OCI Frontend and Backend for DevOps

Deploy with Terraform and Ansible your frontend (React.js) and backend (Python Flask) on OCI.

Requirements

• Oracle Cloud Infrastructure account
• OCI CLI, Terraform and Ansible configured.

TODO

• LB Health Checks in warning

Set Up

Clone this repository in your local machine:

git clone https://github.com/vmleon/oci-fe-be-devops.git

Change directory to the oci-fe-be-devops:

cd oci-fe-be-devops

Export an environment variable with the base directory:

export BASE_DIR=$(pwd)

Build

Build the frontend static content.

Change directory to the frontend code:

cd $BASE_DIR/src/frontend

NOTE: For the next step, make sure you have an up-to-date version of Node.js Use node -v to check it, is the version >= 14?

Install dependencies:

npm install

Build the static content:

npm run build

Deploy

Change directory to deploy/terraform:

cd $BASE_DIR/deploy/terraform

Skip this step for OCI Cloud Shell: Authenticate with OCI, it will open a browser where you can log in:

oci session authenticate

Input the region (Frankfurt by default), and the session name (DEFAULT for Cloud Shell).

Terraform will read the values from a file terraform.tfvars that you are going to create in the next step.

Use terraform variables template file to create your own terraform.tfvars:

cp terraform.tfvars.template terraform.tfvars

Edit the variables values with vim or your favorite editor:

vim terraform.tfvars

The values goes in this file terraform.tfvars and contains: profile, tenancy, compartment and ssh key.

Profile

The config_file_profile is DEFAULT if you are using OCI Cloud Shell.

But if you use oci session authenticate (not for OCI Cloud Shell) you might have specify a different value, change it in that case.

Tenancy

The tenancy_ocid value comes from the account tenancy OCID, get the value with the following command:

echo $OCI_TENANCY

Compartment

For testing, you can use the root compartment, what is the tenancy OCID from the previous step.

Sometimes, you want a specific compartment. To get the compartment OCID you can run a search with the following command:

Replace NAME_TO_FIND for the name of the compartment

oci iam compartment list \
  --compartment-id-in-subtree true \
  --name NAME_TO_FIND | jq .data

SSH Public key

The ssh_public_key is for your public SSH key, you can copy the result of:

cat ~/.ssh/id_rsa.pub

Do you have an SSH key pair, if not, run the following command:

ssh-keygen -b 2048 -t rsa

Then, you can copy the result of: cat ~/.ssh/id_rsa.pub

Terraform

Initialize the terraform provider:

terraform init

Plan the infrastructure:

terraform plan -out resources.tfplan

Apply the infrastructure, based on the plan from the previous step:

terraform apply resources.tfplan

Answer by typing yes when terraform asks you to confirm.

Curious about what it looks like? Terraform can generate a graph.

Generate the graph of resources created:

terraform graph

Ansible

Ansible SSH into the machines and provision everything needed for the machines to host the applications:

• Frontend: NGINX and static content for the frontend
• Backend: Python app as Systemd Service and database parameters

Run the Ansible Playbook:

ansible-playbook -i generated/app.ini \
  ../ansible/site.yaml \
  --extra-vars "@generated/backend_params.json"

NOTE: You will be asked a few times: Are you sure you want to continue connecting (yes/no/[fingerprint])? Type yes and [ENTER].

Print the load balancer IP from the terraform output again:

terraform output lb_public_ip

Copy and paste the IP on your browser.

You will see:

Click GET TIME to get a date from the backend, that will ask the database.

Clean Up

Destroy all the infrastructure:

terraform destroy -auto-approve