With over 14,700 stars, 2,000 forks, awesome-compose is a popular Docker repository that contains a curated list of Docker Compose samples. It helps developers learn about Docker Compose by providing a starting point for how to integrate different services using a Compose file and to manage their deployment with Docker Compose. This project is hosted over Docker GitHub organization, Inc and publicly open for the community to contribute and submit their compose file.
Most of the Docker compose samples available today are intended for use in local development environments such as project setups, tinkering with software stacks, etc. Tested dozens of these sample apps last week on Docker Desktop for Mac and it worked like a charm.
Please Note: These samples are not recommended for production environments.
How Sample Apps are Categorized?
The setups provided currently in the awesome-compose repository fit mainly in two categories:
1. Application skeletons
It is useful for kicking off project development. You will find different application skeletons with multiple services already wired together and ready to be launched with docker-compose.
2. Open-source software stacks
These setups are intended mostly for personal/home use or simply for developers to get familiar with the awesome-compose sample apps within their local dev environment.
Here’s a quick glimpse of the awesome-compose repository:
Building a Sample visitor app using Node.js, Nginx and Redis
In this tutorial , I will show how to containerize a NodeJS web application with Redis database and Nginx as a reverse proxy in front of NodeJS app using Docker.
Let’s begin building a project directory structure as shown below:
Project structure
.
├── docker-compose.yml
├── nginx
│ ├── Dockerfile
│ └── nginx.conf
├── web
│ ├── Dockerfile
│ ├── package.json
│ └── server.js
Prerequisite:
– Install Docker Desktop for Mac
Most of the awesome-compose sample apps works on Docker Desktop. Said that, it should also work on Docker distributions on Linux and Windows too. Visit https://docs.docker.com/desktop/mac/install/ to setup Docker Desktop for Mac or Windows on your local system.
ℹ️ INFO
Docker Desktop comes with Docker compose installed by default, hence you don’t need to install it separately.
Step 1. Create a Docker compose file
Create an empty file with the below content and save it by name – “docker-compose.yml”
services:
redis:
image: 'redislabs/redismod'
ports:
- '6379:6379'
web1:
restart: on-failure
build: ./web
hostname: web1
ports:
- '81:5000'
web2:
restart: on-failure
build: ./web
hostname: web2
ports:
- '82:5000'
nginx:
build: ./nginx
ports:
- '80:80'
depends_on:
- web1
- web2
The compose file defines an application with four services - redis, nginx, web1 and web2
When deploying the application, docker-compose maps port 80 of the web service container to port 80 of the host as specified in the file.
ℹ️ INFO
Redis runs on port 6379 by default. Make sure you don’t run another instance of Redis on your system or port 6379 on the host is not being used by another container, otherwise the port should be changed.
Step 2. Create an nginx directory and add the below files
File: nginx/nginx.conf
upstream loadbalancer {
server web1:5000;
server web2:5000;
}
server {
listen 80;
server_name localhost;
location / {
proxy_pass http://loadbalancer;
}
}It’s always best practice to pick up the specific Docker image version and tag it as shown below:
File: Dockerfile
FROM nginx:1.21.6
RUN rm /etc/nginx/conf.d/default.conf
COPY nginx.conf /etc/nginx/conf.d/default.conf
Step 3. Create a web directory
File: web/Dockerfile
FROM node:14.17.3-alpine3.14
WORKDIR /usr/src/app
COPY ./package.json ./
RUN npm install
COPY ./server.js ./
CMD ["npm","start"]
File: web/package.json
"name": "web",
"version": "1.0.0",
"description": "Running Node.js and Express.js on Docker",
"main": "server.js",
"scripts": {
"start": "node server.js"
},
"dependencies": {
"express": "^4.17.2",
"redis": "3.1.2"
},
"author": "",
"license": "MIT"
}
File: web/server.js
const express = require('express');
const redis = require('redis');
const app = express();
const redisClient = redis.createClient({
host: 'redis',
port: 6379
});
app.get('/', function(req, res) {
redisClient.get('numVisits', function(err, numVisits) {
numVisitsToDisplay = parseInt(numVisits) + 1;
if (isNaN(numVisitsToDisplay)) {
numVisitsToDisplay = 1;
}
res.send('Number of visits is: ' + numVisitsToDisplay);
numVisits++;
redisClient.set('numVisits', numVisits);
});
});
app.listen(5000, function() {
console.log('Web application is listening on port 5000');
});
Step 4. Creating a web1 directory and add the below files:
File: Dockerfile
FROM node:14.17.3-alpine3.14
WORKDIR /usr/src/app
COPY ./package*.json ./
RUN npm install
COPY ./server.js ./
CMD ["npm","start"]
File: server.js
const express = require('express');
const redis = require('redis');
const app = express();
const redisClient = redis.createClient({
host: 'redis',
port: 6379
});
app.get('/', function(req, res) {
redisClient.get('numVisits', function(err, numVisits) {
numVisitsToDisplay = parseInt(numVisits) + 1;
if (isNaN(numVisitsToDisplay)) {
numVisitsToDisplay = 1;
}
res.send('web1: Total number of visits is: ' + numVisitsToDisplay);
numVisits++;
redisClient.set('numVisits', numVisits);
});
});
app.listen(5000, function() {
console.log('Web app is listening on port 5000');
});
File: package.json
{
"name": "web1",
"version": "1.0.0",
"description": "Running Node.js and Express.js on Docker",
"main": "server.js",
"scripts": {
"start": "node server.js"
},
"dependencies": {
"express": "^4.17.2",
"redis": "3.1.2"
},
"author": "",
"license": "MIT"
}
Step 5. Deploy the application
Let us deploy the full-fledged app using docker-compose
$ docker-compose up -d
Creating nginx-nodejs-redis_redis_1 ... done
Creating nginx-nodejs-redis_web1_1 ... done
Creating nginx-nodejs-redis_web2_1 ... done
Creating nginx-nodejs-redis_nginx_1 ... done
Expected result
Listing containers must show three containers running and the port mapping as below:
docker-compose ps
Name Command State Ports
------------------------------------------------------------------------------------------
nginx-nodejs-redis_nginx_1 /docker-entrypoint.sh ngin Up 0.0.0.0:80->80/tcp
...
nginx-nodejs-redis_redis_1 docker-entrypoint.sh redis Up 0.0.0.0:6379->6379/tcp
...
nginx-nodejs-redis_web1_1 docker-entrypoint.sh npm Up 0.0.0.0:81->5000/tcp
start
nginx-nodejs-redis_web2_1 docker-entrypoint.sh npm Up 0.0.0.0:82->5000/tcp
start
Step 6. Testing the app
After the application starts, navigate to http://localhost:80 in your web browser or run:
curl localhost:80
curl localhost:80
web1: Total number of visits is: 1
curl localhost:80
web1: Total number of visits is: 2
$ curl localhost:80
web2: Total number of visits is: 3
$ curl localhost:80
web2: Total number of visits is: 4
Stop and remove the containers
$ docker-compose down
Step 7. Monitoring Redis keys
If you want to monitor the Redis keys, you can use monitor command. Install redis-client in your Mac system usingbrew install redis
and then directly connect to Redis container by issuing the below command:
% redis-cli
127.0.0.1:6379> monitor
OK
1646485507.290868 [0 172.24.0.2:34330] "get" "numVisits"
1646485507.309070 [0 172.24.0.2:34330] "set" "numVisits" "5"
1646485509.228084 [0 172.24.0.2:34330] "get" "numVisits"
1646485509.241762 [0 172.24.0.2:34330] "set" "numVisits" "6"
1646485509.619369 [0 172.24.0.4:52082] "get" "numVisits"
1646485509.629739 [0 172.24.0.4:52082] "set" "numVisits" "7"
1646485509.990926 [0 172.24.0.2:34330] "get" "numVisits"
1646485509.999947 [0 172.24.0.2:34330] "set" "numVisits" "8"
1646485510.270934 [0 172.24.0.4:52082] "get" "numVisits"
1646485510.286785 [0 172.24.0.4:52082] "set" "numVisits" "9"
1646485510.469613 [0 172.24.0.2:34330] "get" "numVisits"
1646485510.480849 [0 172.24.0.2:34330] "set" "numVisits" "10"
1646485510.622615 [0 172.24.0.4:52082] "get" "numVisits"
1646485510.632720 [0 172.24.0.4:52082] "set" "numVisits" "11"
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