kubernetes-microservice-app

Microservice Architecture for Python Flask Phonebook Web Application with MySQL using Kubernetes

Description

Phonebook Microservice Web Application aims to create a web application with MySQL Database using Docker and Kubernetes to have the understanding of Microservice architecture. In this application, we have a frontend service and a backend service to interact with database service. Each service will be managed by a Kubernetes deployment. The backend service will be a gateway for the application and it will serve the necessary web pages for create, delete and update operations while the frontend service will serve a search page in order to conduct read operations. To preserve the data in the database, persistent volume and persistent volume claim concepts should be adopted.

Project Architecture

Case Study Details

• Your team has started working on a project to create a Phonebook Application as Web Service.

• Software Developers in your team have already developed first version of Phonebook application. They have designed a database to keep phonebook records with following fields.

Field	Description
id	Unique identifier for records, data type is integer and it will be auto increment
name	Name of record, data type is string
number	Phone number belonging to the recorded person

• Your teammates also created the RESTful web service as given in Phonebook API using Python Flask Framework. Below table shows how the HTTP methods are designed to affect the given resources identified by URIs.

HTTP Method	Action	Example
GET	Read the records	http://[ec2-hostname]:30001/
POST	Create a new record	http://[ec2-hostname]:30001/add
POST	Update an existing record	http://[ec2-hostname]:30001/update
POST	Delete an existing record	http://[ec2-hostname]:30001/delete
POST	Delete a resource	http://[ec2-hostname]:30002

• As a DevOps engineer, you’re requested to deploy the app on an AWS EC2 Instance using Docker and Kubernetes to showcase your project. In order to achieve this goal, you need to;

  • Pull the application code from GitHub repo of your team.

  • Create two docker images for create/update/delete and search pages using Dockerfiles.

  • Deploy the app using Kubernetes. To do so;

    • Create a database service using MySQL.

    • Use a custom network for the services.

• In the Kubernetes environment, you will configure three deployements with their services and a persistent volume for MySQL deployments. You can find the definitions below for the objects you should create:

1. 1. CREATE-DELETE-UPDATE DEPLOYMENT

• Deployment definition file should configure create/delete/update operations with one or more replicas.
• Expose the container port on port 80.
• Deployment definition file should set the proper Environmental Variables for the db connection.
• Passwords should be protected by kubernetes-secrets.
• Database Host’s value should be defined in the deployment using Kubernetes-ConfigMap.

1. 1. CREATE/DELETE/UPDATE SERVICE

• This service should be attached to CREATE/DELETE/UPDATE Deployment.
• Service type should be NodePort published on port:30001.
• Expose the port and target port on port 80.

1. 1. SEARCH DEPLOYMENT

• Deployment definition file should configure search operations with one or more replicas.
• Expose the container port on port 80.
• Deployment definition file should set the proper Environmental Variables for the db connection.
• Passwords should be protected by kubernetes-secrets.
• Database Host’s value should be defined in the deployment using Kubernetes-ConfigMap.

1. 1. SEARCH SERVICE

• This service should be attached to SEARCH Deployment.
• Service type should be NodePort published on port:30002.
• Expose the port and target port on port 80.

1. 1. DATABASE DEPLOYMENT

• Deployment should use mysql:5.7 image pulled from Docker hub.
• Expose the container port on port 3306.
• Deployment definition file should set the proper Environmental Variables.
• Persistent volume should be attached to this deployment.
• Passwords should be protected by kubernetes-secrets.

1. 1. DATABASE SERVICE

• This service should be attached to DATABASE Deployment.
• Service type should be ClusterIP.
• Expose the port and target port on port 3306.

1. 1. Persistent Volume

• Volume capacity should be set as 20Gi.
• Access Mode should be set as ReadWriteOnce.
• Host path should be set as /mnt/data.
• To be able to attache this volume, a persistent volume claim should be defined.

1. 1. Kubernetes Environment

• Assign two EC2 machines as the project’s infrastructure. One should be configured as the master and the other should be configured as the worker.

• Minimum t2.medium instance type should be selected.

• The Web Application should be accessible via web browser from anywhere.

• The Application files should be downloaded from Github repo and deployed on EC2 Instance using user data script within CloudFormation Template.

DockerHub Repository

At the end of the project, following topics are to be covered;

• MySQL Database Configuration

• Docker Images

• Kubernetes architecture configuration

• AWS EC2 Service

• AWS Security Group Configuration

• Git & GitHub for Version Control System

• AWS CloudFormation Service

At the end of the project, you will be able to;

• configure a connection to the MySQL database.

• build Docker images.

• configure Kubernetes to run Python Flask app.

• improve network skills using service objects in Kubernetes

• configure AWS EC2 Instance and Security Groups.

• use git commands (push, pull, commit, add etc.) and Github as Version Control System.

• run the web application on AWS EC2 instance using the GitHub repo as codebase.

• build a Kubernetes infrastructure using CloudFormation.

Resources

• Kubernetes Documentations

• Docker Hub

• Docker

• Helm