feat: Allow using file variables directly in the LLM node and support more file types. (#10679)

Co-authored-by: Joel <iamjoel007@gmail.com>

api/core/file/file_manager.py

@@ -3,7 +3,12 @@ import base64
 from configs import dify_config
 from core.file import file_repository
 from core.helper import ssrf_proxy
-from core.model_runtime.entities import AudioPromptMessageContent, ImagePromptMessageContent, VideoPromptMessageContent
+from core.model_runtime.entities import (
+    AudioPromptMessageContent,
+    DocumentPromptMessageContent,
+    ImagePromptMessageContent,
+    VideoPromptMessageContent,
+)
 from extensions.ext_database import db
 from extensions.ext_storage import storage
 
@@ -29,35 +34,17 @@ def get_attr(*, file: File, attr: FileAttribute):
             return file.remote_url
         case FileAttribute.EXTENSION:
             return file.extension
-        case _:
-            raise ValueError(f"Invalid file attribute: {attr}")
 
 
 def to_prompt_message_content(
     f: File,
     /,
     *,
-    image_detail_config: ImagePromptMessageContent.DETAIL = ImagePromptMessageContent.DETAIL.LOW,
+    image_detail_config: ImagePromptMessageContent.DETAIL | None = None,
 ):
-    """
-    Convert a File object to an ImagePromptMessageContent or AudioPromptMessageContent object.
-
-    This function takes a File object and converts it to an appropriate PromptMessageContent
-    object, which can be used as a prompt for image or audio-based AI models.
-
-    Args:
-        f (File): The File object to convert.
-        detail (Optional[ImagePromptMessageContent.DETAIL]): The detail level for image prompts.
-            If not provided, defaults to ImagePromptMessageContent.DETAIL.LOW.
-
-    Returns:
-        Union[ImagePromptMessageContent, AudioPromptMessageContent]: An object containing the file data and detail level
-
-    Raises:
-        ValueError: If the file type is not supported or if required data is missing.
-    """
     match f.type:
         case FileType.IMAGE:
+            image_detail_config = image_detail_config or ImagePromptMessageContent.DETAIL.LOW
             if dify_config.MULTIMODAL_SEND_IMAGE_FORMAT == "url":
                 data = _to_url(f)
             else:
@@ -65,7 +52,7 @@ def to_prompt_message_content(
 
             return ImagePromptMessageContent(data=data, detail=image_detail_config)
         case FileType.AUDIO:
-            encoded_string = _file_to_encoded_string(f)
+            encoded_string = _get_encoded_string(f)
             if f.extension is None:
                 raise ValueError("Missing file extension")
             return AudioPromptMessageContent(data=encoded_string, format=f.extension.lstrip("."))
@@ -74,9 +61,20 @@ def to_prompt_message_content(
                 data = _to_url(f)
             else:
                 data = _to_base64_data_string(f)
+            if f.extension is None:
+                raise ValueError("Missing file extension")
             return VideoPromptMessageContent(data=data, format=f.extension.lstrip("."))
+        case FileType.DOCUMENT:
+            data = _get_encoded_string(f)
+            if f.mime_type is None:
+                raise ValueError("Missing file mime_type")
+            return DocumentPromptMessageContent(
+                encode_format="base64",
+                mime_type=f.mime_type,
+                data=data,
+            )
         case _:
-            raise ValueError("file type f.type is not supported")
+            raise ValueError(f"file type {f.type} is not supported")
 
 
 def download(f: File, /):
@@ -118,21 +116,16 @@ def _get_encoded_string(f: File, /):
         case FileTransferMethod.REMOTE_URL:
             response = ssrf_proxy.get(f.remote_url, follow_redirects=True)
             response.raise_for_status()
-            content = response.content
-            encoded_string = base64.b64encode(content).decode("utf-8")
-            return encoded_string
+            data = response.content
         case FileTransferMethod.LOCAL_FILE:
             upload_file = file_repository.get_upload_file(session=db.session(), file=f)
             data = _download_file_content(upload_file.key)
-            encoded_string = base64.b64encode(data).decode("utf-8")
-            return encoded_string
         case FileTransferMethod.TOOL_FILE:
             tool_file = file_repository.get_tool_file(session=db.session(), file=f)
             data = _download_file_content(tool_file.file_key)
-            encoded_string = base64.b64encode(data).decode("utf-8")
-            return encoded_string
-        case _:
-            raise ValueError(f"Unsupported transfer method: {f.transfer_method}")
+
+    encoded_string = base64.b64encode(data).decode("utf-8")
+    return encoded_string
 
 
 def _to_base64_data_string(f: File, /):
@@ -140,18 +133,6 @@ def _to_base64_data_string(f: File, /):
     return f"data:{f.mime_type};base64,{encoded_string}"
 
 
-def _file_to_encoded_string(f: File, /):
-    match f.type:
-        case FileType.IMAGE:
-            return _to_base64_data_string(f)
-        case FileType.VIDEO:
-            return _to_base64_data_string(f)
-        case FileType.AUDIO:
-            return _get_encoded_string(f)
-        case _:
-            raise ValueError(f"file type {f.type} is not supported")
-
-
 def _to_url(f: File, /):
     if f.transfer_method == FileTransferMethod.REMOTE_URL:
         if f.remote_url is None: