@appshell/manifest-webpack-plugin

Emits an appshell manifest template for building micro-frontends with Appshell and Webpack Module Federation. The appshell manifest template is subseqently processed to generate an appshell manifest.

Working examples can be found here.

Getting Started

To begin, you'll need to install @appshell/manifest-webpack-plugin:

npm install @appshell/manifest-webpack-plugin --save-dev

or

yarn add -D @appshell/manifest-webpack-plugin

or

pnpm add -D @appshell/manifest-webpack-plugin

Then add the plugin to the webpack config of each remote app module. For example:

webpack.config.js

const { AppshellManifestPlugin } = require('@appshell/manifest-webpack-plugin');

module.exports = {
  plugins: [
    new AppshellManifestPlugin({
      config: './path/to/appshell.config.yaml',
    }),
  ],
};

What is appshell.config.yaml?

A configuration file consumed by the plugin to provide additional information and context to the Appshell host about remote entrypoints, routing, display names, etc.

Sample appshell.config.yaml

remotes:
  TestModule/Foo: # Must match the scope/module defined in ModuleFederationPlugin
    url: ${APPS_TEST_URL}/remoteEntry.js # Environment variables will be expanded when the global runtime manifest is generated.
    metadata: # Use metadata to provide additional information
      route: ${FOO_ROUTE}
      displayName: Foo App
      displayGroup: main
      order: 10
      icon: ViewList

  TestModule/Bar:
    url: ${APPS_TEST_URL}/remoteEntry.js
    metadata:
      route: /bar
      displayName: Bar App
      displayGroup: main
      order: 20
      icon: ViewList

  BizModule/Biz:
    url: http://localhost:4040/remoteEntry.js
    metadata:
      route: /biz
      displayName: Biz App
      displayGroup: auxiliary
      order: 30
      icon: ViewList

environment:
  RUNTIME_ARG_1: ${RUNTIME_ARG_1}
  RUNTIME_ARG_2: ${RUNTIME_ARG_2}
  RUNTIME_ARG_3: ${RUNTIME_ARG_3}

Note the variable expansion syntax ${CRA_MFE_URL}. When the appshell manifest is generated the actual runtime environment values are injected.

Note the environment section defines runtime environment variables that are injected into the global namesapce window.__appshell_env__[module_name] when an Appshell component is loaded. See the examples for a use case.

What happens at build time?

The plugin emits a manifest template file that is subsequently used to generate the appshell manifest at runtime.

Sample output

{
  "remotes": {
    "CraModule/App": {
      "url": "${CRA_MFE_URL}",
      "metadata": {
        "route": "/cra",
        "displayName": "Example App",
        "displayGroup": "${CRA_MFE_DISPLAY_GROUP}",
        "order": 10,
        "icon": "ViewList"
      },
      "id": "3eb81a0c"
    }
  },
  "module": {
    "exposes": {
      "./App": "./src/App"
    },
    "filename": "remoteEntry.js",
    "name": "CraModule",
    "shared": {
      "react": {
        "singleton": true,
        "requiredVersion": "^18.2.0"
      },
      "react-dom": {
        "singleton": true,
        "requiredVersion": "^18.2.0"
      }
    }
  }
}

How do I generate the appshell manifest?

Use @appshell/cli in a startup script:

appshell generate manifest --template appshell.template.json

Sample appshell manifest:

{
  "remotes": {
    "CraModule/App": {
      "id": "3eb81a0c",
      "url": "http://localhost:3000/remoteEntry.js",
      "scope": "CraModule",
      "module": "./App",
      "metadata": {
        "route": "/cra",
        "displayName": "Example App",
        "displayGroup": "main",
        "order": 10,
        "icon": "ViewList"
      }
    },
    "VanillaModule/Vanilla": {
      "id": "8232ce86",
      "url": "http://localhost:5000/remoteEntry.js",
      "scope": "VanillaModule",
      "module": "./Vanilla",
      "metadata": {
        "route": "/vanilla",
        "displayName": "Example React App",
        "displayGroup": "main",
        "order": 10,
        "icon": "ViewList"
      }
    }
  },
  "modules": {
    "Appshell": {
      "name": "Appshell",
      "shared": {
        "react": {
          "singleton": true,
          "requiredVersion": "^18.2.0"
        },
        "react-dom": {
          "singleton": true,
          "requiredVersion": "^18.2.0"
        }
      }
    },
    "CraModule": {
      "exposes": {
        "./App": "./src/App"
      },
      "filename": "remoteEntry.js",
      "name": "CraModule",
      "shared": {
        "react": {
          "singleton": true,
          "requiredVersion": "^18.2.0"
        },
        "react-dom": {
          "singleton": true,
          "requiredVersion": "^18.2.0"
        }
      }
    },
    "VanillaModule": {
      "exposes": {
        "./Vanilla": "./src/App"
      },
      "filename": "remoteEntry.js",
      "name": "VanillaModule",
      "shared": {
        "react": {
          "singleton": true,
          "requiredVersion": "^18.2.0"
        },
        "react-dom": {
          "singleton": true,
          "requiredVersion": "^18.2.0"
        }
      }
    }
  },
  "environment": {
    "CraModule": {
      "RUNTIME_ARG_1": "Foo",
      "RUNTIME_ARG_2": "Biz"
    },
    "VanillaModule": {
      "RUNTIME_ARG_1": "Bar"
    }
  }
}

Options

• options

The plugin's signature:

webpack.config.js

const { AppshellManifestPlugin } = require('@appshell/manifest-webpack-plugin');

module.exports = {
  plugins: [
    new AppshellManifestPlugin({
      config: './path/to/appshell.config.yaml',
    }),
  ],
};

Options

• config

config

Type:

type config = string;

Default: appshell.config.yaml

Location of the appshell.config.yaml file.

License

MIT