Skip to main content

Deploy Your Flask App to Kubernetes Using EKS

Source code: vnk8071/server_deployment_containerization

Template Pipeline: vnk8071/pipeline-deploy-kubernetes-on-aws

Prerequisites​

#  Mac/Linux/Windows
python --version

You can download a specific release version from here.

  • Python package manager - PIP 19.x or higher. PIP is already installed in Python 3 >=3.4 downloaded from python.org . However, you can upgrade to a specific version, say 20.2.3, using the command:
#  Mac/Linux/Windows Check the current version
pip --version
# Mac/Linux
pip install --upgrade pip==20.2.3
# Windows
python -m pip install --upgrade pip==20.2.3
  • Terminal
    • Mac/Linux users can use the default terminal.
    • Windows users can use either the GitBash terminal or WSL.
  • Command line utilities:
    • AWS CLI installed and configured using the aws configure command. Another important configuration is the region. Do not use the us-east-1 because the cluster creation may fails mostly in us-east-1. Let's change the default region to:
    aws configure set region us-east-2
    Ensure to create all your resources in a single region.
    • EKSCTL installed in your system. Follow the instructions available here or here to download and install eksctl utility.
    • The KUBECTL installed in your system. Installation instructions for kubectl can be found here.

Installation​

Install AWS CLI​

curl "https://awscli.amazonaws.com/AWSCLIV2.pkg" -o "AWSCLIV2.pkg"
sudo installer -pkg AWSCLIV2.pkg -target /

Reference: https://docs.aws.amazon.com/cli/latest/userguide/getting-started-install.html

AWS Configure​

aws configure
export AWS_CONFIG_FILE=~/.aws/config
export AWS_SHARED_CREDENTIALS_FILE=~/.aws/credentials

Install Eksctl​

brew tap weaveworks/tap
brew install weaveworks/tap/eksctl

Install Kubectl​

brew install kubectl

Monitoring Kubernetes Cluster​

brew install k9s

Install packages​

pip install -r requirements.txt

Build Application​

Run locally​

python main.py

Request method POST:

export TOKEN=`curl --data '{"email":"khoivn@email.com","password":"mypwd"}' --header "Content-Type: application/json" -X POST localhost:8080/auth  | jq -r '.token'`

Response: echo $TOKEN

eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJleHAiOjE2OTc5NjUyNjcsIm5iZiI6MTY5Njc1NTY2NywiZW1haWwiOiJraG9pdm5AZW1haWwuY29tIn0.hZr2RQqnroNdly_j9yRKpO7Z6yEwx7pNleFfB25IjHs

Request method GET:

curl --request GET 'http://localhost:8080/contents' -H "Authorization: Bearer ${TOKEN}" | jq .

Response:

{
  "email": "khoivn@email.com",
  "exp": 1697965267,
  "nbf": 1696755667
}

Run Pytest​

pytest test_main.py --disable-pytest-warnings

Result:

=================================================================================== test session starts ====================================================================================
platform darwin -- Python 3.8.18, pytest-6.2.2, py-1.11.0, pluggy-0.13.1
rootdir: /Users/macos/projects/Kelvin/pipeline-deploy-kubernetes-on-aws
collected 2 items

test_main.py ..                                                                                                                                                                      [100%]

============================================================================== 2 passed, 5 warnings in 0.22s ===============================================================================

Build Docker Image​

docker build -t token-flask-app .

Run Docker Container​

docker run --detach --publish 80:8080 --env-file=.env_file token-flask-app

Test Docker Container​

export TOKEN=`curl --data '{"email":"khoivn@email.com","password":"mypwd"}' --header "Content-Type: application/json" -X POST localhost:80/auth  | jq -r '.token'`

Result:

curl --request GET 'http://localhost:80/contents' -H "Authorization: Bearer ${TOKEN}" | jq .

Result"

{
  "email": "khoivn@email.com",
  "exp": 1697977237,
  "nbf": 1696767637
}

Push Docker Image to Docker Hub​

docker tag token-flask-app:latest vnk8071/token-flask-app:latest
docker push vnk8071/token-flask-app:latest

Deploy Application to Kubernetes Cluster​

Create EKS Cluster​

eksctl create cluster --name eksctl-demo-flask-token --nodes=2 --instance-types=t2.medium --region=us-east-1

eksctl_create

Get cluster information:

kubectl get nodes

get_nodes

k9s_deployment

Get current AWS account​

aws sts get-caller-identity --query Account --output text

Result: 993324276116

Create IAM Role and attach policy​

aws iam create-role --role-name UdacityFlaskDeployCBKubectlRole --assume-role-policy-document file://trust.json --output text --query 'Role.Arn'

Result: arn:aws:iam::993324276116:role/UdacityFlaskDeployCBKubectlRole

aws iam put-role-policy --role-name UdacityFlaskDeployCBKubectlRole --policy-name eks-describe --policy-document file://iam-role-policy.json

Set Environment Variables​

aws ssm put-parameter --name JWT_SECRET --value "KhoiVN-secret" --type  SecureString --region us-east-1

Create Kubernetes ConfigMap​

kubectl get -n kube-system configmap/aws-auth -o yaml > /tmp/aws-auth-patch.yml
kubectl patch configmap/aws-auth -n kube-system --patch "$(cat /tmp/aws-auth-patch.yml)"

Result: configmap/aws-auth patched

Get GitHub Access Token​

In GitHub, go to Settings > Developer settings > Personal access tokens > Generate new token

Create CloudFormation Stack​

  1. Modify ci-cd-codepipeline.cfn.yaml file
  2. Review the resources
  3. Create stack

cloudformation_stack

Create CodePipeline​

Details in buildspec.yml file

Check CodePipeline Deployment​

codepipeline_build

Test Endpoint​

kubectl get services simple-jwt-api -o wide

kubectl_service

Request method POST:

export TOKEN=`curl -d '{"email":"khoivn@email.com","password":"mypwd"}' -H "Content-Type: application/json" -X POST ad4d5c8ff64e142a7b7adba1b35a5b56-2013205018.us-east-1.elb.amazonaws.com/auth  | jq -r '.token'`

Request method GET:

curl --request GET 'ad4d5c8ff64e142a7b7adba1b35a5b56-2013205018.us-east-1.elb.amazonaws.com/contents' -H "Authorization: Bearer ${TOKEN}" | jq

Result:

{
  "email": "khoivn@email.com",
  "exp": 1698029355,
  "nbf": 1696819755
}

Delete CloudFormation Stack​

aws cloudformation delete-stack --stack-name <stack-name>

Delete EKS Cluster​

eksctl delete cluster --name <eksname> --region=us-east-1

Monitoring​

Deployments​

k9s_deploymments

Pods​

k9s_pods

Containers​

k9s_containers

Logs​

k9s_logs

Auto CI/CD​

Push new commit to GitHub​

push_new_commit

Check CodePipeline Deployment​

trigger_new_commit