Execution sequence correct?

[mizamae]

I am trying to execute a group_send sequentially within a Django view. The synchronous function from the model that is being called from the view is:

def findNewDevice():
    from MQTT.constants import MQTT_TOPIC_AUTODISCOVER
    cache.set(key='scanning',value=True,timeout=10)
    
    from channels.layers import get_channel_layer
    channel_layer = get_channel_layer()
    from asgiref.sync import async_to_sync
    from MainAPP.consumers import SystemConsumer
    async_to_sync(channel_layer.group_send)("MainAPPSystem", {"type": "publish.ScanningStatus"})
    
    from time import sleep
    DEVICE.newDevice_FIFO=queue.Queue(maxsize=1)
    i=0
    while DEVICE.newDevice_FIFO.empty() and i<=5:
        SignalPublishMQTTTopic.send(sender='DEVICE',TOPIC=MQTT_TOPIC_AUTODISCOVER,VALUE=0,QOS=2)
        i=i+1
        async_to_sync(channel_layer.group_send)("MainAPPSystem", {"type": "publish.ScanningStatus"})
        sleep(1)

When I enter into this findNewDevice function, it reaches the line with:

async_to_sync(channel_layer.group_send)("MainAPPSystem", {"type": "publish.ScanningStatus"})

and it continues the execution without entering into the publish_ScanningStatus of the consumer.

class SystemConsumer(JsonWebsocketConsumer):
    groups = ["Broadcast","MainAPPSystem"]

    def connect(self):
        self.accept()
    
    def publish_ScanningStatus(self,event):
        from django.core.cache import cache
        scanning=cache.get(key='scanning',default=False)
        self.send_json({"action":"scanning_status",
                      "value":scanning,
                      })
        print("Published scanning status: " +scanning)

after it finishes (5 seconds), it then enters the publish_ScanningStatus of the consumer only once. I thought that by including async_to_sync into a function, it converted it into sequential code, so it should execute the function instantaneously; obviously I understood wrongly so is there anything I could do to get a sequential execution of the code??

What I would need to have is send the message to the group (to the client) so that I can indicate it that the system is scanning for new devices...

Thanks!!

[yedpodtrzitko]

Looks like there's nothing asynchronous in the method publish_ScanningStatus, so either you dont need async_to_sync or you forgot to add await there (presumably to self.send_json())?