How to deploy a WebApp on EC2 Instance with Flask

Today we are going to deploy a web application on the AWS cloud that perform a regression and plot the results on the web browser. This method can be used to deploy different Machine Learning models.

Introduction

Amazon Elastic Compute Cloud (Amazon EC2) is a web service that provides secure, resizable compute capacity in the cloud. It is designed to make web-scale cloud computing easier for developers. Amazon EC2’s simple web service interface allows you to obtain and configure capacity with minimal friction. It provides you with complete control of your computing resources and lets you run on Amazon’s proven computing environment.

Amazon EC2 offers the broadest and deepest compute platform with choice of processor, storage, networking, operating system, and purchase model.

Flask is a lightweight WSGI web application framework. It is designed to make getting started quick and easy, with the ability to scale up to complex applications. It began as a simple wrapper around Werkzeug and Jinja and has become one of the most popular Python web application frameworks.

EC2 Instance Setup

First we need to enter to the AWS Management Console

https://aws.amazon.com/it/console/

We enter with our credentials and we enter to the EC2 service

We launch an instance

We Select Amazon Linux 2 AMI (HVM), SSD Volume Type with the default settings

We add the tag, Name with the value WebApplication

For the Security Group, for this example, we assign open the port 22 TCP and the Custom 5000 for the Flask application.

For the key pair , we can create new key pair or use your key pair.

If you don’t have your keypair you have create and download.

Because you will use in order to enter to the server.

Finally we launch our EC2 Instance.

We return back to the EC2 Dashboard and we copy the IPv4 Public IP

1. We go to our terminal and with our IPv4 Public IP that should be different to mine

   you type

ssh [email protected] -i MyKey.pem

we apply all updates

sudo yum update -y

there are two ways to run the Flask Application,

a) Docker with Flask

b) Flask without Docker

Both options are good but if you use docker you have the advantage to install in different platforms.

I prefer use Docker but I going to install Python and Flask on the EC2 Instances to have both options.

Docker Installation on EC2

sudo amazon-linux-extras install docker

we start the docker daemon

 sudo service docker start

We want add the privilege to the ec2-user to use docker

sudo usermod -a -G docker ec2-user

Python Installation on EC2

In addition to Docker, and have the opportunity to execute in natural way the python programs we install python on the EC2 Instance

sudo yum install python37

we check if was installed

python --version

sudo yum install python37

python3 --version

We want to install pip, on EC2 instance, so we execute this script

 curl -O https://bootstrap.pypa.io/get-pip.py

python3 get-pip.py --user

pip --version

If everything was done correctly

we got

[ec2-user@ip-172-31-63-203 ~]$ pip --version
pip 20.2.4 from /home/ec2-user/.local/lib/python3.7/site-packages/pip (python 3.7)

we can remove the downloaded file

rm get-pip.py

Finally we can exit and start with everything running properly.

exit

Web Application Installation

We enter again to our EC2 server

ssh [email protected] -i MyKey.pem

We check if now we can run docker

docker info

Now we can do a test, by running the hello-world

 docker run hello-world

It is possible list the active Docker containers

docker ps -a

Let us remove the hello-world container, lets copy the CONTANIER ID and delete

docker rm 0d69fdc5d8e1

there is not any running container

docker ps -a

Docker Container Installation

First we create the folder where we want to install the webapp

mkdir DockerContainer

and we enter there

cd DockerContainer/

We choose a dataset that we want to perform the regression,

curl -o ./tempYearly.csv -k https://raw.githubusercontent.com/ruslanmv/DockerContainer/master/tempYearly.csv

we download the docker file

curl -o ./Dockerfile -k https://raw.githubusercontent.com/ruslanmv/DockerContainer/master/Dockerfile

and the dependencies of our webapp

curl -o ./requirements.txt -k https://raw.githubusercontent.com/ruslanmv/DockerContainer/master/requirements.txt

and we create the folder where we will put the python codes

mkdir app

cd app

Those file are already used in previous posts. https://ruslanmv.com/blog/creation-of-container

curl -o ./app.py -k https://raw.githubusercontent.com/ruslanmv/DockerContainer/master/app/app.py

curl -o ./plotdata.py -k https://raw.githubusercontent.com/ruslanmv/DockerContainer/master/app/plotdata.py

cd ..

Building the Docker WebApp

docker build --tag flask-plotting-app . 

this create the container flask-plotting-app:latest

Successfully tagged flask-plotting-app:latest

Execution of the WebApp

We can execute the container by the following command

docker run -i -t --name flaskpltapp -p5000:5000 flask-plotting-app:latest

if everthing was done well you will get the following message

Run the WebApp on the Browser

We copy our public IP of the EC2 Instance

and you write you IP following by the port 5000 , for example : http://100.25.16.80:5000/ on your web browser and finally you got the regression plot

also you can use the public DNS http://ec2-100-25-16-80.compute-1.amazonaws.com:5000/

each time you execute you python program, you can visualize on the terminal, the logs of that.

you can close the application by using CTRL+C to quit.

Web Application without Docker

The second method simpler, consists in the installation of all dependencies of your webapp by using pip3.

go to your terminal there

pip3 install -r requirements.txt

and to run your application just execute them as

python3 ./app/app.py

and wualaaa

again you go the plot , but now without the docker. Finally, in order to avoid costs on AWS, don’t forget terminate our instance.

Congratulations! we could perform a Regression Plot with our web app on AWS.