response for preflight is invalid (redirect) error

问题

I am new to Laravel and Lumen framework. I am doing my first project using Lumen. I am trying to create an API calling from angular

Here is my angular code :

app.controller('ListCtrl', ['$scope', '$http', '$location', '$window', function($scope, $http, $location, $window) {
    $scope.data = {};

    $scope.getdata = function() {
        $scope.datas = [];

        $headers = {
            'Access-Control-Allow-Origin' : '*',
            'Access-Control-Allow-Methods' : 'POST, GET, OPTIONS, PUT',
            'Content-Type': 'application/json',
            'Accept': 'application/json'
        };

        $http({
            url: "http://localhost/service/public/getdata/", 
            method: "GET",
            params: {'place':$scope.data.place,'pincode':$scope.data.pincode},
            headers: $headers
        })
        .success(function(data,status,headers,config) {
            $scope.datas=JSON.stringify(data);

            console.log($scope.datas);

            $scope.navig('/show.html');
        })
        .error(function(){
          alert("failed");
        });
    };

    $scope.navig = function(url) {
        $window.location.href = url;
    };
}]);

And here is my Lumen route.php :

<?php

header("Access-Control-Allow-Origin: *");
header("Access-Control-Allow-Headers: Content-Type");

$app->get('/', function () use ($app) {
    return $app->version();
});

$app->get('getdata','App\Http\Controllers\PlaceController@index');

And here is PlaceController.php

<?php

namespace App\Http\Controllers;

use App\Places;
use Illuminate\Http\Request;
use App\Http\Controllers\Controller;

class PlaceController extends Controller
{

    public function __construct()
    {
        header("Access-Control-Allow-Origin: *");
        header("Access-Control-Allow-Headers: Content-Type");
        //header("Access-Control-Allow-Origin: http://localhost:8100");
    }

    public function index()
    {
        $places = Place::all();

        return response()->json($places);
    }
}

But it shows "XMLHttpRequest cannot load http://localhost/service/public/getdata/?place=sdfs. Response for preflight is invalid (redirect)" error in console.log.

I have googled for two days,but cant find a solution.

Please help

回答1:

You might be having problems due to invalid/incorrect Headers in your request. The only type of header that PlaceControllerseems to allow is Content-Type, but you're sending more than that.

Also, Access-Control-Allow-Origin and Access-Control-Allow-Methods headers should be added to the server response for your request, not to the request itself.

From MDN, cross-site requests (which seems to be your case) have to meet the following conditions:

• The only allowed methods are:
  • GET
  • HEAD
  • POST
• Apart from the headers set automatically by the user agent (e.g. Connection, User-Agent, etc.), the only headers which are allowed to be manually set are:
  • Accept
  • Accept-Language
  • Content-Language
  • Content-Type
• The only allowed values for the Content-Type header are:
  • application/x-www-form-urlencoded
  • multipart/form-data
  • text/plain

Note: I never worked with Laravel or Lumen, but in my case if I don't set the headers correctly I end up with the same response for preflight is invalid (redirect) error.

来源：https://stackoverflow.com/questions/35841786/response-for-preflight-is-invalid-redirect-error