Functions triggers and bindings

Trigger starts, bindings connect

Every function has exactly one trigger. Bindings move data in or out without requiring full SDK plumbing. Not every service supports every direction, so choose the binding type the integration actually provides.

Build an HTTP API

@app.route(route="orders/{order_id}", methods=["POST"])
@app.service_bus_queue_output(
    arg_name="msg", queue_name="orders-out", connection="SB_CONN"
)
def submit(req: func.HttpRequest, msg: func.Out[str]):
    order_id = req.route_params["order_id"]
    msg.set(order_id)
    return func.HttpResponse("queued", status_code=202)

Route values are in req.route_params; query-string values are in req.params.

Know the HTTP authorization levels

Anonymous needs no Functions key. Function is the default and accepts a function or host key. Admin requires the master key. Keys can be sent in code or x-functions-key, and local Core Tools do not enforce them.

Move long work off the request

An HTTP-triggered function must answer within 230 seconds. For longer work, return 202 Accepted with a status location and queue the processing for another function.