feat: Add parameters for Kubeflow pipeline engine (WIP) (#107)

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

docling_serve/datamodel/callback.py

@@ -0,0 +1,50 @@
+import enum
+from typing import Annotated, Literal
+
+from pydantic import BaseModel, Field
+
+
+class ProgressKind(str, enum.Enum):
+    SET_NUM_DOCS = "set_num_docs"
+    UPDATE_PROCESSED = "update_processed"
+
+
+class BaseProgress(BaseModel):
+    kind: ProgressKind
+
+
+class ProgressSetNumDocs(BaseProgress):
+    kind: Literal[ProgressKind.SET_NUM_DOCS] = ProgressKind.SET_NUM_DOCS
+
+    num_docs: int
+
+
+class SucceededDocsItem(BaseModel):
+    source: str
+
+
+class FailedDocsItem(BaseModel):
+    source: str
+    error: str
+
+
+class ProgressUpdateProcessed(BaseProgress):
+    kind: Literal[ProgressKind.UPDATE_PROCESSED] = ProgressKind.UPDATE_PROCESSED
+
+    num_processed: int
+    num_succeeded: int
+    num_failed: int
+
+    docs_succeeded: list[SucceededDocsItem]
+    docs_failed: list[FailedDocsItem]
+
+
+class ProgressCallbackRequest(BaseModel):
+    task_id: str
+    progress: Annotated[
+        ProgressSetNumDocs | ProgressUpdateProcessed, Field(discriminator="kind")
+    ]
+
+
+class ProgressCallbackResponse(BaseModel):
+    status: Literal["ack"] = "ack"