Fix admin CLI system variable commands (#14956)

## What

Fixes #12409.

Implements admin CLI support for:

- `list vars;`
- `show var <name-or-prefix>;`
- `set var <name> <value>;`

## Changes

- Wire Go CLI variable commands to the admin API.
- Support integer and quoted string values in `SET VAR`.
- Return variable rows as `data_type`, `name`, `setting_type`, and
`value`.
- Add exact-name lookup with prefix fallback for `SHOW VAR`.
- Validate values by stored data type: `string`, `integer`, `bool`, and
`json`.
- Keep the legacy Python admin CLI/server behavior aligned.
- Update admin CLI docs and add focused tests.

## Verification

- `go test -count=1 ./internal/cli`
- `python3.12 -m py_compile admin/server/services.py
admin/server/routes.py api/db/services/system_settings_service.py
admin/client/parser.py admin/client/ragflow_client.py`
- Python admin CLI parser smoke test for `SET VAR`, quoted values, `SHOW
VAR`, and `LIST VARS`.
- Attempted `./run_go_tests.sh`; local environment is missing native
tokenizer/linker artifacts:
  - `internal/cpp/cmake-build-release/librag_tokenizer_c_api.a`
  - `-lstdc++`

Co-authored-by: Jin Hai <haijin.chn@gmail.com>

admin/client/parser.py

@@ -264,7 +264,7 @@ generate_key: GENERATE KEY FOR USER quoted_string ";"
 list_keys: LIST KEYS OF quoted_string ";"
 drop_key: DROP KEY quoted_string OF quoted_string ";"
 
-set_variable: SET VAR identifier identifier ";"
+set_variable: SET VAR identifier variable_value ";"
 show_variable: SHOW VAR identifier ";"
 list_variables: LIST VARS ";"
 list_configs: LIST CONFIGS ";"
@@ -378,6 +378,7 @@ update_chunk: UPDATE CHUNK quoted_string OF DATASET quoted_string SET quoted_str
 identifier_list: identifier (COMMA identifier)*
 
 identifier: WORD
+variable_value: WORD | NUMBER | QUOTED_STRING
 quoted_string: QUOTED_STRING
 status: ON | WORD
 

admin/client/ragflow_client.py

@@ -43,6 +43,12 @@ def encrypt(input_string):
     return base64.b64encode(cipher_text).decode("utf-8")
 
 
+def _strip_tree_value(value):
+    if isinstance(value, Tree):
+        value = value.children[0]
+    return str(value).strip("'\"")
+
+
 class RAGFlowClient:
     def __init__(self, http_client: HttpClient, server_type: str):
         self.http_client = http_client
@@ -526,10 +532,8 @@ class RAGFlowClient:
         if self.server_type != "admin":
             print("This command is only allowed in ADMIN mode")
 
-        var_name_tree: Tree = command["var_name"]
-        var_name = var_name_tree.children[0].strip("'\"")
-        var_value_tree: Tree = command["var_value"]
-        var_value = var_value_tree.children[0].strip("'\"")
+        var_name = _strip_tree_value(command["var_name"])
+        var_value = _strip_tree_value(command["var_value"])
         response = self.http_client.request("PUT", "/admin/variables",
                                             json_body={"var_name": var_name, "var_value": var_value}, use_api_base=True,
                                             auth_kind="admin")
@@ -544,8 +548,7 @@ class RAGFlowClient:
         if self.server_type != "admin":
             print("This command is only allowed in ADMIN mode")
 
-        var_name_tree: Tree = command["var_name"]
-        var_name = var_name_tree.children[0].strip("'\"")
+        var_name = _strip_tree_value(command["var_name"])
         response = self.http_client.request(method="GET", path="/admin/variables", json_body={"var_name": var_name},
                                             use_api_base=True, auth_kind="admin")
         res_json = response.json()

admin/server/routes.py

@@ -421,7 +421,7 @@ def get_user_permission(user_name: str):
 def set_variable():
     try:
         data = request.get_json()
-        if not data and "var_name" not in data:
+        if not data or "var_name" not in data:
             return error_response("Var name is required", 400)
 
         if "var_value" not in data:
@@ -449,7 +449,7 @@ def get_variable():
 
         # get var
         data = request.get_json()
-        if not data and "var_name" not in data:
+        if not data or "var_name" not in data:
             return error_response("Var name is required", 400)
         var_name: str = data["var_name"]
         res = SettingsMgr.get_by_name(var_name)

admin/server/services.py

@@ -330,36 +330,65 @@ class ServiceMgr:
 
 
 class SettingsMgr:
+    @staticmethod
+    def _format_setting(setting):
+        return {
+            "data_type": setting.data_type,
+            "name": setting.name,
+            "setting_type": "config",
+            "value": setting.value,
+        }
+
+    @staticmethod
+    def _validate_value(name: str, data_type: str, value: str):
+        data_type = data_type.lower()
+        value = str(value)
+        if data_type == "string":
+            return
+        if data_type == "integer":
+            try:
+                int(value)
+            except ValueError:
+                raise AdminException(f"Invalid integer value for {name}: {value}")
+            return
+        if data_type in {"bool", "boolean"}:
+            if value not in {"true", "false"}:
+                raise AdminException(f"Invalid bool value for {name}: expected true or false")
+            return
+        if data_type == "json":
+            try:
+                json.loads(value)
+            except json.JSONDecodeError:
+                raise AdminException(f"Invalid JSON value for {name}")
+            return
+        raise AdminException(f"Unsupported data type for {name}: {data_type}")
+
+    @staticmethod
+    def _infer_data_type(name: str):
+        if name.startswith("sandbox."):
+            return "json"
+        if name.endswith(".enabled"):
+            return "bool"
+        return "string"
+
     @staticmethod
     def get_all():
-        settings = SystemSettingsService.get_all()
+        settings = SystemSettingsService.get_all(reverse=False, order_by="name")
         result = []
         for setting in settings:
-            result.append(
-                {
-                    "name": setting.name,
-                    "source": setting.source,
-                    "data_type": setting.data_type,
-                    "value": setting.value,
-                }
-            )
+            result.append(SettingsMgr._format_setting(setting))
         return result
 
     @staticmethod
     def get_by_name(name: str):
         settings = SystemSettingsService.get_by_name(name)
         if len(settings) == 0:
-            raise AdminException(f"Can't get setting: {name}")
+            settings = SystemSettingsService.get_by_name_prefix(name)
+            if len(settings) == 0:
+                raise AdminException(f"Can't get setting: {name}")
         result = []
         for setting in settings:
-            result.append(
-                {
-                    "name": setting.name,
-                    "source": setting.source,
-                    "data_type": setting.data_type,
-                    "value": setting.value,
-                }
-            )
+            result.append(SettingsMgr._format_setting(setting))
         return result
 
     @staticmethod
@@ -367,6 +396,7 @@ class SettingsMgr:
         settings = SystemSettingsService.get_by_name(name)
         if len(settings) == 1:
             setting = settings[0]
+            SettingsMgr._validate_value(name, setting.data_type, value)
             setting.value = value
             setting_dict = setting.to_dict()
             SystemSettingsService.update_by_name(name, setting_dict)
@@ -376,12 +406,8 @@ class SettingsMgr:
             # Create new setting if it doesn't exist
 
             # Determine data_type based on name and value
-            if name.startswith("sandbox."):
-                data_type = "json"
-            elif name.endswith(".enabled"):
-                data_type = "boolean"
-            else:
-                data_type = "string"
+            data_type = SettingsMgr._infer_data_type(name)
+            SettingsMgr._validate_value(name, data_type, value)
 
             new_setting = {
                 "name": name,