Angular http返回状态0,但我认为是404 [英] Angular http returning status 0, but I expect 404
问题描述
我正在向具有以下路由的服务器发出请求:
I'm making a request to a server that has the following routes:
app.use('/401', (req, res) => res.status(401).end());
app.use('/403', (req, res) => res.status(403).end());
app.use('/404', (req, res) => res.status(404).end());
app.use('/500', (req, res) => res.status(500).end());
app.use('/502', (req, res) => res.status(502).end());
app.use('/503', (req, res) => res.status(503).end());
app.use('/504', (req, res) => res.status(504).end());
当我用Angular(/404
,{}
)发出请求时:
When I make a request with Angular (/404
, {}
):
public async post(path: string, data: object): Promise<Response> {
try {
return await this.http.post(path, data).toPromise();
} catch (err) {
console.log('err', err);
throw err;
}
}
我得到:
ok: false
status: 0
statusText: ""
type: 3
在Chrome控制台中,我看到请求是通过OPTIONS
发出的,并且确实返回了404:
In Chrome console I see the request was made with OPTIONS
and it did return 404:
Request URL: http://localhost:3000/404/
Request Method: OPTIONS
Status Code: 404 Not Found
它去哪了?如何获得真正的错误代码?
Where did it go? How can I get the real error code?
我读到它可能是CORS问题...我的应用程序在4200上,服务3000.在我的服务中,我位于顶部(之前没有其他功能):
I read that it could be a CORS issue... My app is on 4200 and my service 3000. In my service I have on the top (before anything else):
app.use(function(req, res, next) {
res.setHeader("Access-Control-Allow-Origin", "*");
res.setHeader("Access-Control-Allow-Credentials", "true");
res.setHeader("Access-Control-Allow-Methods", "*");
res.setHeader("Access-Control-Allow-Headers", "*");
next();
});
我不认为这是COR的问题...
I don't think it is a problem with CORs...
但是我不知道,是吗?
我不会得到状态为404
的err
吗?
Shouldn't I get err
with status 404
?
推荐答案
显然,OPTIONS
永远不会返回404
,因为它会导致此错误:
Apparently OPTIONS
can never return a 404
as it causes this error:
对预检的响应具有无效的HTTP状态代码404
Response for preflight has invalid HTTP status code 404
如果是OPTIONS
请求,我将标头更改为end
请求,否则继续:
I changed the headers to end
the request if it is a OPTIONS
request, otherwise it continues:
const headers = (req, res, next) => {
res.setHeader("Cache-Control", "no-cache");
res.setHeader("Access-Control-Allow-Origin", "*");
res.setHeader("Access-Control-Allow-Credentials", "true");
res.setHeader("Access-Control-Allow-Methods", "GET, HEAD, POST, PUT, PATCH, DELETE, OPTIONS");
res.setHeader("Access-Control-Allow-Headers", "Content-Type, Authorization, Accept");
};
app.use((req, res, next) => {
console.log(req.method);
headers(req, res, next);
if (req.method === 'OPTIONS') {
return res.end();
}
next();
});
然后请求在Angular应用上返回正确的数据:
Then the request return correct data on the Angular app:
ok: false
status: 404
statusText: "Not Found"
type: 2
这篇关于Angular http返回状态0,但我认为是404的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!