(Angular 6)Angular Universal - 不等待内容API调用

Question

将Angular Universal与使用动态内容的页面一起使用时,无法使SSR正常工作.所有其他页面都有效,动态页面返回HTML但不包含动态数据.

方法叫:

ngOnInit() {
  const div = this.renderer.createElement('div');
  const texttest = this.renderer.createText('this works');

  this.renderer.appendChild(div, texttest);
  this.renderer.appendChild(this.content.nativeElement, div);

  this.createLinkForCanonicalURL();

  // The HTML never shows, the method works fine.
  this._contentfulService.getBlogPosts().then(posts => {
    this.blogPosts = _.orderBy(posts, ['sys.createdAt'], ['desc']);
  });
}

服务方式

getBlogPosts(query ? : object): Promise<Entry<any>[]> {
  return this.cdaClient.getEntries(Object.assign({
      content_type: CONFIG.contentTypeIds.blogPosts
    }, {
      'fields.private': false
    }))
    .then(res => res.items);
}

模板:

这从未在源中显示.

<li class="blog-post" *ngFor="let post of blogPosts">
  <h1>{{post.fields.title}}</h1>
</li>

尝试过入门套件并且它们无法调用相同的方法.还尝试使用render2注入和解析器服务来测试在加载之前获取数据.

似乎什么都没有用？

任何帮助,将不胜感激!

编辑

这是我的server.ts文件

// These are important and needed before anything else
import 'zone.js/dist/zone-node';
import 'reflect-metadata';

import { enableProdMode } from '@angular/core';
import * as express from 'express';
import { join } from 'path';

// Faster server renders w/ Prod mode (dev mode never needed)
enableProdMode();

// Express server
const app = express();

const PORT = process.env.PORT || 8080;
const DIST_FOLDER = join(process.cwd(), 'dist');

// * NOTE :: leave this as require() since this file is built Dynamically from webpack
const { AppServerModuleNgFactory, LAZY_MODULE_MAP } = 
require('./dist/server/main');

// Express Engine
import { ngExpressEngine } from '@nguniversal/express-engine';
// Import module map for lazy loading
import { provideModuleMap } from '@nguniversal/module-map-ngfactory-loader';

app.engine('html', ngExpressEngine({
  bootstrap: AppServerModuleNgFactory,
  providers: [
    provideModuleMap(LAZY_MODULE_MAP)
 ]
}));

app.set('view engine', 'html');
app.set('views', join(DIST_FOLDER, 'browser'));

// TODO: implement data requests securely
app.get('/api/*', (req, res) => {
  res.status(404).send('data requests are not supported');
});

// Server static files from /browser
app.get('*.*', express.static(join(DIST_FOLDER, 'browser')));

// All regular routes use the Universal engine
app.get('*', (req, res) => {
  res.render('index', { req });
});

// Start up the Node server
app.listen(PORT, () => {
  console.log(`Node server listening on http://localhost:${PORT}`);
});

和我的应用服务器模块

@NgModule({
bootstrap: [AppComponent],

imports: [
    BrowserModule.withServerTransition({ appId: 'app-root' }),

    AppModule,
    ModuleMapLoaderModule,
    ServerModule,
    NoopAnimationsModule,
    ServerTransferStateModule, // comment
]
})
export class AppServerModule { }

Answer 1

您需要使用TransferHttpCacheModule来等待对 API 的 HTTP 调用，或者使用另一个与 TransferState 配合使用的实现，例如ngx-transfer-http。

我的示例等待 3 秒延迟：https://github.com/Angular-RU/angular-universal-starter/blob/master/src/app/transfer-back/transfer-back.component.ts