How to configure nginx for reverse proxy - nginx

Question

I want to reverse proxy 172.17.0.6:8080/swagger-u.html or 172.17.0.8:8080/swagger-u.html by 172.17.0.4:8080/swagger-u.html, i need configuration for Nginx, some help please!
this is my nginx.conf:
[root#5e1ae14b79e8 /]# vi /etc/nginx/nginx.conf
# For more information on configuration, see:
# * Official English Documentation: http://nginx.org/en/docs/
# * Official Russian Documentation: http://nginx.org/ru/docs/
user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;
# Load dynamic modules. See /usr/share/nginx/README.dynamic.
include /usr/share/nginx/modules/*.conf;
events {
worker_connections 1024;
}
http {
upstream backends {
server 172.17.0.7:8012 weight=3;
server 172.17.0.6:8012;
}
log_format main '$remote_addr - $remote_user [$time_local] "$request" '
'$status $body_bytes_sent "$http_referer" '
'"$http_user_agent" "$http_x_forwarded_for"';
access_log /var/log/nginx/access.log main;
sendfile on;
tcp_nopush on;
tcp_nodelay on;
keepalive_timeout 65;
types_hash_max_size 2048;
include /etc/nginx/mime.types;
default_type application/octet-stream;
# Load modular configuration files from the /etc/nginx/conf.d directory.
# See http://nginx.org/en/docs/ngx_core_module.html#include
# for more information.
include /etc/nginx/conf.d/*.conf;
server {
listen 80 default_server;
listen [::]:80 default_server;
server_name 172.17.0.4;
# Load configuration files for the default server block.
include /etc/nginx/default.d/*.conf;
location /wagger-u.html/ {
proxy_pass http://backends;
proxy_redirect off;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
}
error_page 404 /404.html;
location = /40x.html {
But,I visit 172.17.0.4:8080/swagger-u.html,it is 404!