Provide an offline engine API (#1567)

python/sglang/api.py

@@ -33,13 +33,23 @@ def function(
 
 
 def Runtime(*args, **kwargs):
-    # Avoid importing unnecessary dependency
     os.environ["TF_CPP_MIN_LOG_LEVEL"] = "3"
+
+    # Avoid importing unnecessary dependency
     from sglang.srt.server import Runtime
 
     return Runtime(*args, **kwargs)
 
 
+def Engine(*args, **kwargs):
+    os.environ["TF_CPP_MIN_LOG_LEVEL"] = "3"
+
+    # Avoid importing unnecessary dependency
+    from sglang.srt.server import Engine
+
+    return Engine(*args, **kwargs)
+
+
 def set_default_backend(backend: BaseBackend):
     global_config.default_backend = backend