nginx unable to forward request to a service running in a different container - docker

Question

I want to use nginx reverse proxy as an APIGateway in my microservice architecture
Problem: Nginx is unable to proxy_pass to my payment_service running in a different container. However, when I try to curl payment_service:3000 from inside nginx container, it works. So the network is ok.
docker-compose.yml
version: '3'
services:
payment_service:
container_name: payment_service
build: ./payment
ports:
- "3000:3000"
volumes:
- ./payment:/usr/app
networks:
- microservice-network
api_gateway:
image: nginx:latest
container_name: api_gateway
restart: always
volumes:
- ./default.conf:/etc/nginx/conf.d/default.conf
ports:
- 8080:8080
- 443:443
depends_on:
- payment_service
networks:
- microservice-network
networks:
microservice-network:
driver: bridge
default.conf
upstream payment_server {
server payment_service:3000 max_fails=10;
}
server {
listen 8080;
location /api/v1/payment {
proxy_pass http://payment_server;
}
}
Payment service is working fine when I directly access it using http://localhost:3000
But dont work with http://localhost:8080/api/v1/payment

Answer 1

According to the docs
If proxy_pass is specified without a URI, the request URI is passed to the server in the same form as sent by a client when the original request is processed, or the full normalized request URI is passed when processing the changed URI...
I don't know what your payment service is expecting, but I'm assuming you're trying to hit the root path. You need to add a trailing slash to the proxy_pass:
location /api/v1/payment {
proxy_pass http://payment_server/;
}
otherwise the request will be made as
http://payment_service:3000/api/v1/payment