Deploying MEAN Stack on CentOS 7.2

By Sumathi Kuppusamy,Alibaba Cloud Tech Share Author

Introduction

MEAN stack is one of the modern web application javascript framework that’s rapidly improving and easy to collaborate and learn. The MEAN Stack contains, from backend to frontend, a schemaless NoSQL database (MongoDB), a server-side JavaScript platform (Node.js), a web application framework running on Node.js to make it easier to write apps (Express.js), and a frontend client-side framework that runs in the browser (AngularJS).

In this article, we will walk through the steps to deploy MEAN stack on CentOS 7.2 deployed in Alibaba Cloud ECS.

Step by Step Walkthrough

Let us look at the steps in detail to deploy MEAN stack on an Alibaba Cloud ECS instance with CentOS 7.2.

Step 1: Create an instance on ECS

1. Login to Alibaba ECS console and go to “Instances” section in the left hand side bar.
2. Click on “Create Instance” in Instances page and choose the pricing model, the nearest datacenter region and zone, instance type, network type, security group, network billing type and then the operating system “CentOS 7.2 64bit”.
3. For better security, add SSH key pair and choose the created key pair from the list while creating the instance.
4. Also choose security group with strict rules.
5. After filling the instance name and other details, click on “Add to Cart”. Preview the details in the shopping cart.

1. Once VM is created, you can look at the instance details in ECS Overview page.

1. You can procure Elastic IP and assign to VM for mapping to your domain name. Otherwise by default, a temporary IP Address will be assigned.

Step 2: Install NodeJS

NodeJS is one of the faster way to build scalable network application. In order to install nodeJS, run the following commands on CentOS 7:

curl -sL https://rpm.nodesource.com/setup_4.x 
yum install -y nodejs

Sample output:

Step 3: Install MongoDB

MongoDB is the leading NoSQL database service. We will now install it on our ECS instance.

1. Setup the repo as given in the below steps by creating a file “mongodb.repo” in the directory “/etc/yum.repos.d”.

cat > /etc/yum.repos.d/mongodb.repo
[mongodb]
name=MongoDB Repository
baseurl=http://downloads-distro.mongodb.org/repo/redhat/os/x86_64/
gpgcheck=0
enabled=1

Press Ctrl+D to save and exit.

1. Install the MongoDB server by executing the following command:

yum install -y mongodb-org

1. Configuring MongoDB server in authentication mode:
   By default, when you start MongoDB server it runs in promiscuous mode. In order to restrict MongoDB server based on authentication, you need to create users and run mongod service with ‘-auth’ mode.

● Start the mongod service in noauth mode following the below command:

mongod –fork –dbpath /var/lib/mongo –logpath /var/log/meandb.log

Note: The default dbpath is /var/lib/mongo

● Create the admin user by going to mongo shell by typing “mongo” in terminal and feed in the below commands in mongo shell:

mongo
use admin
db.createUser({user:‘siteUserAdmin’,pwd:‘pa55w0rd’,roles:[{role:‘userAdminAnyDatabase’,db:‘admin’}]})

Enter the command “exit” when complete to exit from the mongo shell.

● Now stop the mongod service.

mongod –shutdown –dbpath /var/lib/mongo

● Now start the mongod service in -auth mode

mongod –fork –auth –dbpath /var/lib/mongo –logpath /var/log/meandb.log

● Create a user for your mongo collection (new-mean) by going to mongo shell in the terminal and feed in the below commands in mongo shell. You need to login to your MongoDB account by using the “-u” and “-p” commands:

 mongo -u siteUserAdmin -p pa55word --authenticationDatabase admin
use new-mean;
db.createUser({user:'meanuser',pwd:'pa55w0rd',roles:[{role:'readWrite',db:'new-mean'}]})

Enter the command “exit” when complete to exit from the mongo shell.

Note: In this example, we have used the following username and passwords. For your environment, use appropriate password of your choice.

Database	Username	Password
admin	siteUserAdmin	pa55word
new-mean	meanuser	pa55w0rd

Step 4: Installing Dependencies

a. Install the git by giving the below command:

yum install -y git

b. Install bower and gulp packages In order to bring up the MEAN stack, package managers such as npm, bower, gulp need to be installed. Bower is the package manager for web components. Install these dependencies by running the following commands: ●

sudo npm install -g bower

●

sudo npm install -g gulp

Note: ●“-g” flag is important to ensure that bower and gulp are installed globally. ●If you encounter the below error “npm: relocation error: npm: symbol SSL_set_cert_cb, version libssl.so.10 not defined in file libssl.so.10 with link time reference”, please run the following command and then re-run the above commands.

yum update -y openssl

Output:

Step 5: Installing MEAN Application

a. Clone the mean repo service and change the current working directory to mean:

git clone https://github.com/linnovate/mean.git

cd mean

(Optional) You can inspect the directory structure of mean by using the command “ls”: The package.json file describes dependencies for AngularJS, Web Components and NodeJS. MEAN uses the https://webpack.github.io/”>webpack for bundling web assets. b. Install mean project packages by running the following command:

npm install 

Note: This may take few seconds to complete. c. Configure MONGO_HOST settings in server-start.js to connect to mongo server using the created user meanuser. You can use one of the text editor ‘vi’ or ‘nano’:

nano server-start.js

Change the line containing “MONGO_HOST”: process.env.MONGO_HOST='mongodb://localhost/new-mean' To process.env.MONGO_HOST='mongodb://meanuser@pa55w0rd@localhost/new-mean' c. Start the mean service with production mode

export NODE_ENV=production
npm start

Step 6: Grant public access to your MEAN app

As a security measure, all your “inbound” network connections are blocked. You can add a rule to security group of your instance to allow inbound traffic on port 8080 through Alibaba ECS console.

Step 7: Browser access to the MEAN application

Launch the browser with the URL http://<external_ip_of_instance>:8080/ Note: Replace with the actual IP address of your ECS instance.

Summary

Thus, we could bring up a MEAN stack based web application on Alibaba Cloud ECS in just few minutes. Now, you have a fully functional https://github.com/linnovate/mean”>MEAN stack on your server!