Azure function in python triggered by blob storage

function_app.py

import csv
import hashlib
import logging
import requests
import time
import uuid

import azure.functions as func
import azurefunctions.extensions.bindings.blob as blob
app = func.FunctionApp(http_auth_level=func.AuthLevel.ANONYMOUS)

API_URL = "https://sandbox.api.service.nhs.uk/comms/v1/message-batches"
ROUTING_PLAN_ID = "b838b13c-f98c-4def-93f0-515d4e4f4ee1"
JSON_HEADERS = {
        "Content-type": "application/json",
        "Accept": "application/json",
    }


@app.blob_trigger(
    arg_name="client", path="dir1/dir2/blob", connection="AzureWebJobsStorage"
)
def blob_trigger(client: blob.BlobClient):
    logging.info("Triggering batch message from blob update")
    blob_content = client.download_blob.readall()
    batch_message(blob_content)


def batch_message(raw_data):
    fieldnames = ("nhs_number", "date_of_birth")

    reader = csv.DictReader(raw_data, fieldnames)
    api_messages = [api_message(row) for row in reader]

    body = api_body(api_messages)
    response = requests.post(API_URL, json=body, headers=JSON_HEADERS)
    logging.info(response.text)


def api_body(api_messages):
    return {
        "data": {
            "type": "MessageBatch",
            "attributes": {
                "messageBatchReference": reference_uuid(time.time()),
                "routingPlanId": ROUTING_PLAN_ID,
                "messages": api_messages,
            },
        }
    }


def api_message(message_data):
    return {
        "messageReference": reference_uuid(message_data["nhs_number"]),
        "recipient": {
            "nhsNumber": message_data["nhs_number"],
            "dateOfBirth": message_data["date_of_birth"],
        },
        "personalisation": {},
    }


def reference_uuid(val):
    return str(uuid.UUID(hashlib.md5(val.encode("utf-8")).hexdigest()))


# batch_message(open("test.csv", "r"))