From 12098eeeefa1f31632fd34cae2b966e477ba4ab4 Mon Sep 17 00:00:00 2001
From: Andrew Peabody <andrewpeabody@google.com>
Date: Fri, 9 Feb 2024 19:14:38 +0000
Subject: [PATCH] fix: mutex for tft init

---
 .../examples/simple_krm_blueprint/pod.yaml         |  1 -
 infra/blueprint-test/pkg/tft/terraform.go          | 14 ++++++++++++++
 .../test/krm_simple_blueprint_test.go              |  4 +++-
 infra/blueprint-test/test/setup/main.tf            |  4 ++--
 4 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/infra/blueprint-test/examples/simple_krm_blueprint/pod.yaml b/infra/blueprint-test/examples/simple_krm_blueprint/pod.yaml
index de78753e8ca8..690853cc2ab2 100644
--- a/infra/blueprint-test/examples/simple_krm_blueprint/pod.yaml
+++ b/infra/blueprint-test/examples/simple_krm_blueprint/pod.yaml
@@ -12,7 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-
 apiVersion: v1
 kind: Pod
 metadata:
diff --git a/infra/blueprint-test/pkg/tft/terraform.go b/infra/blueprint-test/pkg/tft/terraform.go
index 24647d70aa80..6b0b61fdeb71 100644
--- a/infra/blueprint-test/pkg/tft/terraform.go
+++ b/infra/blueprint-test/pkg/tft/terraform.go
@@ -24,6 +24,7 @@ import (
 	"path"
 	"path/filepath"
 	"strings"
+	"sync"
 	gotest "testing"
 	"time"
 
@@ -73,6 +74,7 @@ type TFBlueprintTest struct {
 	verify                        func(*assert.Assertions) // verify function
 	teardown                      func(*assert.Assertions) // teardown function
 	setupOutputOverrides          map[string]interface{}   // override outputs from the Setup phase
+	tftCacheMutex                 sync.RWMutex             // Mutex to protect Terraform plugin cache
 }
 
 type tftOption func(*TFBlueprintTest)
@@ -481,21 +483,33 @@ func (b *TFBlueprintTest) DefaultApply(assert *assert.Assertions) {
 
 // Init runs the default or custom init function for the blueprint.
 func (b *TFBlueprintTest) Init(assert *assert.Assertions) {
+	// allow only single write Terraform plugin cache isn't concurrent safe
+	b.tftCacheMutex.Lock()
+	defer b.tftCacheMutex.Unlock()
 	b.init(assert)
 }
 
 // Apply runs the default or custom apply function for the blueprint.
 func (b *TFBlueprintTest) Apply(assert *assert.Assertions) {
+	// allow only parallel reads as Terraform plugin cache isn't concurrent safe
+	b.tftCacheMutex.RLock()
+	defer b.tftCacheMutex.RUnlock()
 	b.apply(assert)
 }
 
 // Verify runs the default or custom verify function for the blueprint.
 func (b *TFBlueprintTest) Verify(assert *assert.Assertions) {
+	// allow only parallel reads as Terraform plugin cache isn't concurrent safe
+	b.tftCacheMutex.RLock()
+	defer b.tftCacheMutex.RUnlock()
 	b.verify(assert)
 }
 
 // Teardown runs the default or custom teardown function for the blueprint.
 func (b *TFBlueprintTest) Teardown(assert *assert.Assertions) {
+	// allow only parallel reads as Terraform plugin cache isn't concurrent safe
+	b.tftCacheMutex.RLock()
+	defer b.tftCacheMutex.RUnlock()
 	b.teardown(assert)
 }
 
diff --git a/infra/blueprint-test/test/krm_simple_blueprint_test.go b/infra/blueprint-test/test/krm_simple_blueprint_test.go
index f1098dfd80b5..38da3aa0ddaa 100644
--- a/infra/blueprint-test/test/krm_simple_blueprint_test.go
+++ b/infra/blueprint-test/test/krm_simple_blueprint_test.go
@@ -1,6 +1,7 @@
 package test
 
 import (
+	"strings"
 	"testing"
 
 	"github.com/GoogleCloudPlatform/cloud-foundation-toolkit/infra/blueprint-test/pkg/gcloud"
@@ -26,7 +27,8 @@ func TestKRMSimpleBlueprint(t *testing.T) {
 			k8sOpts := k8s.KubectlOptions{}
 			op, err := k8s.RunKubectlAndGetOutputE(t, &k8sOpts, "get", "pod", "simple-krm-blueprint", "--no-headers", "-o", "custom-columns=:metadata.name")
 			assert.NoError(err)
-			assert.Equal("simple-krm-blueprint", op)
+			result := strings.Split(op, "\n")
+			assert.Equal("simple-krm-blueprint", result[len(result)-1])
 		})
 	networkBlueprint.Test()
 }
diff --git a/infra/blueprint-test/test/setup/main.tf b/infra/blueprint-test/test/setup/main.tf
index 0f46477fab44..ebeccc0eba60 100644
--- a/infra/blueprint-test/test/setup/main.tf
+++ b/infra/blueprint-test/test/setup/main.tf
@@ -1,5 +1,5 @@
 /**
- * Copyright 2021-2023 Google LLC
+ * Copyright 2021-2024 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -64,6 +64,6 @@ resource "google_service_account_key" "key" {
 
 module "kubernetes-engine_example_simple_autopilot_public" {
   source  = "terraform-google-modules/kubernetes-engine/google//examples/simple_autopilot_public"
-  version                     = "~> 26.0"
+  version                     = "~> 30.0"
   project_id                  = module.project.project_id
 }