无法在 Vue 3 单 Spa 应用程序中读取未定义的属性（读取“元”）

Question

我正在开发一个微前端项目，使用 vue 3 和 single-spa 5.9.3。 我试图将一个微前端 npm 包更新到最新版本，它可以正确构建，但会抛出此错误：

"TypeError: application '@myapp/my-module' died in status LOADING_SOURCE_CODE: Cannot read properties of undefined (reading 'meta')
    at autoPublicPath (http://localhost:9200/js/app.js:48439:32)
    at Object../node_modules/systemjs-webpack-interop/auto-public-path/2.js (http://localhost:9200/js/app.js:48418:1)
    at __webpack_require__ (http://localhost:9200/js/app.js:75668:33)
    at http://localhost:9200/js/app.js:76740:11
    at Object.<anonymous> (http://localhost:9200/js/app.js:76744:12)
    at Object.execute (https://cdn.jsdelivr.net/npm/[email protected]/dist/extras/amd.min.js:1:529)
    at i (https://cdn.jsdelivr.net/npm/[email protected]/dist/system.min.js:4:4539)
    at e (https://cdn.jsdelivr.net/npm/[email protected]/dist/system.min.js:4:5014)
    at https://cdn.jsdelivr.net/npm/[email protected]/dist/system.min.js:4:5019"

我的 '@myapp/my-module' package.json 依赖项如下所示：

  "dependencies": {
    "core-js": "^3.6.5",
    "axios": "^0.24.0",
    "object-path": "^0.11.8",
    "quasar": "^2.5.5",
    "single-spa-vue": "^2.1.0",
    "vue": "^3.2.29",
    "vue-i18n": "^9.1.6",
    "vue-inline-svg": "^3.1.0",
    "vue-router": "^4.0.0-0",
    "vue-axios": "^3.4.0",
    "vuex": "^4.0.0-0"
  },
  "devDependencies": {
    "@types/jest": "^27.4.1",
    "@typescript-eslint/eslint-plugin": "^5.4.0",
    "@typescript-eslint/parser": "^5.4.0",
    "@vue/cli-plugin-babel": "^5.0.3",
    "@vue/cli-plugin-e2e-cypress": "^5.0.3",
    "@vue/cli-plugin-eslint": "^5.0.3",
    "@vue/cli-plugin-router": "^5.0.3",
    "@vue/cli-plugin-typescript": "^5.0.3",
    "@vue/cli-plugin-unit-jest": "^5.0.3",
    "@vue/cli-plugin-vuex": "^5.0.3",
    "@vue/cli-service": "^5.0.3",
    "@vue/eslint-config-typescript": "^9.1.0",
    "@vue/test-utils": "^2.0.0-0",
    "eslint": "^7.32.0",
    "eslint-plugin-import": "^2.25.3",
    "eslint-plugin-vue": "^8.0.3",
    "jest-junit": "^13.0.0",
    "sass": "1.32.12",
    "sass-loader": "^10.1.0",
    "typescript": "~4.5.5",
    "vue-cli-plugin-quasar": "~4.0.4",
    "vue-cli-plugin-single-spa": "^3.3.0",
    "vue-jest": "^5.0.0-alpha.10"
  }

以及 single-spa 主项目“root- webpack.config”依赖项和 webpack 配置如下所示：

"devDependencies": {
    "@babel/core": "^7.14.6",
    "@babel/preset-env": "^7.14.7",
    "@types/systemjs": "^6.1.0",
    "babel-eslint": "^11.0.0-beta.2",
    "babel-loader": "^8.2.2",
    "bootstrap": "5.0.1",
    "concurrently": "^5.3.0",
    "copy-webpack-plugin": "^8.1.0",
    "css-loader": "^6.2.0",
    "eslint": "^6.8.0",
    "eslint-config-important-stuff": "^1.1.0",
    "eslint-config-prettier": "^6.15.0",
    "eslint-plugin-prettier": "^3.4.0",
    "html-webpack-plugin": "^5.3.2",
    "jest": "^25.4.0",
    "jest-cli": "^25.4.0",
    "jest-junit": "^13.0.0",
    "mini-css-extract-plugin": "^2.2.0",
    "prettier": "^2.3.2",
    "pretty-quick": "^2.0.2",
    "sass": "^1.38.0",
    "sass-loader": "^12.1.0",
    "serve": "^12.0.0",
    "webpack": "^5.51.0",
    "webpack-cli": "^4.8.0",
    "webpack-config-single-spa": "^5.0.0",
    "webpack-dev-server": "^4.0.0",
    "webpack-merge": "^5.8.0"
  },
  "dependencies": {
    "loadash": "^1.0.0",
    "single-spa": "^5.9.3"
  },

webpack.config.js：

const { merge } = require("webpack-merge");
const singleSpaDefaults = require("webpack-config-single-spa");
const HtmlWebpackPlugin = require("html-webpack-plugin");
const MiniCssExtractPlugin = require("mini-css-extract-plugin");
const CopyWebpackPlugin = require("copy-webpack-plugin");

module.exports = (webpackConfigEnv, argv) => {
  const orgName = "myapp";
  const defaultConfig = singleSpaDefaults({
    orgName,
    projectName: "root-config",
    webpackConfigEnv,
    argv,
    disableHtmlGeneration: true,
  });

  return merge(defaultConfig, {
    plugins: [
      new HtmlWebpackPlugin({
        inject: false,
        template: "src/index.ejs",
        templateParameters: {
          isLocal: webpackConfigEnv && webpackConfigEnv.isLocal,
          orgName,
        },
      }),
      new MiniCssExtractPlugin({
        filename: "css/style.css",
      }),
      new CopyWebpackPlugin({
        patterns: [
          {
            from: "./src/assets",
            to: "./assets",
          },
          {
            from: "./src/config",
            to: "./config",
          },
          {
            from:"favicon.ico",
            to: "favicon.ico",
          },
          {
            from:"staticwebapp.config.json",
            to:"staticwebapp.config.json"
          }
        ],
      }),
    ],
    module: {
      rules: [
        {
          test: /\.s[ac]ss$/i,
          use: [
            MiniCssExtractPlugin.loader,
            "css-loader",
            {
              loader: "sass-loader",
              options: {
                implementation: require("sass"),               
              },
            },
          ],
        },
      ],
    },
    externals: ["single-spa", "vue", "vue-router", "vuex", /^@myapp\/.+$/],
  });
};

看起来 webpack v5 和 v4 版本之间存在问题，但从该方面没有明显的问题需要修复。

Answer 1

我在迁移到 webpack 5 和 vue-cli-plugin-single-spa v3.3.0 时遇到了同样的问题。在您的个人应用程序中，您需要在 vue.config.js 中设置一个字段：

module.exports = {
  // various other settings such as publicPath, etc
  // ...
  configureWebpack: {
    output: {
      libraryTarget: 'system',
    },
  },
}

我不确定您是否也需要在 webpack.config.js 中设置此字段：

  return merge(defaultConfig, {
    output: {
      libraryTarget: 'system'
    },
    // other settings