fix(dva): dva model import undefined when from umi

packages/plugin-dva/src/dva.tpl

@@ -4,19 +4,24 @@ import dva from 'dva';
 // @ts-ignore
 import createLoading from '{{{ dvaLoadingPkgPath }}}';
 import { plugin, history } from '../core/umiExports';
+{{ ^LazyLoad }}
 {{{ RegisterModelImports }}}
+{{ /LazyLoad }}
 {{ #dvaImmer }}
 import dvaImmer, { enableES5 } from '{{{ dvaImmerPath }}}';
 {{ /dvaImmer }}
 
 let app:any = null;
 
-export function _onCreate(options = {}) {
+export {{ #LazyLoad }}async {{ /LazyLoad }}function _onCreate(options = {}) {
   const runtimeDva = plugin.applyPlugins({
     key: 'dva',
     type: ApplyPluginsType.modify,
     initialValue: {},
   });
+  {{ #LazyLoad }}
+  {{{ RegisterModelImports }}}
+  {{ /LazyLoad }}
   app = dva({
     history,
     {{{ ExtendDvaConfig }}}
@@ -49,7 +54,13 @@ export class _DvaContainer extends Component {
     super(props);
     // run only in client, avoid override server _onCreate()
     if (typeof window !== 'undefined') {
-      _onCreate();
+      _onCreate()
+      {{ #LazyLoad }}
+        .then(() => {
+          // force update
+          this.forceUpdate();
+        });
+      {{ /LazyLoad }}
     }
   }
 
@@ -70,6 +81,11 @@ export class _DvaContainer extends Component {
 
   render() {
     const app = getApp();
+    {{ #LazyLoad }}
+    if (!app) {
+      return null;
+    }
+    {{ /LazyLoad }}
     app.router(() => this.props.children);
     return app.start()();
   }

packages/plugin-dva/src/fixtures/lazyLoad/.umirc.ts

@@ -0,0 +1,12 @@
+
+export default {
+  routes: [
+    { path: '/', component: 'index' },
+  ],
+  dva: {
+    lazyLoad: true,
+  },
+  plugins: [
+    require.resolve('../../'),
+  ],
+}

packages/plugin-dva/src/fixtures/lazyLoad/models/foo.ts

@@ -0,0 +1,9 @@
+import { data } from '../utils'
+
+export default {
+  state: {
+    desc: 'foo',
+    count: 0,
+    data,
+  },
+}

packages/plugin-dva/src/fixtures/lazyLoad/pages/index.less

@@ -0,0 +1,7 @@
+
+.normal {
+}
+
+.title {
+  background: rgb(196, 242, 121);
+}

packages/plugin-dva/src/fixtures/lazyLoad/pages/index.tsx

@@ -0,0 +1,15 @@
+import React from 'react';
+import styles from './index.less';
+import { connect } from 'dva';
+
+export const data = {};
+
+export default connect(state => ({
+  foo: state.foo,
+}))((props) => {
+  return (
+    <div>
+      <h1 className={styles.title}>Page index { props.foo.desc } { props.foo.count }</h1>
+    </div>
+  );
+})

packages/plugin-dva/src/fixtures/lazyLoad/utils.ts

@@ -0,0 +1 @@
+export { data } from './pages/index';

packages/plugin-dva/src/index.test.ts

@@ -38,3 +38,13 @@ test('with-immer', async () => {
     '<div><h1 class="title">Page index foo 1</h1><button>add</button></div>',
   );
 });
+
+test('lazyLoad', async () => {
+  const cwd = join(fixtures, 'lazyLoad');
+  await generateTmp({ cwd });
+  const { container } = render({ cwd });
+  await utils.delay(100);
+  expect(container.innerHTML).toEqual(
+    '<div><h1 class="title">Page index foo 0</h1></div>',
+  );
+});

packages/plugin-dva/src/index.ts

@@ -33,6 +33,11 @@ export default (api: IApi) => {
       schema(joi) {
         return joi.object({
           disableModelsReExport: joi.boolean(),
+          lazyLoad: joi
+            .boolean()
+            .description(
+              'lazy load dva model avoiding the import modules from umi undefined',
+            ),
           extraModels: joi.array().items(joi.string()),
           hmr: joi.boolean(),
           immer: joi.alternatives(joi.boolean(), joi.object()),
@@ -104,11 +109,15 @@ export default (api: IApi) => {
           dvaImmerES5:
             lodash.isPlainObject(api.config.dva?.immer) &&
             api.config.dva?.immer.enableES5,
+          LazyLoad: api.config.dva?.lazyLoad,
           RegisterModelImports: models
             .map((path, index) => {
-              return `import Model${lodash.upperFirst(
+              const modelName = `Model${lodash.upperFirst(
                 lodash.camelCase(basename(path, extname(path))),
-              )}${index} from '${path}';`;
+              )}${index}`;
+              return api.config.dva?.lazyLoad
+                ? `const ${modelName} = (await import('${path}')).default;`
+                : `import ${modelName} from '${path}';`;
             })
             .join('\r\n'),
           RegisterModels: models