Node.js：为子对象添加公共属性并追加父级汇总字段

Got it, let's tackle this problem step by step. Here's how you can achieve exactly what you need in Node.js:

Step 1: Understand the Input Structure #

First, let's assume a sample products array that matches your described scenario (adjust this to match your actual data structure if needed):

const products = [
  {
    "2024-05-01": [
      { product_id: 1, total_quantity_sold: 5 },
      { product_id: 2, total_quantity_sold: 3 }
    ]
  },
  {
    "2024-05-02": [
      { product_id: 1, total_quantity_sold: 2 },
      { product_id: 2, total_quantity_sold: 4 }
    ]
  }
];

Step 2: Write the Processing Logic #

We'll use array methods like map and reduce to handle adding common properties and calculating the total quantity:

// Define your shared public property here (customize this to your needs)
const sharedProperty = { product_category: "general" };

// Process the products array
const processedData = products.map(dateEntry => {
  // Extract the date key and its associated product list
  const [dateKey, productList] = Object.entries(dateEntry)[0];
  
  // Add the public property to each product in the list
  const updatedProducts = productList.map(product => ({
    ...product,
    ...sharedProperty
  }));
  
  // Calculate the total quantity sold for this date
  const totalQuantity = updatedProducts.reduce((sum, item) => {
    return sum + item.total_quantity_sold;
  }, 0);
  
  // Return the final entry with date data and total
  return {
    [dateKey]: updatedProducts,
    total: totalQuantity
  };
});

console.log(processedData);

Step 3: Verify the Output #

Running the code above will produce this result, perfect for your chart data needs:

[
  {
    "2024-05-01": [
      { product_id: 1, total_quantity_sold: 5, product_category: "general" },
      { product_id: 2, total_quantity_sold: 3, product_category: "general" }
    ],
    total: 8
  },
  {
    "2024-05-02": [
      { product_id: 1, total_quantity_sold: 2, product_category: "general" },
      { product_id: 2, total_quantity_sold: 4, product_category: "general" }
    ],
    total: 6
  }
]

Key Notes #

• Customize the Shared Property: Replace product_category: "general" with whatever public attributes you need to add to child objects.
• Handle Edge Cases: If your products array might have entries with multiple date keys (unlikely per your description), swap Object.entries(dateEntry)[0] with a loop over all entries to process each key-value pair.
• Efficiency: This approach runs in O(n*m) time where n is the number of date entries and m is the number of products per date—ideal for most charting use cases.

内容的提问来源于stack exchange，提问作者Omair Nabiel