How does nginx do port forwarding

problem description

frontend local mook data, The front-end project in http://127.0.0.1:3000/
Mook data node service in http://127.0.0.1:4003/
all cross-domain request interfaces similar to this
http. : / / 127.0.0.1 : 3000/api/activity/list
begins with / api/. How to use nginx to achieve port forwarding and solve the local cross-domain problem?

the environmental background of the problems and what methods you have tried

related codes

/ / Please paste the code text below (do not replace the code with pictures)
this is useless, how can configuration solve the problem?

    server {
        listen 3000;
        -sharpserver_name 127.0.0.1;
        
        location / {
            
            proxy_pass http://127.0.0.1:4003/;

            -sharprewrite /api/(.*)  localhost:4003/api/$1 break;
            -sharphttp://127.0.0.1:4003
            -sharpproxy_pass http://127.0.0.1:4003;
            -sharpadd_header "Access-Control-Allow-Origin" "*";
            -sharproot /Users/member/work/mhy/ax-h5/server/;
            -sharpindex index.html index.htm;
            -sharpproxy_set_header Host $host;
            -sharpproxy_set_header X-Real-IP $remote_addr;
            -sharpproxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        }
    }

what result do you expect? What is the error message actually seen?

the expected result is that all interfaces starting with / api/ are forwarded to port 4003 for data

Oct.30,2021

location /api/

location /api {
    proxy_pass http://127.0.0.1:4003
}
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b3939b-2c172.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b3939b-2c172.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?