refactor(api): consolidate allowed extensions handling

- Unified allowed extensions into a single `DOCUMENT_EXTENSIONS` reference
- Adjusted checks and imports in controllers and services to use the new constant
- Enhanced text extraction to support additional file types (EPUB, EML, MSG)

api/constants/__init__.py

@@ -1,3 +1,5 @@
+from configs import dify_config
+
 HIDDEN_VALUE = "[__HIDDEN__]"
 UUID_NIL = "00000000-0000-0000-0000-000000000000"
 
@@ -13,9 +15,7 @@
 DOCUMENT_EXTENSIONS = ["txt", "markdown", "md", "pdf", "html", "htm", "xlsx", "xls", "docx", "csv"]
 DOCUMENT_EXTENSIONS.extend([ext.upper() for ext in DOCUMENT_EXTENSIONS])
 
-ALLOWED_EXTENSIONS = ["txt", "markdown", "md", "pdf", "html", "htm", "xlsx", "xls", "docx", "csv"]
-ALLOWED_EXTENSIONS.extend([ext.upper() for ext in ALLOWED_EXTENSIONS])
-
-UNSTRUCTURED_ALLOWED_EXTENSIONS = ["txt", "markdown", "md", "pdf", "html", "htm", "xlsx", "xls"]
-UNSTRUCTURED_ALLOWED_EXTENSIONS.extend(("docx", "csv", "eml", "msg", "pptx", "ppt", "xml", "epub"))
-UNSTRUCTURED_ALLOWED_EXTENSIONS.extend([ext.upper() for ext in UNSTRUCTURED_ALLOWED_EXTENSIONS])
+if dify_config.ETL_TYPE == "Unstructured":
+    DOCUMENT_EXTENSIONS = ["txt", "markdown", "md", "pdf", "html", "htm", "xlsx", "xls"]
+    DOCUMENT_EXTENSIONS.extend(("docx", "csv", "eml", "msg", "pptx", "ppt", "xml", "epub"))
+    DOCUMENT_EXTENSIONS.extend([ext.upper() for ext in DOCUMENT_EXTENSIONS])

api/controllers/console/datasets/file.py

@@ -6,7 +6,7 @@
 
 import services
 from configs import dify_config
-from constants import ALLOWED_EXTENSIONS, UNSTRUCTURED_ALLOWED_EXTENSIONS
+from constants import DOCUMENT_EXTENSIONS
 from controllers.console import api
 from controllers.console.datasets.error import (
     FileTooLargeError,
@@ -79,9 +79,7 @@ class FileSupportTypeApi(Resource):
     @login_required
     @account_initialization_required
     def get(self):
-        etl_type = dify_config.ETL_TYPE
-        allowed_extensions = UNSTRUCTURED_ALLOWED_EXTENSIONS if etl_type == "Unstructured" else ALLOWED_EXTENSIONS
-        return {"allowed_extensions": allowed_extensions}
+        return {"allowed_extensions": DOCUMENT_EXTENSIONS}
 
 
 class RemoteFileInfoApi(Resource):

api/core/workflow/nodes/document_extractor/document_extractor_node.py

@@ -5,6 +5,9 @@
 import docx
 import pandas as pd
 import pypdfium2
+from unstructured.partition.email import partition_email
+from unstructured.partition.epub import partition_epub
+from unstructured.partition.msg import partition_msg
 from unstructured.partition.ppt import partition_ppt
 from unstructured.partition.pptx import partition_pptx
 
@@ -96,6 +99,12 @@ def _extract_text(*, file_content: bytes, mime_type: str) -> str:
         return _extract_text_from_ppt(file_content)
     elif mime_type == "application/vnd.openxmlformats-officedocument.presentationml.presentation":
         return _extract_text_from_pptx(file_content)
+    elif mime_type == "application/epub+zip":
+        return _extract_text_from_epub(file_content)
+    elif mime_type == "message/rfc822":
+        return _extract_text_from_eml(file_content)
+    elif mime_type == "application/vnd.ms-outlook":
+        return _extract_text_from_msg(file_content)
     else:
         raise UnsupportedFileTypeError(f"Unsupported MIME type: {mime_type}")
 
@@ -210,3 +219,30 @@ def _extract_text_from_pptx(file_content: bytes) -> str:
         return "\n".join([getattr(element, "text", "") for element in elements])
     except Exception as e:
         raise TextExtractionError(f"Failed to extract text from PPTX: {str(e)}") from e
+
+
+def _extract_text_from_epub(file_content: bytes) -> str:
+    try:
+        with io.BytesIO(file_content) as file:
+            elements = partition_epub(file=file)
+        return "\n".join([str(element) for element in elements])
+    except Exception as e:
+        raise TextExtractionError(f"Failed to extract text from EPUB: {str(e)}") from e
+
+
+def _extract_text_from_eml(file_content: bytes) -> str:
+    try:
+        with io.BytesIO(file_content) as file:
+            elements = partition_email(file=file)
+        return "\n".join([str(element) for element in elements])
+    except Exception as e:
+        raise TextExtractionError(f"Failed to extract text from EML: {str(e)}") from e
+
+
+def _extract_text_from_msg(file_content: bytes) -> str:
+    try:
+        with io.BytesIO(file_content) as file:
+            elements = partition_msg(file=file)
+        return "\n".join([str(element) for element in elements])
+    except Exception as e:
+        raise TextExtractionError(f"Failed to extract text from MSG: {str(e)}") from e

api/services/file_service.py

@@ -10,10 +10,9 @@
 
 from configs import dify_config
 from constants import (
-    ALLOWED_EXTENSIONS,
     AUDIO_EXTENSIONS,
+    DOCUMENT_EXTENSIONS,
     IMAGE_EXTENSIONS,
-    UNSTRUCTURED_ALLOWED_EXTENSIONS,
     VIDEO_EXTENSIONS,
 )
 from core.file import helpers as file_helpers
@@ -147,9 +146,7 @@ def get_file_preview(file_id: str) -> str:
 
         # extract text from file
         extension = upload_file.extension
-        etl_type = dify_config.ETL_TYPE
-        allowed_extensions = UNSTRUCTURED_ALLOWED_EXTENSIONS if etl_type == "Unstructured" else ALLOWED_EXTENSIONS
-        if extension.lower() not in allowed_extensions:
+        if extension.lower() not in DOCUMENT_EXTENSIONS:
             raise UnsupportedFileTypeError()
 
         text = ExtractProcessor.load_from_upload_file(upload_file, return_text=True)