From 9c8cc176afe7e795e263c8c2613ea52004aebe5e Mon Sep 17 00:00:00 2001
From: Bastian Krol <bastian.krol@dash0.com>
Date: Fri, 17 May 2024 13:06:27 +0200
Subject: [PATCH] test: add dedicated test for resource modifications

---
 ...suite_test.go => controller_suite_test.go} |   0
 .../k8sresources/k8sresources_suite_test.go   |  13 +++
 internal/k8sresources/modify_test.go          | 101 ++++++++++++++++++
 internal/webhook/dash0_webhook_test.go        |   5 +
 4 files changed, 119 insertions(+)
 rename internal/controller/{suite_test.go => controller_suite_test.go} (100%)
 create mode 100644 internal/k8sresources/k8sresources_suite_test.go
 create mode 100644 internal/k8sresources/modify_test.go

diff --git a/internal/controller/suite_test.go b/internal/controller/controller_suite_test.go
similarity index 100%
rename from internal/controller/suite_test.go
rename to internal/controller/controller_suite_test.go
diff --git a/internal/k8sresources/k8sresources_suite_test.go b/internal/k8sresources/k8sresources_suite_test.go
new file mode 100644
index 00000000..55f047d6
--- /dev/null
+++ b/internal/k8sresources/k8sresources_suite_test.go
@@ -0,0 +1,13 @@
+package k8sresources_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+func TestK8sresources(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "K8s Resources Suite")
+}
diff --git a/internal/k8sresources/modify_test.go b/internal/k8sresources/modify_test.go
new file mode 100644
index 00000000..24a7ed51
--- /dev/null
+++ b/internal/k8sresources/modify_test.go
@@ -0,0 +1,101 @@
+// SPDX-FileCopyrightText: Copyright 2024 Dash0 Inc.
+// SPDX-License-Identifier: Apache-2.0
+
+package k8sresources
+
+import (
+	"context"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+
+	"sigs.k8s.io/controller-runtime/pkg/log"
+
+	. "github.com/dash0hq/dash0-operator/test/util"
+)
+
+// Maintenance note: There is some overlap of test cases between this file and dash0_webhook_test.go. This is
+// intentional. However, this test should be used for more fine-grained test cases, while dash0_webhook_test.go should
+// be used to verify external effects (recording events etc.) that cannot be covered in this test.
+
+var _ = Describe("Dash0 Webhook", func() {
+
+	ctx := context.Background()
+
+	Context("when mutating new deployments", func() {
+		It("should inject Dash into a new basic deployment", func() {
+			deployment := BasicDeployment(TestNamespaceName, DeploymentName)
+			result := ModifyPodSpec(&deployment.Spec.Template.Spec, log.FromContext(ctx))
+
+			Expect(result).To(BeTrue())
+			VerifyModifiedDeployment(deployment, DeploymentExpectations{
+				Volumes:               1,
+				Dash0VolumeIdx:        0,
+				InitContainers:        1,
+				Dash0InitContainerIdx: 0,
+				Containers: []ContainerExpectations{{
+					VolumeMounts:         1,
+					Dash0VolumeMountIdx:  0,
+					EnvVars:              1,
+					NodeOptionsEnvVarIdx: 0,
+				}},
+			})
+		})
+
+		It("should inject Dash into a new deployment that has multiple Containers, and already has Volumes and init Containers", func() {
+			deployment := DeploymentWithMoreBellsAndWhistles(TestNamespaceName, DeploymentName)
+			result := ModifyPodSpec(&deployment.Spec.Template.Spec, log.FromContext(ctx))
+
+			Expect(result).To(BeTrue())
+			VerifyModifiedDeployment(deployment, DeploymentExpectations{
+				Volumes:               3,
+				Dash0VolumeIdx:        2,
+				InitContainers:        3,
+				Dash0InitContainerIdx: 2,
+				Containers: []ContainerExpectations{
+					{
+						VolumeMounts:         2,
+						Dash0VolumeMountIdx:  1,
+						EnvVars:              2,
+						NodeOptionsEnvVarIdx: 1,
+					},
+					{
+						VolumeMounts:         3,
+						Dash0VolumeMountIdx:  2,
+						EnvVars:              3,
+						NodeOptionsEnvVarIdx: 2,
+					},
+				},
+			})
+		})
+
+		It("should update existing Dash artifacts in a new deployment", func() {
+			deployment := DeploymentWithExistingDash0Artifacts(TestNamespaceName, DeploymentName)
+			result := ModifyPodSpec(&deployment.Spec.Template.Spec, log.FromContext(ctx))
+
+			Expect(result).To(BeTrue())
+			VerifyModifiedDeployment(deployment, DeploymentExpectations{
+				Volumes:               3,
+				Dash0VolumeIdx:        1,
+				InitContainers:        3,
+				Dash0InitContainerIdx: 1,
+				Containers: []ContainerExpectations{
+					{
+						VolumeMounts:             2,
+						Dash0VolumeMountIdx:      1,
+						EnvVars:                  2,
+						NodeOptionsEnvVarIdx:     1,
+						NodeOptionsUsesValueFrom: true,
+					},
+					{
+						VolumeMounts:         3,
+						Dash0VolumeMountIdx:  1,
+						EnvVars:              3,
+						NodeOptionsEnvVarIdx: 1,
+						NodeOptionsValue:     "--require /opt/dash0/instrumentation/node.js/node_modules/@dash0/opentelemetry/src/index.js --require something-else --experimental-modules",
+					},
+				},
+			})
+		})
+	})
+})
diff --git a/internal/webhook/dash0_webhook_test.go b/internal/webhook/dash0_webhook_test.go
index 72a7d534..bfe62ba3 100644
--- a/internal/webhook/dash0_webhook_test.go
+++ b/internal/webhook/dash0_webhook_test.go
@@ -9,6 +9,11 @@ import (
 	. "github.com/onsi/gomega"
 )
 
+// Maintenance note: There is some overlap of test cases between this file and k8sresources/modify_test.go. This is
+// intentional. However, this test should be used to verify external effects (recording events etc.) that cannot be
+// covered modify_test.go, while more fine-grained test cases and variations should rather be added to
+// k8sresources/modify_test.go.
+
 var _ = Describe("Dash0 Webhook", func() {
 	AfterEach(func() {
 		_ = k8sClient.Delete(ctx, BasicDeployment(TestNamespaceName, DeploymentName))