[FIXED] How do I access a server on localhost with nginx docker container?

Issue

I'm trying to use a dockerized version of nginx as a proxy server for my node (ExpressJS) application. Without any configuration to nginx and publishing port 80 for the container, I am able to see the default nginx landing page. So I know that much is working.

Now I can mount my sites-enabled directory that contains the configuration for proxy_pass localhost:3000. I have my node application running locally (not in any Docker container) and I can access it via port 3000 (i.e. localhost:3000). However, I would assume that with nginx container running, mapped to port 80, and proxying my localhost:3000, that I would be able to see my very simple (hello world) application. Instead I receive a 502.

Do I need to pass something into docker? Is this likely a nginx configuration error? Here is my nginx configuration:

server {
  listen 0.0.0.0:80;
  server_name localhost;

  location / {
    proxy_pass http://localhost:3000;
  }
}

I have tried using this question but it did not seem to help. That is unless I'm doing something completely wrong.

Solution

You can get your current IP address as shown here:

ifconfig en0 | grep inet | grep -v inet6 | awk '{print $2}'

Then you can use the --add-host flag with docker run:

docker run --add-host localnode:$(ifconfig en0 | grep inet | grep -v inet6 | awk '{print \$2}') ...

In your proxypass use localnode instead of localhost.

Answered By - Abdullah Jibaly

Answer Checked By - David Marino (PHPFixing Volunteer)