Question

我在从我网站的链接加载字体时遇到问题。在我所看到的内容中，我的server.js中出现错误，我的标头中没有CORS。现在，我的问题是如何将标题插入我的server.js有人可以帮助我吗？

这是错误

来自“我的网站链接”的字体已被阻止通过跨源资源共享策略加载：请求的资源上没有“Access-Control-Allow-Origin”标头。因此，不允许来源“http://localhost:3001”访问

const app = express();

//
// Tell any CSS tooling (such as Material UI) to use all vendor prefixes if the
// user agent is not known.
// -----------------------------------------------------------------------------
global.navigator = global.navigator || {};
global.navigator.userAgent = global.navigator.userAgent || 'all';

//
// Register Node.js middleware
// -----------------------------------------------------------------------------
app.use(express.static(path.join(__dirname, 'public')));
app.use(cookieParser());
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());

//
// Authentication
// -----------------------------------------------------------------------------
app.use(expressJwt({
  secret: auth.jwt.secret,
  credentialsRequired: false,
  getToken: req => req.cookies.id_token,
}));
app.use(passport.initialize());

app.get('/login/facebook',
  passport.authenticate('facebook', { scope: ['email', 'user_location'], session: false })
);
app.get('/login/facebook/return',
  passport.authenticate('facebook', { failureRedirect: '/login', session: false }),
  (req, res) => {
    const expiresIn = 60 * 60 * 24 * 180; // 180 days
    const token = jwt.sign(req.user, auth.jwt.secret, { expiresIn });
    res.cookie('id_token', token, { maxAge: 1000 * expiresIn, httpOnly: true });
    res.redirect('/');
  }
);

//
// Register API middleware
// -----------------------------------------------------------------------------
app.use('/graphql', expressGraphQL(req => ({
  schema,
  graphiql: true,
  rootValue: { request: req },
  pretty: process.env.NODE_ENV !== 'production',
})));

//
// Register server-side rendering middleware
// -----------------------------------------------------------------------------
app.get('*', async (req, res, next) => {
  try {
    let css = [];
    let statusCode = 200;
    const data = { title: '', description: '', style: '', script: assets.main.js, children: '' };

    await UniversalRouter.resolve(routes, {
      path: req.path,
      query: req.query,
      context: {
        insertCss: (...styles) => {
          styles.forEach(style => css.push(style._getCss())); // eslint-disable-line no-underscore-dangle, max-len
        },
        setTitle: value => (data.title = value),
        setMeta: (key, value) => (data[key] = value),
      },
      render(component, status = 200) {
        css = [];
        statusCode = status;
        data.children = ReactDOM.renderToString(component);
        data.style = css.join('');
        return true;
      },
    });

    const html = ReactDOM.renderToStaticMarkup(<Html {...data} />);

    res.status(statusCode);
    res.send(`<!doctype html>${html}`);
  } catch (err) {
    next(err);
  }
});

//
// Error handling
// -----------------------------------------------------------------------------
const pe = new PrettyError();
pe.skipNodeFiles();
pe.skipPackage('express');

app.use((err, req, res, next) => { // eslint-disable-line no-unused-vars
  console.log(pe.render(err)); // eslint-disable-line no-console
  const statusCode = err.status || 500;
  const html = ReactDOM.renderToStaticMarkup(
    <Html
      title="Internal Server Error"
      description={err.message}
      style={errorPageStyle._getCss()}
      userAgent={req.headers['user-agent']}> // eslint-disable-line no-underscore-dangle
      {ReactDOM.renderToString(<ErrorPage error={err} />)}
    </Html>
  );
  res.status(statusCode);
  res.send(`<!doctype html>${html}`);
});

//
// Launch the server
// -----------------------------------------------------------------------------
/* eslint-disable no-console */
models.sync().catch(err => console.error(err.stack)).then(() => {
  app.listen(port, () => {
    console.log(`The server is running at http://localhost:${port}/`);
  });
});
/* eslint-enable no-console */

Answer 1

直接从this网站，在快递中启用CORS：

app.use(function(req, res, next) {
  res.header("Access-Control-Allow-Origin", "*");
  res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
  next();
});

app.get('/', function(req, res, next) {
  // Handle the get for this route
});

app.post('/', function(req, res, next) {
 // Handle the post for this route
});

Answer 2

您可以插入标题，如下所示。这对我的项目没有任何问题。

// Where app -> const app = express(); 
app.use(function(req, res, next) {
    res.header("Access-Control-Allow-Origin", "*");
    res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
    next();
});

顺便说一句，您可以改进代码，将路由逻辑与app.js分开，并使用路由器：http://expressjs.com/es/api.html#router

希望它有所帮助。

Answer 3

从npm安装 cors ，

npm install cors

然后，将其添加为中间件

app.use(cors());

好运！

ReactJS No'Access-Control-Allow-Origin'

3 个答案: