From 76e8a58a8bd9e5b8095dd702134efdc2efc50ccc Mon Sep 17 00:00:00 2001
From: hime <jaimebz@google.com>
Date: Mon, 14 Oct 2024 22:26:45 +0000
Subject: [PATCH] Simplify injection logic.

---
 cmd/metadata_prefetch/Dockerfile |  2 +-
 pkg/webhook/injection.go         | 48 ++++++++++++++------------------
 2 files changed, 22 insertions(+), 28 deletions(-)

diff --git a/cmd/metadata_prefetch/Dockerfile b/cmd/metadata_prefetch/Dockerfile
index b94ff436..f3ccb8a4 100644
--- a/cmd/metadata_prefetch/Dockerfile
+++ b/cmd/metadata_prefetch/Dockerfile
@@ -41,4 +41,4 @@ COPY --from=debian /lib64/ld-linux-x86-64.so.2 /lib64/ld-linux-x86-64.so.2
 # Copy the built binaries
 COPY --from=metadata-prefetch-builder /bin/gcs-fuse-csi-driver-metadata-prefetch /gcs-fuse-csi-driver-metadata-prefetch
 
-ENTRYPOINT ["/gcs-fuse-csi-driver-metadata-prefetch"]
\ No newline at end of file
+ENTRYPOINT ["/gcs-fuse-csi-driver-metadata-prefetch"]
diff --git a/pkg/webhook/injection.go b/pkg/webhook/injection.go
index 2d7bee1d..1021b8aa 100644
--- a/pkg/webhook/injection.go
+++ b/pkg/webhook/injection.go
@@ -72,39 +72,33 @@ func injectSidecarContainer(pod *corev1.Pod, config *Config, supportsNativeSidec
 }
 
 func injectMetadataPrefetchSidecarContainer(pod *corev1.Pod, config *Config, supportsNativeSidecar bool) {
-	// TODO(hime): Simplify this logic, this is very repetitive at first glance.
-	if supportsNativeSidecar {
-		spec := GetNativeMetadataPrefetchSidecarContainerSpec(pod, config)
-		index := getInjectIndexAfterContainer(pod.Spec.InitContainers, SidecarContainerName)
-		if len(spec.VolumeMounts) == 0 {
-			klog.Info("no volumes are requesting metadata prefetch, skipping metadata prefetch sidecar injection...")
-
-			return
-		}
+	var containerSpec corev1.Container
+	var index int
 
-		if index == 0 {
-			klog.Warning("gke-gcsfuse-sidecar not found when attempting to inject metadata prefetch sidecar... skipping injection")
+	if supportsNativeSidecar {
+		containerSpec = GetNativeMetadataPrefetchSidecarContainerSpec(pod, config)
+		index = getInjectIndexAfterContainer(pod.Spec.InitContainers, SidecarContainerName)
+	} else {
+		containerSpec = GetMetadataPrefetchSidecarContainerSpec(pod, config)
+		index = getInjectIndexAfterContainer(pod.Spec.Containers, SidecarContainerName)
+	}
 
-			return
-		}
+	if len(containerSpec.VolumeMounts) == 0 {
+		klog.Info("no volumes are requesting metadata prefetch, skipping metadata prefetch sidecar injection...")
 
-		pod.Spec.InitContainers = insert(pod.Spec.InitContainers, spec, index)
-	} else {
-		spec := GetMetadataPrefetchSidecarContainerSpec(pod, config)
-		index := getInjectIndexAfterContainer(pod.Spec.Containers, SidecarContainerName)
-		if len(spec.VolumeMounts) == 0 {
-			klog.Info("no volumes are requesting metadata prefetch, skipping metadata prefetch sidecar injection...")
+		return
+	}
 
-			return
-		}
+	if index == 0 {
+		klog.Warning("gke-gcsfuse-sidecar not found when attempting to inject metadata prefetch sidecar... skipping injection")
 
-		if index == 0 {
-			klog.Warning("gke-gcsfuse-sidecar not found when attempting to inject metadata prefetch sidecar... skipping injection")
+		return
+	}
 
-			return
-		}
-		// Inject sidecar.
-		pod.Spec.Containers = insert(pod.Spec.Containers, spec, index)
+	if supportsNativeSidecar {
+		pod.Spec.InitContainers = insert(pod.Spec.InitContainers, containerSpec, index)
+	} else {
+		pod.Spec.Containers = insert(pod.Spec.Containers, containerSpec, index)
 	}
 }