Pointing nginx container to static files in docker - docker

Question

I'm very new to Docker and Nginx and this might be a stupid question but how can I point my nginx box to look at the files in Rails public? Basically, I have an nginx box, and an application box. I would like to know where I can put those files so that the nginx box can read them.
version: "3"
services:
api:
build: "./api"
env_file:
- .env-dev
ports:
- "3000:3000"
depends_on:
- db
volumes:
- .:/app/api
command: rails server -b "0.0.0.0"
nginx:
build: ./nginx
env_file: .env-dev
volumes:
- .:/app/nginx
depends_on:
- api
links:
- api
ports:
- "80:80"
...
Api dockerfile:
FROM ruby:2.4.1-slim
RUN apt-get update && apt-get install -qq -y \
build-essential \
libmysqlclient-dev \
nodejs \
--fix-missing \
--no-install-recommends
ENV INSTALL_PATH /api
RUN mkdir -p $INSTALL_PATH
WORKDIR $INSTALL_PATH
COPY Gemfile $INSTALL_PATH
RUN bundle install
COPY . .
EXPOSE 3000
Nginx Dockerfile:
FROM nginx
ENV INSTALL_PATH /nginx
RUN mkdir -p $INSTALL_PATH
COPY nginx.conf /etc/nginx/nginx.conf
# COPY ?
EXPOSE 80
nginx config (this is correctly being copied over)
daemon off;
worker_processes: 1;
events { worker_connections: 1024; }
http {
sendfile on;
gzip on;
gzip_http_version 1.0;
gzip_proxied any;
gzip_min_length 500;
gzip_disable "MSIE [1-6]\.";
gzip_types text/plain text/xml text/css
text/comma-separated-values
text/javascript
application/x-javascript
application/atom+xml;
# Rails Api
upstream api {
server http://api/;
}
# Configuration for the server
server {
# Running port
listen 80;
# Proxying the connections connections
location /api {
proxy_pass http://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;
}
error_page 500 502 503 504 /public/50x.html
error_page 404 /public/404.html
location = /50x.html {
root /api/public;
}
location = /404.html {
root /api/public
}
}
}
Now, when I go to localhost:80 it show the generic nginx folder. However, I'm unsure how to link the public dir of rails api/public/ to the nginx container.
Can I just COPY path/to/rails/public path/nginx. Where is nginx expecting to find those files?
Edit
I believe I should be putting them in /var/www/app_name, correct?

Answer 1

I think what you want to achieve should be done by mounting a volume of container 'api' to container 'nginx', something like this:
version: "3"
services:
api:
image: apiimg
volumes:
- apivol:/path/to/statics
nginx:
image: nginximg
volumes:
- apivol:/var/www/statics
volumes:
apivol: {}
So there's a shared volume declared for all containers, apivol, which is mapped to /path/to/statics on your Rails container, and to /var/www/statics in your nginx container. This way you don't need to copy anything manually into the nginx container.

Answer 2

The default location for static content on nginx is /etc/nginx/html, but you could put it in var/www/app_name as long as you remember to add
root /var/www/app_name
in the corresponding location block for your static content.