Mongoose脚本执行drop()挂起，数据插入也失败求助

核心问题原因 #

脚本无限挂起的根本原因是：当执行到connection.once('connected', ...)时，数据库连接已经处于就绪状态（readyState=1），这个connected事件不会再触发，导致事件回调里的删除集合、插入数据等逻辑永远无法执行，脚本因此卡在原地。

修复方案 #

直接移除connection.once('connected', ...)的包裹逻辑——既然已经通过console.log(connection.readyState)确认连接就绪，无需再等待该事件。如果要兼容连接尚未完全建立的场景，可改用await connection.asPromise()确保连接完成。

修改后的完整脚本

const axios = require("axios");
const XLSX = require("xlsx");
const fs = require("fs");
const path = require("path");
const mongoose = require("mongoose");
const connection = require("../../../config/connection");
const MdProdCat = require("../../../models/MdProdCat");

(async () => {
  try {

    // Download the .xlsx file
    console.log("=== Commencing MD Product Category import...");
    console.log("Downloading .xlsx file...");
    const response = await axios.get(
      "https://assets.mydeal.com.au/content/marketplace/MyDeal_Product_Category_List.xlsx",
      { responseType: "arraybuffer" }
    );
    console.log("Saving .xlsx file...");

    // Save the file to the project directory
    console.log("Saving .xlsx file...");
    const xlsxFilePath = path.join(
      __dirname,
      "MyDeal_Product_Category_List.xlsx"
    );
    fs.writeFileSync(xlsxFilePath, Buffer.from(response.data));
    console.log("Saved .xlsx file");

    // Convert the .xlsx file to .csv format
    console.log("Converting .xlsx to .csv...");
    const workbook = XLSX.read(response.data, { type: "buffer" });
    const sheetNameList = workbook.SheetNames;
    const csvData = XLSX.utils.sheet_to_csv(workbook.Sheets[sheetNameList[0]]);
    console.log("Converted .xlsx to .csv");

    // Convert the CSV data to an array of JSON objects
    console.log("Converting .csv to JSON...");
    const rows = csvData.split("\n").slice(1); // skip the header row
    const json = rows
      .filter((line) => line.trim()) // skip empty rows
      .map((line) => {
        const [CategoryID, Breadcrumbs] = line.split(",");
        return { _id: parseInt(CategoryID), Breadcrumbs };
      });
    console.log("Converted .csv to JSON");

    // Check the connection to the database
    console.log("Connection state: ", connection.readyState);
    // 确保连接完全就绪（兼容连接尚未建立的场景）
    await connection.asPromise();

    // Drop the collection in case it already exists
    try {
      // Drop the collection
      console.log("Dropping collection if it already exists");
      await connection.dropCollection('mdprodcats');
      console.log("Collection dropped successfully");
    } catch (error) {
      if (error.message === 'ns not found') {
        // Ignore the error if the collection does not exist
        console.log('Collection does not exist. Continuing...');
      } else {
        // Throw any other errors
        throw error;
      }
    }

    // Insert the JSON data into the MongoDB collection
    console.log("Inserting data...");
    await MdProdCat.insertMany(json);
    console.log("Data inserted successfully");

    // Close the connection
    console.log("Closing connection...");
    await connection.close();
    console.log("Connection closed");
    console.log("=== Import completed successfully");

    process.exit();

  } catch (error) {
    console.error("An error occurred:", error);
    process.exit(1);
  }
})();

额外说明 #

• connection.asPromise()是Mongoose提供的方法，会等待连接成功建立或抛出连接失败错误，比监听connected事件更适配异步流程。
• 移除connection.once('connected', ...)后，所有数据库操作会直接在已连接的上下文执行，不会再出现挂起问题。

内容的提问来源于stack exchange，提问作者K the Bae