The Secret Weapon for DevOps Success: Creating an Application in Argo CD Using Terraform

Overview :-

In today’s fast-paced world of software development, #DevOps practices have become essential for organizations to deliver high-quality applications quickly and efficiently. One powerful combination that has gained popularity among #DevOps teams is the use of #Argo CD and Terraform. This blog post will guide you through the process of creating an application in #Argo CD using #Terraform, a method that can significantly improve your #DevOps workflow.

#Argo CD is a declarative, #GitOps continuous delivery tool for Kubernetes, while Terraform is an infrastructure-as-code tool that allows you to define and provision infrastructure resources. By combining these two technologies, you can automate the deployment and management of your applications in a #Kubernetes environment, making your #DevOps processes more efficient and reliable.

Prerequisites :-

Before we dive into the procedure, make sure you have the following prerequisites in place:

1. A #Kubernetes cluster
2. Argo CD installed on your cluster
3. Terraform installed on your local machine
4. Basic knowledge of Kubernetes, #Argo CD, and #Terraform
5. A #Git repository to store your application manifests and Terraform configuration

Having these elements ready will ensure a smooth experience as we go through the steps of creating an application in #Argo CD using Terraform.

Procedure :-

Let’s break down the process into manageable steps:

Step 1: Set up your #Terraform configuration

1. Create a new directory for your Terraform configuration:

mkdir argocd-app-terraform
cd argocd-app-terraform

1. Create a main.tf file with the following content:

data "aws_eks_cluster" "default" {
  name = "mahira-eks-cluster"
}

data "aws_eks_cluster_auth" "default" {
  name = "mahira-eks-cluster"
}

provider "kubernetes" {
  host                   = data.aws_eks_cluster.default.endpoint
  cluster_ca_certificate = base64decode(data.aws_eks_cluster.default.certificate_authority.0.data)
  token                  = data.aws_eks_cluster_auth.default.token
}

resource "kubernetes_manifest" "mahira_app" {
  manifest = {
    "apiVersion" = "argoproj.io/v1alpha1"
    "kind" = "Application"
    "metadata" = {
      "finalizers" = [
        "resources-finalizer.argocd.argoproj.io",
      ]
      "name" = "mahira-k8s"
      "namespace" = "argocd"
    }
    "spec" = {
      "destination" = {
        "namespace" = "default"
        "server" = "https://kubernetes.default.svc"
      }
      "project" = "mahira-app"
      "source" = {
        "path" = "bases/mahira-app"
        "repoURL" = "https://github.com/MahiraTechnology/mahira-k8s.git"
        "targetRevision" = "HEAD"
      }
    }
  }
}

resource "kubernetes_manifest" "mahira_project" {
  manifest = {
    "apiVersion" = "argoproj.io/v1alpha1"
    "kind" = "AppProject"
    "metadata" = {
      "finalizers" = [
        "resources-finalizer.argocd.argoproj.io",
      ]
      "name" = "mahira-project"
      "namespace" = "argocd"
    }
    "spec" = {
      "clusterResourceWhitelist" = [
        {
          "group" = "*"
          "kind" = "*"
        },
      ]
      "description" = "mahira Project"
      "destinations" = [
        {
          "namespace" = "default"
          "server" = "https://kubernetes.default.svc"
        },
      ]
      "namespaceResourceBlacklist" = []
      "namespaceResourceWhitelist" = [
        {
          "group" = "*"
          "kind" = "*"
        },
      ]
      "roles" = [{
        "name" = "admin"
        "policies" = [
           "p, proj:mahira-app:admin, applications, create, mahira-app/*, allow",
           "p, proj:mahira-app:admin, applications, update, mahira-app/*, allow",
           "p, proj:mahira-app:admin, applications, delete, mahira-app/*, allow",
        ]
      },
      ]
      "sourceRepos" = [
        "*",
      ]
    }
  }
}

2. Create a provider.tf file with following content.

terraform {
  required_providers {
    kubernetes = {
      source = "hashicorp/kubernetes"
      version = "2.32.0"
    }
  }
}

Make sure to replace argocd.example.com:443 with your #Argo CD server address, your-argocd-auth-token with your actual #Argo CD authentication token, and update the repo_url to point to your application's Git repository.

Step 2: Initialize and apply #Terraform configuration

1. Initialize #Terraform:

terraform init

1. Review the planned changes:

terraform plan

1. Apply the configuration:

terraform apply

Step 3: Verify the application in Argo CD

1. Log in to your #Argo CD web interface.
2. Navigate to the Applications page.
3. You should see your newly created application “mahira-app” listed.
4. Click on the application to view its details and sync status.

Step 4: Make changes and update the application

1. Make changes to your application code or #Kubernetes manifests in your #Git repository.
2. Commit and push the changes to the main branch.
3. #Argo CD will automatically detect the changes and sync the application.

Conclusion :-

By adopting this method, you can improve your #DevOps workflow, increase efficiency, and maintain better control over your application deployments. As you become more comfortable with this approach, you can explore more advanced features of both #Argo CD and #Terraform to further enhance your #DevOps practices.

Remember, the key to success in #DevOps is continuous learning and improvement. Keep exploring new tools and techniques to stay ahead in the ever-evolving world of software development and operations.