使Django信号在应用程序之间工作

如何解决使Django信号在应用程序之间工作

我有一个名为receive_printer的Django应用，当使用信号接收订单时，该应用应该打印订单。这里有两个应用程序：订单和 receipt_printer 。

但是，每当处理订单并充满电时，我都无法正常工作。为了简单起见，下面的示例只是向控制台输出了一些内容。如果我在“订单”应用中的models.py内部进行所有操作，则效果很好。

receipt_printer / apps.py

$ echo foo > foo              # making test files
$ echo bar > bar
$ mv -i --backup foo bar      # mving foo
mv: overwrite 'bar'? y        # -i caused this
$ cat bar                     
foo                           # mv caused this
$ cat bar~                    # --backup caused this
bar

receipt_printer / signals.py

from django.apps import AppConfig

class ReceiptPrinterConfig(AppConfig):
    name = 'receipt_printer'

    def ready(self):
        from . import signals

receipt_printer / 初始化 .py

from django.db import models
from saleor.order.models import Order
from django.db.models.signals import post_save

def order_fully_paid_signal(sender,instance,created,**kwargs):
    if instance.get_payment_status() == "fully-charged":
        print("This signal is working for fully paid order")
    else:
        print("This signal won't working for fully paid order")
post_save.connect(order_fully_paid_signal,sender=Order) 

更新，也尝试了以下方法-无效：

default_app_config = 'receipt_printer.apps.ReceiptPrinterConfig'

解决方法

不能完全确定这里是什么问题，但下面是我使用的post_save模式可以跨应用程序运行，而无需对apps.py或init.py进行任何更改：

from django.db.models.signals import post_save
from django.dispatch import receiver

@receiver(post_save,sender=<Model>,dispatch_uid='<model>_post_save')
def <model>_post_save(sender,instance,**kwargs):

    ...

,

我需要将以下行添加到我的订单应用程序的models.py底部：

function filter_woocommerce_add_to_cart_validation( $passed,$product_id,$quantity,$variation_id = null,$variations = null ) {
    // Get product object
    $product = wc_get_product( $product_id );
    
    // Flag
    $flag = false;
    
    // Is a WC product
    if ( is_a( $product,'WC_Product' ) ) {
        // Get the product attribute value
        $max_qty = $product->get_attribute( 'quantite_max' );
        
        // NOT empty
        if ( ! empty( $max_qty ) ) {
            // If new added quantity greater than max quantity
            if ( $quantity > $max_qty ) {
                $flag = true;
            // WC Cart NOT null & Cart is NOT empty
            } elseif ( ! is_null( WC()->cart ) && ! WC()->cart->is_empty() ) {
                // Get cart items quantities
                $cart_item_quantities = WC()->cart->get_cart_item_quantities();
                
                // Product quantity in cart
                $product_qty_in_cart = isset( $cart_item_quantities[ $product_id ] ) ? $cart_item_quantities[ $product_id ] : null;
                
                // New added quantity + product quantity in cart greater than max quantity
                if ( ( $quantity + $product_qty_in_cart ) > $max_qty ) {
                    $flag = true;
                }
            }
        }
    }
    
    // True
    if ( $flag ) {
        wc_add_notice( sprintf( __( 'Cant have more than %s x %s in cart','woocommerce' ),$max_qty,$product->get_name() ),'error' );
        $passed = false;
    }
    
    return $passed;
}
add_filter( 'woocommerce_add_to_cart_validation','filter_woocommerce_add_to_cart_validation',10,5 );