Batch Publish from a User Data Function
Publish multiple Business Events in a single User Data Function call by passing an array as the event data.
When to use this recipe
Use batch publishing from a UDF when your function processes a collection of items and each item should generate its own event — for example, processing an HTTP request that contains multiple inventory updates at once.
Batch publish with an array payload
The key difference from a single-event publish is that event_data is a list of dictionaries instead of a single dictionary:
import azure.functions as func
from fabric.functions import *
udf = UserDataFunctions()
@udf.connection(argName="businessEventsClient", alias="RetailInventory")
@udf.route(trigger=HttpTrigger())
def batch_publish(req: HttpRequest, businessEventsClient: FabricBusinessEventsClient):
from datetime import datetime, timezone
items = req.get_json() # expects a list of inventory items
event_data = [
{
"store_id": item["store_id"],
"product_id": item["product_id"],
"current_qty": item["current_qty"],
"threshold_qty": item["threshold_qty"],
"occurred_at": datetime.now(timezone.utc).isoformat()
}
for item in items
]
businessEventsClient.PublishEvent(
type="Retail.Inventory.LowStockThreshold",
event_data=event_data,
data_version="v1"
)
return HttpResponse(f"Published {len(event_data)} events", status_code=200)
Example request payload
[
{ "store_id": "STR-001", "product_id": "SKU-9821", "current_qty": 4, "threshold_qty": 10 },
{ "store_id": "STR-003", "product_id": "SKU-4432", "current_qty": 2, "threshold_qty": 15 },
{ "store_id": "STR-007", "product_id": "SKU-7751", "current_qty": 1, "threshold_qty": 5 }
]
Add error handling
@udf.connection(argName="businessEventsClient", alias="RetailInventory")
@udf.route(trigger=HttpTrigger())
def batch_publish(req: HttpRequest, businessEventsClient: FabricBusinessEventsClient):
from datetime import datetime, timezone
try:
items = req.get_json()
except ValueError:
return HttpResponse("Invalid JSON body", status_code=400)
if not isinstance(items, list) or len(items) == 0:
return HttpResponse("Request body must be a non-empty array", status_code=400)
event_data = [
{
"store_id": item["store_id"],
"product_id": item["product_id"],
"current_qty": item["current_qty"],
"threshold_qty": item["threshold_qty"],
"occurred_at": datetime.now(timezone.utc).isoformat()
}
for item in items
]
businessEventsClient.PublishEvent(
type="Retail.Inventory.LowStockThreshold",
event_data=event_data,
data_version="v1"
)
return HttpResponse(f"Published {len(event_data)} events", status_code=200)
Considerations
Each item in the array becomes an independent event. The platform delivers each one individually, with its own retry window.
Validate array size before publishing. Very large arrays may hit request size limits. Filter the input to only include items that actually need an event.