dockernginxdocker-composenginx-reverse-proxyjwilder-nginx-proxy

Docker Compose and Nginx reverse proxy: I can't access the backend through the proxy

I have a project which contains 3 containers : reverse proxy container (jwilder-nginx-proxy image), fontend container (nginx container serving an application developed and bundled by Vue js) and a backend container (a node6 container serving a NodeJs+ExpressJs app). Both Backend and frontend are behind the reverse proxy. Here is how it should work in my local host:

  1. Access http://localhost:80/ and serve the gui
  2. The gui should retrieve data from the backend via http://localhost:3500

Everything seems to be working perfectly fine, Except for the backend container. When I try to access the backend, I get a '502 bad gateway' error. here is what nginx logs:

2017/12/19 06:47:28 [error] 6#6: *3 connect() failed (111: Connection 
refused) while connecting to upstream, client: 172.22.0.1, server: , 
request: "GET /favicon.ico HTTP/1.1", upstream: 
"http://172.22.0.3:3000/favicon.ico", host: "localhost:3500", referrer: 
"http://localhost:3500/"

In my backend Dockerfile i used this:

EXPOSE 3000

And here is my docker-compose.yml file:

     version: '3'
     services:
         api:
             image: myapp/api
             restart: always
             networks:
                 - myapp_network

         gui:
             image: myapp/gui

             restart: always
             networks:
                 - myapp_network
         reverse:
             image: nginx-reverse
             depends_on:
                 - api
                 - gui
             ports:
                 - 80:8080
                 - 3500:3500
             restart: always
             volumes:
                 - /var/run/docker.sock:/tmp/docker.sock
             networks:
                 - myapp_network
     networks:
         myapp_network:
             driver: bridge

Same goes for the gui, which is an nginx server listening to 8080 inside of the container and mapped to port 80 outside of it, i used this in the Dockerfile :

EXPOSE 8080

I believe that something is wrong with my nginx.conf file (the one I used to configure the reverse proxy not the GUI app) :

nginx.conf (reverse proxy config):

http
{

sendfile on;


upstream myapp-api
{
    server api:3000;
}

server
{
    listen 3500;
    add_header    Access-Control-Allow-Origin * always;
    add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
    add_header 'Access-Control-Allow-Headers' 'Content-Type';
    gzip_types text/plain text/css application/json application/x-javascript
    text/xml application/xml application/xml+rss text/javascript;
    location /
    {
        proxy_pass http://myapp-api/;
        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;
    }
}

upstream myapp-gui
{
    server gui:8080;
}

server
{
    listen 8080;
    add_header    Access-Control-Allow-Origin * always;
    add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
    add_header 'Access-Control-Allow-Headers' 'Content-Type';
    gzip_types text/plain text/css application/json application/x-javascript
    text/xml application/xml application/xml+rss text/javascript;
    location /
    {
        proxy_pass http://myapp-gui;
        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;
    }
}

}

Is there something wrong in my docker-compose file ? or the nginx config ? I used the same logic for both Frontend and Backend. Only the backend's not working. The Frontend is working.

I didnt use the expose directive in the Dockerfile of the nginx-reverse-proxy, as I'm mapping the ports in the compose file.

Hope someone can help me out.

Thank you

EDIT : It seems that everything is configured well. problem is the node js app. Seems like Nginx cant handle requests to a nodejs app... anone can help ?

Solution

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