fix: use RWO for single-replica Longhorn volumes

changelogs/2.5.2.md

@@ -1,4 +1,4 @@
-# 2.5.2-rc.1
+# 2.5.2
 
 ## Fixed
 

command/main.ts

@@ -37,7 +37,7 @@ function cloneCommand<T extends object>(command: T): T {
 export const main = defineCommand({
   meta: {
     name: "kuber",
-    version: "2.5.2-rc.1",
+    version: "2.5.2",
     description: "Docker Compose -> K8s translation layer",
   },
   args: {

lib/convert.ts

@@ -1286,7 +1286,9 @@ export function volumesToPvc(
         labels: LABELS,
       },
       spec: {
-        accessModes: ["ReadWriteMany"],
+        accessModes: [
+          policy?.replicaCount === 1 ? "ReadWriteOnce" : "ReadWriteMany",
+        ],
         storageClassName: policy
           ? toLonghornStorageClassName(policy)
           : undefined,

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@dmgnr/kuber",
-  "version": "2.5.2-rc.1",
+  "version": "2.5.2",
   "description": "Docker Compose to Kubernetes translation layer",
   "bin": {
     "kuber": "dist/index.js"

tests/lib/convert-storage-env.test.ts

@@ -38,6 +38,7 @@ describe("volume conversion", () => {
     expect(claims[0]).toMatchObject({
       metadata: { name: "project-data", namespace: "project" },
       spec: {
+        accessModes: ["ReadWriteMany"],
         resources: { requests: { storage: "1Gi" } },
         storageClassName: expect.stringMatching(
           /^kuber-longhorn-[a-f0-9]{12}$/,
@@ -64,6 +65,16 @@ describe("volume conversion", () => {
     ]);
   });
 
+  test("renders single-replica Longhorn volumes as ReadWriteOnce", () => {
+    const service = { volumes: ["data(20Gi on 1 fast):/data"] } as Service;
+    const [claim] = volumesToPvc("project", service);
+    const [storageClass] = volumesToStorageClasses(service);
+
+    expect(claim?.spec?.accessModes).toEqual(["ReadWriteOnce"]);
+    expect(claim?.spec?.storageClassName).toBe(storageClass?.metadata?.name);
+    expect(storageClass?.parameters?.numberOfReplicas).toBe("1");
+  });
+
   test("parses inline storage sizing and placement", () => {
     const [claim] = volumesToPvc("project", {
       volumes: ["data(20Gi on 3 fast,archive):/data"],
@@ -71,6 +82,7 @@ describe("volume conversion", () => {
     expect(claim).toMatchObject({
       metadata: { name: "project-data" },
       spec: {
+        accessModes: ["ReadWriteMany"],
         resources: { requests: { storage: "20Gi" } },
         storageClassName: expect.stringMatching(/^kuber-longhorn-/),
       },
@@ -103,11 +115,29 @@ describe("volume conversion", () => {
       } as ComposeSpecification["volumes"],
     );
     expect(claim?.spec).toMatchObject({
+      accessModes: ["ReadWriteMany"],
       resources: { requests: { storage: "50Gi" } },
       storageClassName: expect.stringMatching(/^kuber-longhorn-/),
     });
   });
 
+  test("uses top-level single-replica policy for the PVC and StorageClass", () => {
+    const service = { volumes: ["data:/data"] } as Service;
+    const volumes = {
+      data: { "x-replicaCount": 1 },
+    } as ComposeSpecification["volumes"];
+    const [claim] = volumesToPvc("project", service, process.cwd(), volumes);
+    const [storageClass] = volumesToStorageClasses(
+      service,
+      process.cwd(),
+      volumes,
+    );
+
+    expect(claim?.spec?.accessModes).toEqual(["ReadWriteOnce"]);
+    expect(claim?.spec?.storageClassName).toBe(storageClass?.metadata?.name);
+    expect(storageClass?.parameters?.numberOfReplicas).toBe("1");
+  });
+
   test("does not create PVCs for anonymous, tmpfs, or managed claims", () => {
     expect(
       volumesToPvc("project", {