When using swagger as API interface document, the following error 
often occurs
If this error occurs, you can take a closer look at the console,
As can be seen from the figure, ambiguous HTTP method for action is an ambiguous HTTP operation method
Check the corresponding controller and you can see that the operation feature [httppost] or [httpget] is not added. If it is added, it will be OK.
The swagger link is accessed with the following error
Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Thu Mar 17 20:14:30 CST 2022
There was an unexpected error (type=Method Not Allowed, status=405).
Request method ‘GET’ not supported
The reason is that @PostMapping does not have a configured path
@PostMapping
public UserInfoResponse queryUserNameById(@RequestBody UserInfoRequest request){
log.info("Query user name request parameters",request);
UserInfoResponse response = userService.selectUserNameById(request);
log.info("Query user name return parameters",request);
return response;
}Scene description
A project was recently deployed. Because it is compatible with IE8, the front and back ends need to be deployed to a site. The nginx configuration is as follows:
server {
listen 80;
server_name www.aaa.ink;
client_max_body_size 1000M;
client_body_timeout 20s;
client_header_timeout 10s;
send_timeout 30s;
ssl_protocols TLSv1.2;
charset utf-8;
location ^~ /api/ {
proxy_pass http://127.0.0.1:8080/api/;
}
location ~/(.*)$ {
root /usr/local/nginx/ttm;
index index.html index.htm;
}
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root html;
}
}
Swagger is used as the interface document in the background. After the project is started, the site can be accessed normally, but an error will be reported when testing the interface in swagger. The error prompt is typeerror: failed to fetch
Problem analysis
Analysis shows that swagger’s actual request address becomes http://127.0.0.1:8080/api/ , it’s not what we actually do http://www.aaa.ink/api/ Interface address. It is found that swagger will obtain a server address according to the user’s request. Due to the use of nginx reverse proxy, swagger obtained the intranet address we configured, resulting in the request unable to respond normally.
Problem solving
location ^~ /api/ {
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Forwarded-Host $server_name;
proxy_pass http://127.0.0.1:8080/api/;
}
Set the forwarding of background items to the request header so that swagger can get the real address. The problem can be solved.