Initial commit of document-service

app/utils.py

@@ -0,0 +1,66 @@
+import uuid
+import magic
+from fastapi import HTTPException, UploadFile
+from app.config import settings
+from app.enums import DocumentType
+
+def generate_document_id() -> str:
+    """Generate UUID for document"""
+    return str(uuid.uuid4())
+
+def s3_path_prefix(org_id: str, document_id: str) -> str:
+    """Generate S3 path prefix for document operations"""
+    return f"documents/{org_id}/{document_id}/"
+
+def detect_content_type(file: UploadFile) -> str:
+    """Detect content type using python-magic"""
+    file.file.seek(0)
+    content = file.file.read(2048)
+    file.file.seek(0)
+
+    mime = magic.Magic(mime=True)
+    return mime.from_buffer(content)
+
+def detect_document_type(filename: str, content_type: str) -> DocumentType:
+    """Detect document type from filename and content type"""
+    # Try content type first
+    doc_type = DocumentType.from_mime_type(content_type)
+    if doc_type:
+        return doc_type
+
+    # Fall back to extension
+    return DocumentType.from_extension(filename)
+
+def get_file_size_limit(document_type: DocumentType) -> int:
+    """Get max file size for document type"""
+    limits = {
+        DocumentType.PDF: settings.max_file_size_pdf,
+        DocumentType.DOCX: settings.max_file_size_docx,
+        DocumentType.XLSX: settings.max_file_size_xlsx,
+        DocumentType.JPG: settings.max_file_size_jpg,
+        DocumentType.JPEG: settings.max_file_size_jpeg,
+        DocumentType.PNG: settings.max_file_size_png,
+        DocumentType.GIF: settings.max_file_size_gif,
+    }
+    return limits.get(document_type, settings.max_file_size_default)
+
+def validate_file_size(file_size: int, document_type: DocumentType) -> None:
+    """Validate file size against limits"""
+    max_size = get_file_size_limit(document_type)
+    if file_size > max_size:
+        raise HTTPException(
+            status_code=413,
+            detail=f"File size {file_size} exceeds maximum {max_size} for {document_type.value}"
+        )
+
+def document_s3_key(org_id: str, document_id: str, filename: str) -> str:
+    """Generate S3 key for document"""
+    return f"{s3_path_prefix(org_id, document_id)}{filename}"
+
+def sanitize_filename(filename: str) -> str:
+    """Sanitize filename for S3"""
+    # Remove path separators and special characters
+    filename = filename.replace("/", "_").replace("\\", "_")
+    # Keep only safe characters
+    safe_chars = set("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789.-_")
+    return "".join(c for c in filename if c in safe_chars)