Fix bug in requiring necessary packages (#123)

setup.py

@@ -25,7 +25,6 @@
 ]
 
 service_requires = [
-    "docstring_parser",
     "docker",
     "pymongo",
     "pymysql",
@@ -46,6 +45,7 @@
 
 # released requires
 minimal_requires = [
+    "docstring_parser",
     "loguru",
     "tiktoken",
     "Pillow",

src/agentscope/service/service_factory.py

@@ -98,6 +98,13 @@ def get(
         argsspec = inspect.getfullargspec(service_func)
 
         # Construct the mapping from arguments to their typings
+        if parse is None:
+            raise ImportError(
+                "Missing required package `docstring_parser`"
+                "Please install it by "
+                "`pip install docstring_parser`.",
+            )
+
         docstring = parse(service_func.__doc__)
 
         # Function description