NGINX reverse proxy not working to other docker container - docker-compose

Question

I have a setup with two docker containers in a docker compose. Now I want to use proxy_pass feature from nginx to proxy the connection from nginx to other container.
docker compose
version: '3.4'
services:
reverse_proxy:
image: nginx:alpine
volumes:
- ./nginx.conf:/etc/nginx/nginx.conf
- ./error.log:/var/log/nginx/error.log
ports:
- "8081:8081"
apigateway.api:
image: ${REGISTRY:-configurator}/apigateway.api:${TAG:-latest}
build:
context: .
dockerfile: src/Services/ApiGateway/ApiGateway.Api/Dockerfile
environment:
- ASPNETCORE_ENVIRONMENT=Development
- ASPNETCORE_URLS=http://0.0.0.0:80
ports:
- "58732:80"
nginx conf
worker_processes 1;
events {
multi_accept on;
worker_connections 65535;
}
http {
charset utf-8;
sendfile on;
tcp_nopush on;
tcp_nodelay on;
server_tokens off;
log_not_found off;
types_hash_max_size 2048;
client_max_body_size 16M;
# MIME
include mime.types;
default_type application/octet-stream;
upstream apigateway {
server apigateway.api:58732;
}
server {
listen 8081;
# reverse proxy
location /configurator-api-gw/ {
proxy_pass http://apigateway/;
proxy_redirect off;
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-Host $server_name;
}
}
}
When I now access http://localhost:8081/configurator-api-gw/swagger I'm getting following error in the error.log. I have tried also different approaches and some other examples but I don't get it why this is not working.
2019/03/08 06:30:29 [error] 7#7: *6 connect() failed (111: Connection
refused) while connecting to upstream, client: 172.28.0.1, server: ,
request: "GET /configurator-api-gw/swagger HTTP/1.1", upstream:
"http://172.28.0.5:58732/swagger", host: "localhost:8081"

Answer 1

I have solved the problem. The problem is with server apigateway.api:58732; Here it needs to be used Port 80 as this inside of the docker network.