使用 .net HttpClient 请求 github-api 说 Forbidden

Question

我正在尝试从此 github api link https://api.github.com/users/arif2009 获取数据。使用 posman get 请求可以正常工作。

但是如果我尝试使用 .net HttpClient 获取数据，那么它会显示 Forbidden.

C#代码：

using (var client = new HttpClient())
{
    client.BaseAddress = new Uri("https://api.github.com/");
    client.DefaultRequestHeaders.Accept.Clear();
    client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

    var response = await client.GetAsync("users/arif2009");

    if (response.IsSuccessStatusCode)
    {
        var data = response.Content.ReadAsAsync<GithubUser>();
    }
}

回复：

谁能告诉我我哪里出错了？

Answer 1

我使用 Telerik 的 Fiddler 查看了您的请求并发现了以下内容。

使用您的代码请求：

GET https://api.github.com/users/arif2009 HTTP/1.1
Accept: application/json
Host: api.github.com

来自邮递员的请求：

GET https://api.github.com/users/arif2009 HTTP/1.1
Host: api.github.com
Connection: keep-alive
Accept: application/json
Cache-Control: no-cache
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/75.0.3770.142 Safari/537.36
Postman-Token: d560ee28-b1e8-ece5-2612-87371ddcb295
Accept-Encoding: gzip, deflate, br
Accept-Language: en-GB,en;q=0.9,ja-JP;q=0.8,ja;q=0.7,en-US;q=0.6

明显缺失的header好像是"User-Agent"，所以我加了这个：

client.DefaultRequestHeaders.UserAgent.Add(new ProductInfoHeaderValue("product", "1")); // set your own values here

产生了以下请求：

GET https://api.github.com/users/arif2009 HTTP/1.1
Accept: application/json
User-Agent: product/1
Host: api.github.com

并返回以下响应：

HTTP/1.1 200 OK
Date: Wed, 17 Jul 2019 15:19:35 GMT
Content-Type: application/json; charset=utf-8
Content-Length: 1249
Server: GitHub.com
Status: 200 OK
X-RateLimit-Limit: 60
X-RateLimit-Remaining: 52
X-RateLimit-Reset: 1563380375
Cache-Control: public, max-age=60, s-maxage=60
Vary: Accept
ETag: "1df3e0be6e824ca684f27963806533da"
Last-Modified: Tue, 16 Jul 2019 05:58:59 GMT
X-GitHub-Media-Type: github.v3
Access-Control-Expose-Headers: ETag, Link, Location, Retry-After, X-GitHub-OTP, X-RateLimit-Limit, X-RateLimit-Remaining, X-RateLimit-Reset, X-OAuth-Scopes, X-Accepted-OAuth-Scopes, X-Poll-Interval, X-GitHub-Media-Type
Access-Control-Allow-Origin: *
Strict-Transport-Security: max-age=31536000; includeSubdomains; preload
X-Frame-Options: deny
X-Content-Type-Options: nosniff
X-XSS-Protection: 1; mode=block
Referrer-Policy: origin-when-cross-origin, strict-origin-when-cross-origin
Content-Security-Policy: default-src 'none'
Vary: Accept-Encoding
X-GitHub-Request-Id: D5E0:8D63:8BE92C:A799AE:5D2F3C86

{"login":"arif2009","id":6396346,"node_id":"MDQ6VXNlcjYzOTYzNDY=","avatar_url":"https://avatars0.githubusercontent.com/u/6396346?v=4","gravatar_id":"","url":"https://api.github.com/users/arif2009","html_url":"https://github.com/arif2009","followers_url":"https://api.github.com/users/arif2009/followers","following_url":"https://api.github.com/users/arif2009/following{/other_user}","gists_url":"https://api.github.com/users/arif2009/gists{/gist_id}","starred_url":"https://api.github.com/users/arif2009/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/arif2009/subscriptions","organizations_url":"https://api.github.com/users/arif2009/orgs","repos_url":"https://api.github.com/users/arif2009/repos","events_url":"https://api.github.com/users/arif2009/events{/privacy}","received_events_url":"https://api.github.com/users/arif2009/received_events","type":"User","site_admin":false,"name":"Arif","company":"@BrainStation-23 ","blog":"https://arif2009.github.io/","location":"Bangladesh","email":null,"hireable":true,"bio":"Software Engineer | Full Stack | Web Developer | Technical Writer","public_repos":15,"public_gists":2,"followers":9,"following":7,"created_at":"2014-01-14T05:03:47Z","updated_at":"2019-07-16T05:58:59Z"}

Answer 2

您可以尝试将完整的 URI 放入 GetAsync 而不是使用 BaseAddress，因为您没有给 GetAsync 一个 URI，而只是一个字符串。

When sending a HttpRequestMessage with a relative Uri, the message Uri will be added to the BaseAddress property to create an absolute Uri.

https://docs.microsoft.com/de-de/dotnet/api/system.net.http.httpclient.baseaddress?view=netframework-4.8

Answer 3

来自 github 的 API reference 说 'User-Agent' 是必需的 header:

All API requests MUST include a valid User-Agent header. Requests with no User-Agent header will be rejected.

当用户未提供时，Postman 会自动将其自己的 User-Agent 添加到调用中。（@John 的回答很好地证明了这一点）。

只需添加此 header 即可解决您的问题：

client.DefaultRequestHeaders.UserAgent.Add(new ProductInfoHeaderValue("yourAppName", "yourVersionNumber"));

使用 .net HttpClient 请求 github-api 说 Forbidden

Requesting to github-api using .net HttpClient says Forbidden

c#

github-api

asp.net-web-api