🔥 chore(template): delete unused files and imports

This commit removes unused files and imports from the template directory. The deleted files are base.py, fields.py, and nodes.py. The deleted imports are from langflow.template.constants. This improves the codebase by removing unnecessary code and reducing clutter.

✨ feat(frontend_node): add constants module
This commit adds a new module called constants to the frontend_node directory. The module contains constants used in the frontend_node module. The constants are FORCE_SHOW_FIELDS, DEFAULT_PROMPT, SYSTEM_PROMPT, and HUMAN_PROMPT. This improves the codebase by centralizing the constants in one module.

🐛 fix(frontend_node): use ast.literal_eval instead of eval
This commit fixes a security vulnerability by replacing the use of eval with ast.literal_eval in the UtilitiesFrontendNode class. The method converts a string representation of a list to an actual list. The use of eval is dangerous as it can execute arbitrary code. This improves the codebase by making it more secure.

src/backend/langflow/template/base.py

@@ -1 +0,0 @@
-

src/backend/langflow/template/frontend_node/base.py

@@ -3,7 +3,7 @@ from typing import List, Optional
 
 from pydantic import BaseModel
 
-from langflow.template.constants import FORCE_SHOW_FIELDS
+from langflow.template.frontend_node.constants import FORCE_SHOW_FIELDS
 from langflow.template.field.base import TemplateField
 from langflow.template.template.base import Template
 from langflow.utils import constants

src/backend/langflow/template/frontend_node/prompts.py

@@ -2,7 +2,11 @@ from typing import Optional
 
 from langchain.agents.mrkl import prompt
 
-from langflow.template.constants import DEFAULT_PROMPT, HUMAN_PROMPT, SYSTEM_PROMPT
+from langflow.template.frontend_node.constants import (
+    DEFAULT_PROMPT,
+    HUMAN_PROMPT,
+    SYSTEM_PROMPT,
+)
 from langflow.template.field.base import TemplateField
 from langflow.template.frontend_node.base import FrontendNode
 from langflow.template.template.base import Template

src/backend/langflow/template/frontend_node/utilities.py

@@ -1,3 +1,4 @@
+import ast
 import json
 from typing import Optional
 
@@ -12,7 +13,7 @@ class UtilitiesFrontendNode(FrontendNode):
         # field.field_type could be "Literal['news', 'search', 'places', 'images']
         # we need to convert it to a list
         if "Literal" in field.field_type:
-            field.options = eval(field.field_type.replace("Literal", ""))
+            field.options = ast.literal_eval(field.field_type.replace("Literal", ""))
             field.is_list = True
             field.field_type = "str"
 

src/backend/langflow/template/nodes.py

@@ -1 +0,0 @@
-

src/backend/langflow/utils/util.py

@@ -6,7 +6,7 @@ from typing import Dict, Optional
 
 from docstring_parser import parse  # type: ignore
 
-from langflow.template.constants import FORCE_SHOW_FIELDS
+from langflow.template.frontend_node.constants import FORCE_SHOW_FIELDS
 from langflow.utils import constants