def test_is_vnext_false_without_engine_id(self):
         """Test _is_vnext is False without engine_id"""
-        engine = LingoDotDevEngine({"api_key": "key", "api_url": "https://api.test.com"})
+        engine = LingoDotDevEngine(
+            {"api_key": "key", "api_url": "https://api.test.com"}
+        )
         assert engine._is_vnext is False
 
     def test_session_id_generated(self):
@@ -690,7 +725,9 @@ async def test_vnext_ensure_client_uses_x_api_key(self):
 
     async def test_classic_ensure_client_uses_bearer(self):
         """Test that classic engine uses Bearer auth header"""
-        engine = LingoDotDevEngine({"api_key": "test_key", "api_url": "https://api.test.com"})
+        engine = LingoDotDevEngine(
+            {"api_key": "test_key", "api_url": "https://api.test.com"}
+        )
         await engine._ensure_client()
         assert engine._client is not None
         assert engine._client.headers.get("authorization") == "Bearer test_key"
@@ -706,7 +743,11 @@ async def test_vnext_localize_chunk_url_and_body(self, mock_post):
         mock_post.return_value = mock_response
 
         await self.engine._localize_chunk(
-            "en", "es", {"data": {"key": "value"}, "reference": {"es": {"key": "ref"}}}, "wf", True
+            "en",
+            "es",
+            {"data": {"key": "value"}, "reference": {"es": {"key": "ref"}}},
+            "wf",
+            True,
         )
 
         call_args = mock_post.call_args