krayzpipes / testmon2

Pipeline testing 2

testmon

Testing some CI/CD pipeline stuff

Overview

This repo was built to test out docker and CI/CD pipelines.

The Application

Features of the test application:

• Python FastAPI framework
• Two endpoints
  • /now returns a status, current server time, and the client IP as seen by the server
  • /tomorrow returns a status, current server time + 1 day, and the client IP as seen by the server.

Terraform

The terraform template creates:

• VPC / EC2
  • Private and Public subnets across two availability zones
    • Elasticache subnets
    • Fargate task subnets
    • Public subnets for NAT Gateway and Load Balancer
  • Security groups
    • ECS
      • ingress TCP 80 from load balancer subnets
      • egress HTTPS to 0.0.0.0/0 in order to pull imagees from ECR
• IAM
  • CircleCI User, Role, and Role policy for pipeline automation
  • Roles/policies for ECS Task Execution
• ECR
  • Registry for testmon
• ECS
  • Fargate cluster
  • Note: ECS Service and Task definintions will be created out of band of Terraform as Terraform does not play nicely with CI/CD deployments out of band of Terraform. Terraform also makes old tasks INACTIVE, which they cannot be rolled back to in the case of an issue.

CircleCI

• Runs linting, static analysis.
• Builds container. If on the release branch, pushes to AWS ECR.
• (coming soon) ECS-Deploy if on the release branch.

Initial deployment

1. Apply the terraform templates
2. Seed the ECS Service and Task Definition
   • ECS-Deploy (in the pipeline) does not bootstrap the ECS Service nor Task Definition. You must first seed the Service/Task Definition that ECS Deploy can then update during the CI/CD Pipeline.
   • Fill out variables and then run the scrips/seed_tasks_and_services.sh script to seed the task definition and service.
   • It's okay to reference a dummy or fake container image to get this part going.
3. Setup your CircleCI account.
   • Give access to repo
   • Setup environment context named testmon with the CircleCI user info from the terraform build.
     • AWS_ACCESS_KEY_ID
     • AWS_SECRET_ACCESS_KEY
     • AWS_DEFAULT_REGION
     • APP_NAME ('testmon' in this case)
4. Commit code and watch the wheels turn. Commit to the master branch to see the image pushed and for Fargate to begin running the application.
5. Get the load balancer DNS name to interact with the application.

Docker image for the app

$ docker build -t testmon:dev .

Run the container

$ docker run --name testmon2 -d -p 8080:8080 krayzpipes/testmon

Test it with requests

>>> import requests
>>> r = requests.get('http://127.0.0.1:8080/now')
>>> r.status_code
200
>>> r.json()
{'status': 'alive', 'time': 'Sat Feb  8 20:52:44 2020', 'ip': '172.16.0.5'}

>>> import requests
>>> r = requests.get('http://127.0.0.1:8080/tomorrow')
>>> r.status_code
200
>>> r.json()
{'status': 'alive', 'time': 'Sun Feb  9 20:53:51 2020', 'ip': '172.16.0.5'}

Terraform

Currently using terraform version 0.12.20.

Be sure to fill out your secret variables (AND DO NOT COMMIT THEM). The .gitignore file ignored *.tfvars for this purpose.

$ cp terraform.tfvars.example terraform.tfvars

Once you've added the secret variables, you can plan out the terraform work.

$ cd terraform/

$ terraform init

$ terraform plan

Terraform will plan the creation of an Elastic Container Registry, Repo, and will create a user to be used by CircleCI to push/pull images.