Add artificial resource in order to wait for cluster to be in ready s… (

#35)

* Add artificial resource in order to wait for cluster to be in ready state

This commit introduces a change that will block module completion up until created cluster is in the Ready state.

Natural candidate for cluster ready state is castai_xxx_cluster resource creation step. Hoverer as cluster resource needs to finish its creation in order to run helm charts that actually deploys components that makes cluster to transit to ready state we need to introduce custom resource that will depend on helm charts resources that will pool ready state.

To accomplish this null_resource was introduced that pools created cluster status until it is in ready state.

main.tf

@@ -216,6 +216,32 @@ resource "helm_release" "castai_cluster_controller" {
   }
 }
 
+resource "null_resource" "wait_for_cluster" {
+  count = var.wait_for_cluster_ready ? 1 : 0
+  depends_on = [helm_release.castai_cluster_controller, helm_release.castai_agent]
+
+  provisioner "local-exec" {
+    quiet = true
+    environment = {
+      API_KEY = var.castai_api_token
+    }
+    command = <<-EOT
+        RETRY_COUNT=30
+        POOLING_INTERVAL=30
+
+        for i in $(seq 1 $RETRY_COUNT); do
+            sleep $POOLING_INTERVAL
+            curl -s ${var.api_url}/v1/kubernetes/external-clusters/${castai_aks_cluster.castai_cluster.id} -H "x-api-key: $API_KEY" | grep '"status"\s*:\s*"ready"' && exit 0
+        done
+
+        echo "Cluster is not ready after 15 minutes"
+        exit 1
+    EOT
+
+    interpreter = ["bash", "-c"]
+  }
+}
+
 resource "helm_release" "castai_spot_handler" {
   name             = "castai-spot-handler"
   repository       = "https://castai.github.io/helm-charts"

variables.tf

@@ -4,6 +4,13 @@ variable "api_url" {
   default     = "https://api.cast.ai"
 }
 
+variable "castai_api_token" {
+  type = string
+  description = "Optional CAST AI API token created in console.cast.ai API Access keys section. Used only when `wait_for_cluster_ready` is set to true"
+  sensitive = true
+  default = ""
+}
+
 variable "aks_cluster_name" {
   type        = string
   description = "Name of the cluster to be connected to CAST AI."
@@ -136,3 +143,9 @@ variable "kvisor_version" {
   type        = string
   default     = null
 }
+
+variable "wait_for_cluster_ready" {
+  type        = bool
+  description = "Wait for cluster to be ready before finishing the module execution, this option requires `castai_api_token` to be set"
+  default     = false
+}