我已经使用Node/Express创建了一个小API,并试图使用Angularjs拉数据,但由于我的html页面在localhost:8888和节点API在端口3000上监听下运行,我得到了No 'Access-Control-Allow-Origin'。我尝试使用node-http-proxy和Vhosts Apache,但没有太多成功,请参阅下面的完整错误和代码。

XMLHttpRequest无法加载localhost:3000。被请求的资源上没有'Access-Control-Allow-Origin'标头。因此,不允许访问Origin 'localhost:8888'。”

// Api Using Node/Express    
var express = require('express');
var app = express();
var contractors = [
    {   
     "id": "1", 
        "name": "Joe Blogg",
        "Weeks": 3,
        "Photo": "1.png"
    }
];

app.use(express.bodyParser());

app.get('/', function(req, res) {
  res.json(contractors);
});
app.listen(process.env.PORT || 3000);
console.log('Server is running on Port 3000')

角码

angular.module('contractorsApp', [])
.controller('ContractorsCtrl', function($scope, $http,$routeParams) {

   $http.get('localhost:3000').then(function(response) {
       var data = response.data;
       $scope.contractors = data;
   })

HTML

<body ng-app="contractorsApp">
    <div ng-controller="ContractorsCtrl"> 
        <ul>
            <li ng-repeat="person in contractors">{{person.name}}</li>
        </ul>
    </div>
</body>

当前回答

这对我很管用。

app.get('/', function (req, res) {

    res.header("Access-Control-Allow-Origin", "*");
    res.send('hello world')
})

你可以根据自己的需要改变*。希望这能有所帮助。

其他回答

app.all('*', function(req, res,next) {
    /**
     * Response settings
     * @type {Object}
     */
    var responseSettings = {
        "AccessControlAllowOrigin": req.headers.origin,
        "AccessControlAllowHeaders": "Content-Type,X-CSRF-Token, X-Requested-With, Accept, Accept-Version, Content-Length, Content-MD5,  Date, X-Api-Version, X-File-Name",
        "AccessControlAllowMethods": "POST, GET, PUT, DELETE, OPTIONS",
        "AccessControlAllowCredentials": true
    };

    /**
     * Headers
     */
    res.header("Access-Control-Allow-Credentials", responseSettings.AccessControlAllowCredentials);
    res.header("Access-Control-Allow-Origin",  responseSettings.AccessControlAllowOrigin);
    res.header("Access-Control-Allow-Headers", (req.headers['access-control-request-headers']) ? req.headers['access-control-request-headers'] : "x-requested-with");
    res.header("Access-Control-Allow-Methods", (req.headers['access-control-request-method']) ? req.headers['access-control-request-method'] : responseSettings.AccessControlAllowMethods);

    if ('OPTIONS' == req.method) {
        res.send(200);
    }
    else {
        next();
    }


});

你可以使用"$http.jsonp"

OR

下面是周围的工作铬为本地测试

你需要使用以下命令打开你的chrome浏览器。(按窗口+ R)

Chrome.exe --allow-file-access-from-files

注意:你的chrome浏览器不能打开。当你运行这个命令时,chrome浏览器会自动打开。

如果你在命令提示符中输入这个命令,然后选择你的chrome安装目录,然后使用这个命令。

下面是在MAC中使用“——allow-file-access-from-files”打开chrome的脚本代码

set chromePath to POSIX path of "/Applications/Google Chrome.app/Contents/MacOS/Google Chrome" 
set switch to " --allow-file-access-from-files"
do shell script (quoted form of chromePath) & switch & " > /dev/null 2>&1 &"

第二个选项

你可以使用open(1)来添加标志:open -a '谷歌Chrome'——args——allow-file-access-from-files

当前端和后端运行在不同的端口上时,就会发生这种情况。由于CORS标头的缺失,浏览器会阻止来自后端的响应。解决方案是在后端请求中添加CORS标头。最简单的方法是使用cors的npm包。

var express = require('express')
var cors = require('cors')
var app = express()
app.use(cors())

这将在所有请求中启用CORS报头。有关更多信息,您可以参考cors文档

https://www.npmjs.com/package/cors

/** * Allow cross origin to access our /public directory from any site. * Make sure this header option is defined before defining of static path to /public directory */ expressApp.use('/public',function(req, res, next) { res.setHeader("Access-Control-Allow-Origin", "*"); // Request headers you wish to allow res.setHeader("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept"); // Set to true if you need the website to include cookies in the requests sent res.setHeader('Access-Control-Allow-Credentials', true); // Pass to next layer of middleware next(); }); /** * Server is about set up. Now track for css/js/images request from the * browser directly. Send static resources from "./public" directory. */ expressApp.use('/public', express.static(path.join(__dirname, 'public'))); If you want to set Access-Control-Allow-Origin to a specific static directory you can set the following.

尝试在你的NodeJS/Express应用程序中添加以下中间件(为了方便起见,我添加了一些注释):

// Add headers before the routes are defined
app.use(function (req, res, next) {

    // Website you wish to allow to connect
    res.setHeader('Access-Control-Allow-Origin', 'http://localhost:8888');

    // Request methods you wish to allow
    res.setHeader('Access-Control-Allow-Methods', 'GET, POST, OPTIONS, PUT, PATCH, DELETE');

    // Request headers you wish to allow
    res.setHeader('Access-Control-Allow-Headers', 'X-Requested-With,content-type');

    // Set to true if you need the website to include cookies in the requests sent
    // to the API (e.g. in case you use sessions)
    res.setHeader('Access-Control-Allow-Credentials', true);

    // Pass to next layer of middleware
    next();
});

(您可能需要使用127.0.0.1而不是localhost。)