✨ (inputs/__init__.py): Add TextInput class to support text input type in langflow inputs

📝 (inputs/inputs.py): Add TextInput class with validation logic for different input types like Data, Message, and Text
📝 (schema/message.py): Add text_key attribute to Message class to specify the key for text data in the message object

src/backend/base/langflow/inputs/__init__.py

@@ -4,13 +4,14 @@ from .inputs import (
     DropdownInput,
     FileInput,
     FloatInput,
+    HandleInput,
     IntInput,
     MultilineInput,
     NestedDictInput,
     PromptInput,
     SecretStrInput,
     StrInput,
-    HandleInput,
+    TextInput,
 )
 
 __all__ = [
@@ -26,4 +27,5 @@ __all__ = [
     "PromptInput",
     "MultilineInput",
     "HandleInput",
+    "TextInput",
 ]

src/backend/base/langflow/inputs/inputs.py

@@ -1,8 +1,10 @@
-from typing import Callable, Optional, Union
+from typing import Any, Callable, Optional, Union
 
-from pydantic import Field, model_validator
+from pydantic import Field, field_validator, model_validator
 
 from langflow.inputs.validators import StrictBoolean
+from langflow.schema.data import Data
+from langflow.schema.message import Message
 
 from .input_mixin import (
     BaseInputMixin,
@@ -39,6 +41,30 @@ class StrInput(BaseInputMixin, ListableInputMixin, DatabaseLoadMixin):  # noqa:
     """Defines if the field will allow the user to open a text editor. Default is False."""
 
 
+class TextInput(StrInput):
+    input_types: list[str] = ["Data", "Message", "Text"]
+
+    @field_validator("value")
+    @classmethod
+    def validate_value(cls, v: Any, _info):
+        if isinstance(v, str):
+            return v
+        elif isinstance(v, Message):
+            return v.text
+        elif isinstance(v, Data):
+            if v.text_key in v.data:
+                return v.data[v.text_key]
+            else:
+                keys = ", ".join(v.data.keys())
+                input_name = _info.data["name"]
+                raise ValueError(
+                    f"The input to '{input_name}' must contain the key '{v.text_key}'."
+                    f"You can set `text_key` to one of the following keys: {keys} or set the value using another Component."
+                )
+        else:
+            raise ValueError(f"Invalid input type {type(v)}")
+
+
 class MultilineInput(BaseInputMixin):
     field_type: Optional[SerializableFieldTypes] = FieldTypes.TEXT
     multiline: StrictBoolean = True

src/backend/base/langflow/schema/message.py

@@ -17,6 +17,7 @@ def _timestamp_to_str(timestamp: datetime) -> str:
 class Message(Data):
     model_config = ConfigDict(arbitrary_types_allowed=True)
     # Helper class to deal with image data
+    text_key: str = "text"
     text: Optional[str | AsyncIterator | Iterator] = Field(default="")
     sender: str
     sender_name: str