Fastai mobile push notifications using callbacks

fastai_push_notif_while_training.py

class NotificationCallback(Callback):
    """
        PyTorch callback for model training
    """
    def on_train_begin(self, metrics_names: StrList, **kwargs: Any) -> None:
        send_notification("Training has Begun ")

        
    def on_epoch_end(self,  epoch: int, smooth_loss: Tensor, last_metrics: MetricsList, **kwargs: Any) -> None:
        super().on_epoch_end(**kwargs)
        val_loss, accuracy = last_metrics[0], last_metrics[1]
        message = "epoch: " +str(epoch+1) + ": " +"train loss: " +f"{smooth_loss.item():.4f}" + " , " +" val loss: "+ f"{val_loss:.4f}" + " , " + " val accuracy: " +f"{accuracy:.4f}"
        send_notification(message)
        
    def on_train_end(self, metrics, **kwargs: Any) -> None:
        send_notification("Training finished ")
        
        
        
def send_notification(msg):
    """
        Send message to mobile using Pushover notifications.
        Calls Pushover API to do that.
        Pushover API docs: https://pushover.net/api
    """
    import requests
    from datetime import datetime

    url = "https://api.pushover.net/1/messages.json"
    data = {
        "user"  : "SECRET",
        "token" : "SECRET",
        "sound" : "cashregister" #head on to pushover docs to get list of many sounds on notif
    }
    data["message"] = msg
    data['message'] = data['message'] + "\n" + str(datetime.now())

    r =  requests.post(url = url, data = data)
    
    
    notif_cb = NotificationCallback()
    
    
    
    learn = cnn_learner(data, models.resnet50, metrics=[accuracy,error_rate] , model_dir="/tmp/model/",callbacks = [notif_cb])