Creating a service and deploying using docker

Following the Lab 03 we are going to create a service and attach it to our application

• It will be an update in our application

Prerequisite

The updated folder hierarchy will look like -

my-project/
├── app.py
├── dockerfile
├── requirements.txt
└── template
    └── login.html

Points to remember

• There will be change in app.py only becauyse it contains the backend and we are adding a new serviceof whihc our application is unaware of.

Update the directory

Navigate inside your working directory (my-project in my case)

mkdir template
touch template/login.html

Create/Edit a login page

Create a login page or find the entire code here (opens in a new tab)

nano template/login.html

Create/Edit backend (app.py)

Write your logic or find the entire code here (opens in a new tab)

nano app.py

Re-build and run dockerfile

To build an image using the created dockerfile

docker build -t my-app:v2 .

To avoid the naming conflict either delete the existing image or tag that image with version (used in this scenario)

The docker image of our created application is created.

To Verify

docker images --filter reference=my-app:v2

Output:

REPOSITORY    TAG       IMAGE ID       CREATED         SIZE
my-app        latest    0cf333799ced   2 seconds ago   136MB

Step 6: Create a docker container using my-app image

docker run -p 5000:5000 --name production my-app

The container is running at port 5000.

To Verify

docker ps -a

Output:

CONTAINER ID   IMAGE         COMMAND           CREATED              STATUS                          PORTS      NAMES
c5ed7ca66713   my-app        "-p 5000:80"      2 minutes ago        Created                         5000/tcp   prod

Step 7: Open your local web browser and open the following accordingly -

Run using script

wget https://xanderbilla.s3.ap-south-1.amazonaws.com/Semester_V/resources/Lab_04.sh > /dev/null 2>&1
chmod +x Lab_04.sh
./Lab_04.sh

Output:

[OK] Create project directory
[OK] Create required files
[OK] Write code in app.py
[OK] Write requirements in requirements.txt
[OK] Write code in dockerfile
[OK] Build and run Docker image

Additional Notes

• If you're using AWS EC2 make sure to update your Security group inbound rule that allow Port 5000 to 0.0.0.0/0

• Other useful docker commands that can be used are