chore/k8s-single-node-k3s via Terraform

Se connecte à la machine on-premise via SSH et installe k3s single-node puis instancie le module.

apply reste à faire une fois la machine prête.

infra/terraform/environments/dev/main.tf

@@ -0,0 +1,11 @@
+module "k3s" {
+  source = "../../modules/k3s"
+
+  ssh_host               = var.ssh_host
+  ssh_port               = var.ssh_port
+  ssh_user               = var.ssh_user
+  ssh_private_key_path   = var.ssh_private_key_path
+  k3s_version            = var.k3s_version
+  k3s_disable_components = var.k3s_disable_components
+  kubeconfig_output_path = var.kubeconfig_output_path
+}

infra/terraform/environments/dev/outputs.tf

@@ -0,0 +1,9 @@
+output "kubeconfig_path" {
+  description = "Chemin local du kubeconfig recupere apres installation."
+  value       = module.k3s.kubeconfig_path
+}
+
+output "node_host" {
+  description = "Adresse du serveur sur lequel k3s est installe."
+  value       = module.k3s.node_host
+}

infra/terraform/environments/dev/terraform.tfvars.example

@@ -0,0 +1,7 @@
+ssh_host                = "10.0.0.10"
+ssh_port                = 22
+ssh_user                = "root"
+ssh_private_key_path    = "~/.ssh/id_ed25519_enervision"
+k3s_version             = ""
+k3s_disable_components  = ["traefik"]
+kubeconfig_output_path  = "./kubeconfig"

infra/terraform/environments/dev/variables.tf

@@ -0,0 +1,40 @@
+variable "ssh_host" {
+  type        = string
+  description = "Adresse IP ou nom d'hote du serveur on-premise de l'ecole."
+}
+
+variable "ssh_port" {
+  type        = number
+  description = "Port SSH du serveur."
+  default     = 22
+}
+
+variable "ssh_user" {
+  type        = string
+  description = "Utilisateur SSH utilise pour l'installation."
+  default     = "root"
+}
+
+variable "ssh_private_key_path" {
+  type        = string
+  description = "Chemin local vers la cle privee SSH."
+  sensitive   = true
+}
+
+variable "k3s_version" {
+  type        = string
+  description = "Version k3s a installer. Chaine vide = derniere version stable."
+  default     = ""
+}
+
+variable "k3s_disable_components" {
+  type        = list(string)
+  description = "Composants embarques k3s a desactiver."
+  default     = ["traefik"]
+}
+
+variable "kubeconfig_output_path" {
+  type        = string
+  description = "Chemin local ou ecrire le kubeconfig recupere apres installation."
+  default     = "./kubeconfig"
+}

infra/terraform/environments/dev/versions.tf

@@ -0,0 +1,14 @@
+terraform {
+  required_version = ">= 1.7"
+
+  required_providers {
+    null = {
+      source  = "hashicorp/null"
+      version = "~> 3.2"
+    }
+  }
+
+  backend "local" {
+    path = "terraform.tfstate"
+  }
+}

infra/terraform/modules/k3s/main.tf

@@ -0,0 +1,45 @@
+locals {
+  sudo_prefix    = var.ssh_user == "root" ? "" : "sudo "
+  install_env    = var.k3s_version != "" ? "INSTALL_K3S_VERSION=${var.k3s_version} " : ""
+  disable_flags  = join(" ", [for c in var.k3s_disable_components : "--disable=${c}"])
+  kubeconfig_cmd = "${local.sudo_prefix}cat /etc/rancher/k3s/k3s.yaml"
+}
+
+resource "null_resource" "k3s_install" {
+  triggers = {
+    ssh_host            = var.ssh_host
+    k3s_version         = var.k3s_version
+    disable_components  = join(",", var.k3s_disable_components)
+  }
+
+  connection {
+    type        = "ssh"
+    host        = var.ssh_host
+    port        = var.ssh_port
+    user        = var.ssh_user
+    private_key = file(var.ssh_private_key_path)
+  }
+
+  provisioner "remote-exec" {
+    inline = [
+      "${local.sudo_prefix}sh -c 'curl -sfL https://get.k3s.io | ${local.install_env}sh -s - server --write-kubeconfig-mode 644 ${local.disable_flags}'",
+      "until ${local.sudo_prefix}test -f /etc/rancher/k3s/k3s.yaml; do sleep 2; done",
+    ]
+  }
+}
+
+resource "null_resource" "fetch_kubeconfig" {
+  depends_on = [null_resource.k3s_install]
+
+  triggers = {
+    install_id = null_resource.k3s_install.id
+  }
+
+  provisioner "local-exec" {
+    interpreter = ["bash", "-c"]
+    command     = <<-EOT
+      ssh -i "${var.ssh_private_key_path}" -p ${var.ssh_port} -o StrictHostKeyChecking=accept-new ${var.ssh_user}@${var.ssh_host} '${local.kubeconfig_cmd}' \
+        | sed 's/127.0.0.1/${var.ssh_host}/' > "${var.kubeconfig_output_path}"
+    EOT
+  }
+}

infra/terraform/modules/k3s/outputs.tf

@@ -0,0 +1,9 @@
+output "kubeconfig_path" {
+  description = "Chemin local du kubeconfig recupere apres installation."
+  value       = var.kubeconfig_output_path
+}
+
+output "node_host" {
+  description = "Adresse de la machine sur laquelle k3s est installe."
+  value       = var.ssh_host
+}

infra/terraform/modules/k3s/variables.tf

@@ -0,0 +1,39 @@
+variable "ssh_host" {
+  type        = string
+  description = "Adresse IP ou nom d'hote de la machine on-premise cible."
+}
+
+variable "ssh_port" {
+  type        = number
+  description = "Port SSH de la machine cible."
+  default     = 22
+}
+
+variable "ssh_user" {
+  type        = string
+  description = "Utilisateur SSH. Si different de root, les commandes d'installation sont prefixees par sudo."
+  default     = "root"
+}
+
+variable "ssh_private_key_path" {
+  type        = string
+  description = "Chemin local vers la cle privee SSH utilisee pour se connecter a la machine cible."
+  sensitive   = true
+}
+
+variable "k3s_version" {
+  type        = string
+  description = "Version k3s a installer (ex: v1.31.2+k3s1). Chaine vide = derniere version stable."
+  default     = ""
+}
+
+variable "k3s_disable_components" {
+  type        = list(string)
+  description = "Composants embarques a desactiver a l'installation (ex: traefik, servicelb)."
+  default     = ["traefik"]
+}
+
+variable "kubeconfig_output_path" {
+  type        = string
+  description = "Chemin local ou ecrire le kubeconfig recupere apres installation."
+}

infra/terraform/modules/k3s/versions.tf

@@ -0,0 +1,10 @@
+terraform {
+  required_version = ">= 1.7"
+
+  required_providers {
+    null = {
+      source  = "hashicorp/null"
+      version = "~> 3.2"
+    }
+  }
+}