Add dynamic variable support to Assistant model and related components

- Introduce dynamic variable definitions in AssistantConfig and Assistant models, allowing for flexible prompt customization.
- Implement validation for dynamic variable names and types in the schema.
- Update backend services and routes to handle dynamic variables in assistant configurations and runtime processing.
- Enhance frontend components to support dynamic variable definitions, including a new editor for managing variables.
- Add tests to ensure proper functionality and validation of dynamic variables in various scenarios.

backend/tests/test_runtime_variables.py

@@ -0,0 +1,99 @@
+from __future__ import annotations
+
+import unittest
+
+from models import AssistantConfig
+from services.runtime_variables import (
+    DynamicVariableError,
+    DynamicVariableStore,
+    prepare_dynamic_config,
+    value_at_path,
+)
+
+
+class DynamicVariableTests(unittest.TestCase):
+    def test_defaults_client_values_and_system_values_are_merged(self):
+        cfg = AssistantConfig(
+            type="prompt",
+            runtimeMode="pipeline",
+            prompt="服务 {{user_name}} / {{tier}} / {{system__conversation_id}}",
+            greeting="您好 {{user_name}}",
+            dynamic_variable_definitions={
+                "user_name": {"type": "string", "required": True},
+                "tier": {"type": "string", "default": "普通"},
+            },
+        )
+        prepared = prepare_dynamic_config(
+            cfg, {"user_name": "王先生"}, assistant_id="asst_1"
+        )
+        store = DynamicVariableStore.from_config(prepared)
+        self.assertEqual(store.render(prepared.greeting), "您好 王先生")
+        self.assertIn("普通", store.render(prepared.prompt))
+        self.assertTrue(prepared.conversation_id.startswith("conv_"))
+        self.assertEqual(
+            prepared.dynamic_variables["system__conversation_id"],
+            prepared.conversation_id,
+        )
+
+    def test_realtime_prompt_supports_dynamic_variables(self):
+        cfg = AssistantConfig(
+            type="prompt",
+            runtimeMode="realtime",
+            prompt="请称呼用户为 {{user_name}}",
+            greeting="您好，{{user_name}}",
+            dynamic_variable_definitions={
+                "user_name": {"type": "string", "required": True}
+            },
+        )
+        prepared = prepare_dynamic_config(
+            cfg, {"user_name": "王先生"}, assistant_id="asst_realtime"
+        )
+        store = DynamicVariableStore.from_config(prepared)
+        self.assertEqual(store.render(prepared.greeting), "您好，王先生")
+        self.assertEqual(store.render(prepared.prompt), "请称呼用户为 王先生")
+
+    def test_client_cannot_set_reserved_or_wrong_typed_values(self):
+        cfg = AssistantConfig(
+            type="prompt",
+            runtimeMode="pipeline",
+            dynamic_variable_definitions={
+                "count": {"type": "number", "required": True}
+            },
+        )
+        with self.assertRaisesRegex(DynamicVariableError, "保留变量"):
+            prepare_dynamic_config(
+                cfg, {"system__agent_turns": 99}, assistant_id="asst_1"
+            )
+        with self.assertRaisesRegex(DynamicVariableError, "类型"):
+            prepare_dynamic_config(cfg, {"count": "1"}, assistant_id="asst_1")
+
+    def test_secret_is_header_only_and_expansion_is_single_pass(self):
+        store = DynamicVariableStore(
+            {"name": "{{secret__token}}"}, {"secret__token": "private"}
+        )
+        self.assertEqual(store.render("{{name}}"), "{{secret__token}}")
+        with self.assertRaisesRegex(DynamicVariableError, "只能用于 HTTP Header"):
+            store.render("{{secret__token}}")
+        self.assertEqual(
+            store.render("Bearer {{secret__token}}", allow_secrets=True),
+            "Bearer private",
+        )
+
+    def test_tool_assignment_and_system_history(self):
+        store = DynamicVariableStore(
+            {
+                "order_status": "unknown",
+                "system__agent_turns": 0,
+                "system__conversation_history": "",
+            }
+        )
+        store.assign("order_status", value_at_path({"order": {"status": "paid"}}, "order.status"))
+        store.record("user", "查订单")
+        store.record("agent", "已付款", completed_agent_turn=True)
+        self.assertEqual(store.values["order_status"], "paid")
+        self.assertEqual(store.values["system__agent_turns"], 1)
+        self.assertIn("查订单", store.values["system__conversation_history"])
+
+
+if __name__ == "__main__":
+    unittest.main()