MeteorJS中的“ Access-Control-Allow-Origin”錯誤

Question

我正在使用Laravel Lumen為我的MeteorJS應用創建API。 這是我在imports\\api\\tasks.js上的代碼和imports\\api\\tasks.js

...
import { HTTP } from 'meteor/http';
import { WebApp } from 'meteor/webapp';

if (Meteor.is_client) {

    // Calling our Meteor server's function 
    // and simply storing data into current session
    Meteor.call('fetchDataFromUrl', function (error, response) {
        Session.set('external_server_data', response)
    });


    // Providing meteor data for template (it renders on data received)
    Template.data.server_data = function () {
        return Session.get('external_server_data');
    };

}

if (Meteor.is_server) {

    Meteor.methods({
        // Declaring a method
        retrieve_doc_types: function () {
            this.unblock();
            return Meteor.http.get(api_url);
        }
    });

}

Meteor.methods({

  'tasks.insert'(make, model, year) {
    check(make, String);
    check(model, String);
    check(year, String);

    if (! Meteor.userId()) {
      throw new Meteor.Error('not-authorized');
    }

    HTTP.call("POST", "http://localhost:8000/api/v1/car",
          {data: {"make":make, "model":model, "year":year}},
        function (error, result) {

          if (!error) {
              console.log(result);
          } else{

              console.log("http post error");
          };
        });
  },

....

但是當我收到此錯誤時：

XMLHttpRequest cannot load http://localhost:8000/api/v1/car. Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:3000' is therefore not allowed access. The response had HTTP status code 405.
tasks.js:81 http post error

有人有主意嗎？ 我是MeteorJS的新手

Answer 1

在您的server / main.js中嘗試一下

WebApp.rawConnectHandlers.use(function(req, res, next) {
  res.setHeader("Access-Control-Allow-Origin", "*");
  return next();
});

Answer 2

您在哪里調用方法？ 該方法稱為tasks.insert但您提供的代碼僅調用fetchDataFromUrl方法。

這里有一些想法。

• 檢查您對客戶端的調用是否被異步使用。 從Metor HTTP文檔： On the client, this function must be used asynchronously by passing a callback. Note that some browsers first send an OPTIONS request before sending your request (in order to determine CORS headers). On the client, this function must be used asynchronously by passing a callback. Note that some browsers first send an OPTIONS request before sending your request (in order to determine CORS headers).

• 我在我的一個項目中也遇到了CORS問題，最終只使用HTTP庫服務器端。 您可以通過用Meteor.isServer環繞HTTP調用來實現。

Answer 3

有人試圖回答，但我不明白。 你試試運氣。 https://codexample.org/questions/9358/no-access-control-allow-origin-error-in-meteor-app.c

     Try package - simple:json-routes and put following code at serverside startup.
    // Enable cross origin requests for all endpoints
    JsonRoutes.setResponseHeaders({
      "Cache-Control": "no-store",
      "Pragma": "no-cache",
      "Access-Control-Allow-Origin": "*",
      "Access-Control-Allow-Methods": "GET, PUT, POST, DELETE, OPTIONS",
      "Access-Control-Allow-Headers": "Content-Type, Authorization, X-Requested-With"
    });