feat: Async api (#60)

Signed-off-by: Michele Dolfi <dol@zurich.ibm.com>

docling_serve/datamodel/responses.py

@@ -0,0 +1,52 @@
+import enum
+from typing import Dict, List, Optional
+
+from pydantic import BaseModel
+
+from docling.datamodel.document import ConversionStatus, ErrorItem
+from docling.utils.profiling import ProfilingItem
+from docling_core.types.doc import DoclingDocument
+
+
+# Status
+class HealthCheckResponse(BaseModel):
+    status: str = "ok"
+
+
+class DocumentResponse(BaseModel):
+    filename: str
+    md_content: Optional[str] = None
+    json_content: Optional[DoclingDocument] = None
+    html_content: Optional[str] = None
+    text_content: Optional[str] = None
+    doctags_content: Optional[str] = None
+
+
+class ConvertDocumentResponse(BaseModel):
+    document: DocumentResponse
+    status: ConversionStatus
+    errors: List[ErrorItem] = []
+    processing_time: float
+    timings: Dict[str, ProfilingItem] = {}
+
+
+class ConvertDocumentErrorResponse(BaseModel):
+    status: ConversionStatus
+
+
+class TaskStatusResponse(BaseModel):
+    task_id: str
+    task_status: str
+    task_position: Optional[int] = None
+
+
+class MessageKind(str, enum.Enum):
+    CONNECTION = "connection"
+    UPDATE = "update"
+    ERROR = "error"
+
+
+class WebsocketMessage(BaseModel):
+    message: MessageKind
+    task: Optional[TaskStatusResponse] = None
+    error: Optional[str] = None