Deploy and run Docker in AWS

Question

I just finish my React and NodeJS project and create a Dockerfile for each one and then create a docker-compose file to create the docker image for each one (frontend and backend).

I also push my images to my repository in Docker hub. What should I do now? I want to run my docker project in AWS EC2, so I create in my AWS dashboard a new EC2 instance and install docker there and also manage to download my images from my docker hub...

But now I'm pretty stuck, do I need to create a container to run both of them? Do I need to run each one alone?

Also, I'm using Nginx to use port 80 instead of the default 3000.

I really lost now (first time working with Docker and AWS) Thanks!

EDIT 1

My dockerfile for React is:

# build environment
FROM node:13.12.0-alpine as build
WORKDIR /app
ENV PATH /app/node_modules/.bin:$PATH
COPY package.json ./
COPY package-lock.json ./
RUN npm ci --silent
RUN npm install react-scripts@3.4.1 -g --silent
COPY . ./
RUN npm run build

# production environment
FROM nginx:stable-alpine
COPY --from=build /app/build /usr/share/nginx/html
# new
COPY nginx/nginx.conf /etc/nginx/conf.d/default.conf
EXPOSE 80
CMD ["nginx", "-g", "daemon off;"]

My dockerfile for Nodejs is:

FROM node:8

# Create app directory
WORKDIR /usr/src/app

# Install app dependencies
# A wildcard is used to ensure both package.json AND package-lock.json are copied
COPY package*.json ./

RUN npm install

# Bundle app source
COPY . .

EXPOSE 5000

CMD [ "npm", "start" ]

and my Nginx config file is:

server {

  listen 80;

  location / {
    root   /usr/share/nginx/html;
    index  index.html index.htm;
    try_files $uri $uri/ /index.html;
  }

  error_page   500 502 503 504  /50x.html;

  location = /50x.html {
    root   /usr/share/nginx/html;
  }

}

my docker-compose.yml file is:

version: "2"
services:
  frontend:
    image: itaik/test-docker:frontend
    build: ./frontend
    ports:
      - "80:80"
    depends_on:
      - backend
  backend:
    image: itaik/test-docker:backend
    build: ./backend
    ports:
      - "5000:5000"

On my computer (windows) I download the Docker desktop app and I using the docker compose-up command and it's create a container with both of my images and everything is great, this is what i'm trying to achieve on my AWS EC2 (Linux). Hope things more clear now.

EDIT 2

Ok so somehow I manage to run both my images with difference containers and they are now both online like I wanted I use the command:

docker run -d -p 5000:5000 itaik/test-docker:backend

docker run -d -p 80:80 itaik/test-docker:frontend

But now, for some reason all my API calls to "localhost:5000" are getting an error:

GET http://localhost:5000/user/ net::ERR_CONNECTION_REFUSED

Is this related to my React/Nodejs code or to the way I setup my docker images?

Thanks!

EDIT 3

Even after I use docker-compose and both images are running on the same network bridge I still got that error.

The only solution I can think about is to manually edit my code and change "localhost" to AWS public IP, but I guess I just missing something that need to be done... Maybe my network bridge is not visible to the public IP somehow? Because I do get response when I enter to the public IP (port 80) and to port 5000.

But the API call to localhost:5000 is getting an error.

Answer 1

Probably the shortest path to get this working is to

• Merge frontend with backend into same docker image (because you have to serve your bundle from somewhere and backend is the nearest already prepared place for it)

• Make sure hosts and ports set up and container works properly on you machine

• Push image into DockerHub (or e.g. AWS ECR)

• Get machine At AWS EC2 and install docker there (and, if needed, Docker Compose)

• Make sure control groups for you machine allow incoming traffic to the port (right click on instance at AWS Console), your application will serve on (for your example you should open port :80)

• Pull image and start container (or 2 via docker-compose) with port set up as 80:3000 (lets assume your apps serves on :3000 on container)

• on same AWS EC2 console click on your instance and you will see public address of your machine (smth like ec2-203-0-113-25.compute-1.amazonaws.com)

• I think those are the most common pitfalls

I would recommend to deploy your app in single image (e.g. Express can easily serve your frontend-app after you built it into static bundle) because it may take some time to make containers communicate with each other.

But if you still want to serve your app with 2 components - frontend from Nginx, and backend from NodeJS, then you can use docker-compose. Just make sure that hosts for each components set up properly (they won't see each other on localhost)

---

UPD 2

There are actually 2 ways to make frontend communicate with backend (I suppose your are probably using axios or smth similar for API calls):

1st way - is to explicitly set up http://<host>:<port> as axios baseURL so all your api calls become interpolated into http://ec2-203-....amazonaws.com:3000/api/some-data. But you should know exact host, your backend is serving on. Maybe this is the most explicit and easiest way :)

2nd way - is to make browser locate your server. I'm not deeply familiar with how that works under the hood, but on high level it works like this: user gets your application as bundle from yousite.com. And app needs to fetch data from backend, but in code those calls are "relative" - only /api/some-data is stated.

As there is no backend host set up, app asks browser to locate it's "home" and, I suppose, location.hostname becomes the host for such calls, so full url becomes http://yousite.com/api/some-data.

But, as you can see, if user will make this call, it will hit Nginx instead of actual backend, because Nginx is the one who serves frontend.

So next thing that you have to do - it to proxy such calls from Nginx to NodeJs. And there is another thing - only API calls should be proxied. Other calls should, as usually, return your bundle. So you have to set up proxy this way:

location /api/ {
  proxy_pass http://backend:5000;
}

• note as NodeJs app is on backend:5000, not localhost:5000 - this how docker-compose sets up DNS

So now Nginx makes 2 things:

• Serves static content
• Reverse-proxies api calls to your backend

---

As you may have noticed, it has many tricky parts to make your app work in 2 containers. And this is how you can serve static content (from directory build) with express, so you won't need to use Nginx:

const app = express();
app.use('/', express.static(path.join(__dirname, 'build')));

---

I would recommend to try 1st way - explicitly set up host:port - and enable all the logging you can so you know whats going on. And after you are done with 1st part, update Nginx to make it work in proper way

Good luck!

Answer 2

first of all, to interact with another docker service running on the same ec2 instance, you don't need to go through the public internet.

Second, your react application cannot access the backend service via http://localhost:5000, because the backend service is not running in the same docker instance.

You should be able to access the backend service through http://backend:5000 from the react docker. Please check and get back to me.

Not related to your problem, but a suggestion,

Is your react application public-facing or internal application, if it's public-facing, you can easily run your react application from amazon S3 itself since amazon s3 supports static website hosting. you could simply copy the react application into an s3 bucket and run it as a static website. this also allows you to setup SSL via cloudfront.

hope this helps.

Reference: how to setup the s3 static website