🚀 feat(langflow): add support for extra fields in VectorStoreFrontendNode

✨ feat(template): add method to add fields to a template
The VectorStoreFrontendNode now supports adding extra fields to its template. The add_extra_fields method is called after the node is loaded and adds the weaviate_url field to the template if the node is of type Weaviate. The Template class now has a method to add fields to a template. This method is used by the VectorStoreFrontendNode to add the weaviate_url field to its template.

src/backend/langflow/interface/base.py

@@ -53,9 +53,8 @@ class LangChainTypeCreator(BaseModel, ABC):
         signature = self.get_signature(name)
         if signature is None:
             logger.error(f"Node {name} not loaded")
-            return None
-        if isinstance(signature, FrontendNode):
             return signature
+        if not isinstance(signature, FrontendNode):
             fields = [
                 TemplateField(
                     name=key,
@@ -74,9 +73,13 @@ class LangChainTypeCreator(BaseModel, ABC):
                 if key != "_type"
             ]
             template = Template(type_name=name, fields=fields)
-        return self.frontend_node_class(
+            signature = self.frontend_node_class(
                 template=template,
                 description=signature.get("description", ""),
                 base_classes=signature["base_classes"],
                 name=name,
             )
+
+        signature.add_extra_fields()
+
+        return signature

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

@@ -24,6 +24,9 @@ class FrontendNode(BaseModel):
             }
         }
 
+    def add_extra_fields(self) -> None:
+        pass
+
     @staticmethod
     def format_field(field: TemplateField, name: Optional[str] = None) -> None:
         """Formats a given field based on its attributes and value."""

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

@@ -5,6 +5,21 @@ from langflow.template.frontend_node.base import FrontendNode
 
 
 class VectorStoreFrontendNode(FrontendNode):
+    def add_extra_fields(self) -> None:
+        if self.template.type_name == "Weaviate":
+            extra_field = TemplateField(
+                name="weaviate_url",
+                field_type="str",
+                required=True,
+                placeholder="http://localhost:8080",
+                show=True,
+                advanced=False,
+                multiline=False,
+                value="http://localhost:8080",
+            )
+
+            self.template.add_field(extra_field)
+
     @staticmethod
     def format_field(field: TemplateField, name: Optional[str] = None) -> None:
         FrontendNode.format_field(field, name)

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

@@ -23,3 +23,6 @@ class Template(BaseModel):
         result = {field.name: field.to_dict() for field in self.fields}
         result["_type"] = self.type_name  # type: ignore
         return result
+
+    def add_field(self, field: TemplateField) -> None:
+        self.fields.append(field)