René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"what's the purpose of line_allocated_event for redis?","articleBody":"Hello, thanks for all the resources you provided in the book, helping me tremendously to understand what a clean architecture could look like in python world. Just have a quick question about this line in end-to-end test:\r\n\r\n    **subscription = redis_client.subscribe_to(\"line_allocated\")**\r\n\r\nwhat's line_allocated channel needed for? I could see that the message is getting published to \"change_batch_quantity\" channel but we are subscribed to a different channel but somehow still able to read the messages that come from change_batch_quantity. I might be missing something easy to understand as i don't have a lot of experience with redis pubsub. I thought the channel names should have been same for them to exchange messages. Regardless of it, the tests pass so it seems like i'm missing something here. Thank you\r\n\r\n```\r\n@pytest.mark.usefixtures(\"postgres_db\")\r\n@pytest.mark.usefixtures(\"restart_api\")\r\n@pytest.mark.usefixtures(\"restart_redis_pubsub\")\r\ndef test_change_batch_quantity_leading_to_reallocation():\r\n    # start with two batches and an order allocated to one of them\r\n    orderid, sku = random_orderid(), random_sku()\r\n    earlier_batch, later_batch = random_batchref(\"old\"), random_batchref(\"newer\")\r\n    api_client.post_to_add_batch(earlier_batch, sku, qty=10, eta=\"2011-01-01\")\r\n    api_client.post_to_add_batch(later_batch, sku, qty=10, eta=\"2011-01-02\")\r\n    r = api_client.post_to_allocate(orderid, sku, 10)\r\n    assert r.ok\r\n    response = api_client.get_allocation(orderid)\r\n    assert response.json()[0][\"batchref\"] == earlier_batch\r\n\r\n    **subscription = redis_client.subscribe_to(\"line_allocated\")**\r\n\r\n    # change quantity on allocated batch so it's less than our order\r\n    redis_client.publish_message(\r\n        \"change_batch_quantity\",\r\n        {\"batchref\": earlier_batch, \"qty\": 5},\r\n    )\r\n\r\n    # wait until we see a message saying the order has been reallocated\r\n    messages = []\r\n    for attempt in Retrying(stop=stop_after_delay(3), reraise=True):\r\n        with attempt:\r\n            message = subscription.get_message(timeout=1)\r\n            if message:\r\n                messages.append(message)\r\n                print(messages)\r\n            data = json.loads(messages[-1][\"data\"])\r\n            assert data[\"orderid\"] == orderid\r\n            assert data[\"batchref\"] == later_batch\r\n```","author":{"url":"https://github.com/uguryiilmz","@type":"Person","name":"uguryiilmz"},"datePublished":"2023-05-12T19:44:31.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/70/code/issues/70"}