javascript - 调试 MobileServiceClient 请求

Question

我正在开发 Azure MobileService/CordovaApp 设置。服务器在本地运行并具有以下设置来启用 CORS:

<add name="Access-Control-Allow-Origin" value="*" />

可以使用诸如

之类的地址通过浏览器调用 API

http://localhost:59477/api/item/explore/A/B

尝试描述此调用的客户端脚本如下:

var client = new WindowsAzure.MobileServiceClient('http://localhost:59477/', 'http://localhost:59477/', '');
GetItems.addEventListener("click",
function ()
{
    client.invokeApi("item/explore/A/B",
        {
            method: "get"
        })
        .done(
        function (results)
        {
            alert(results.result.count);
        },
        function (error)
        {
            var xhr = error.request;
            alert('Error - status code: ' + xhr.status + '; body: ' + xhr.responseText);
            alert(error.message);
        }
    );
}
);

我得到的是状态 405 - 方法不允许，我不明白有两个原因:

• 调用的服务操作由 [HttpGet] 属性修饰
• 响应 header 似乎表明 GET 没问题:

    HTTP/1.1 405 Method Not Allowed
    Allow: GET
    Content-Length: 76
    Content-Type: application/json; charset=utf-8
    Server: Microsoft-IIS/8.0
    X-SourceFiles: =?UTF-8?B?RjpcQ29kZVxGb290UHJpbnRzXGZvb3RwcmludHMuU2VydmVyXEZvb3RwcmludHNTZXJ2aWNlXGFwaVxmb290cHJpbnRcZXhwbG9yZVw1MS4yNzcwMjJcNy4wNDA3ODM=?=
    X-Powered-By: ASP.NET
    Access-Control-Allow-Origin: *
    Date: Sat, 15 Aug 2015 18:08:30 GMT

Any idea what I can do to get this running?

---

Edit The Raw request shows that, as already expected by Jeremy Foster, the client sends a request of the type OPTIONS:

OPTIONS http://localhost:59477/api/fp/get?id=1 HTTP/1.1
Host: localhost:59477
Connection: keep-alive
Access-Control-Request-Method: GET
Origin: http://localhost:4400
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/44.0.2403.155 Safari/537.36
Access-Control-Request-Headers: accept, x-zumo-features, x-zumo-installation-id, x-zumo-version
Accept: */*
Referer: http://localhost:4400/index.html
Accept-Encoding: gzip, deflate, sdch
Accept-Language: de-DE,de;q=0.8,en-US;q=0.6,en;q=0.4

I managed to support this request applying the [HttpOptions] attribute to my action method. Now I get a more or less valid response:

HTTP/1.1 200 OK
Content-Type: text/html; charset=utf-8
Content-Encoding: gzip
Vary: Accept-Encoding
Server: Microsoft-IIS/8.0
X-SourceFiles: =?UTF-8?B?RjpcQ29kZVxGb290UHJpbnRzXGZvb3RwcmludHMuU2VydmVyXEZvb3RwcmludHNTZXJ2aWNlXGFwaVxmcFxnZXRcMQ==?=
X-Powered-By: ASP.NET
Access-Control-Allow-Origin: *
Access-Control-Allow-Headers: Origin, X-Requested-With, Content-Type, Accept
Date: Sun, 23 Aug 2015 19:34:21 GMT
Content-Length: 234

         ...

At least that's what fiddler tells me. The AzureMobileServiceClient throws yet another issue, which roughly translates as:

Cross-Origin request blocked, missing token 'x-zumo-installation-id' in CORS header row 'Access-Control-Allow-Headers' on CORS-Preflight-Channel

Answer 1

打开Fiddler并尝试从浏览器进行 API 调用，然后再次使用移动服务客户端并比较您的原始 HTTP 请求以查看有何不同。