From 33ca6c9c17f5f1cd7cb282bb06976a74d4baa194 Mon Sep 17 00:00:00 2001
From: Jari Kolehmainen <jari.kolehmainen@gmail.com>
Date: Thu, 22 Apr 2021 07:18:53 +0300
Subject: [PATCH] Reserve cluster proxy port just in time (#2554)

* reserve cluster proxy port just in time

Signed-off-by: Jari Kolehmainen <jari.kolehmainen@gmail.com>

* fix

Signed-off-by: Jari Kolehmainen <jari.kolehmainen@gmail.com>

* refactor

Signed-off-by: Jari Kolehmainen <jari.kolehmainen@gmail.com>
---
 src/main/__test__/kubeconfig-manager.test.ts |  8 ++-
 src/main/cluster.ts                          |  2 +-
 src/main/kubeconfig-manager.ts               | 59 ++++++++++----------
 3 files changed, 35 insertions(+), 34 deletions(-)

diff --git a/src/main/__test__/kubeconfig-manager.test.ts b/src/main/__test__/kubeconfig-manager.test.ts
index 5ae7681d37..cf93f71957 100644
--- a/src/main/__test__/kubeconfig-manager.test.ts
+++ b/src/main/__test__/kubeconfig-manager.test.ts
@@ -76,7 +76,7 @@ describe("kubeconfig manager tests", () => {
     });
     const contextHandler = new ContextHandler(cluster);
     const port = await getFreePort();
-    const kubeConfManager = await KubeconfigManager.create(cluster, contextHandler, port);
+    const kubeConfManager = new KubeconfigManager(cluster, contextHandler, port);
 
     expect(logger.error).not.toBeCalled();
     expect(await kubeConfManager.getPath()).toBe(`tmp${path.sep}kubeconfig-foo`);
@@ -98,13 +98,15 @@ describe("kubeconfig manager tests", () => {
     });
     const contextHandler = new ContextHandler(cluster);
     const port = await getFreePort();
-    const kubeConfManager = await KubeconfigManager.create(cluster, contextHandler, port);
+    const kubeConfManager = new KubeconfigManager(cluster, contextHandler, port);
     const configPath = await kubeConfManager.getPath();
 
     expect(await fse.pathExists(configPath)).toBe(true);
     await kubeConfManager.unlink();
     expect(await fse.pathExists(configPath)).toBe(false);
     await kubeConfManager.unlink(); // doesn't throw
-    expect(await kubeConfManager.getPath()).toBeUndefined();
+    expect(async () => {
+      await kubeConfManager.getPath();
+    }).rejects.toThrow("already unlinked");
   });
 });
diff --git a/src/main/cluster.ts b/src/main/cluster.ts
index c7a142cc30..6606a71605 100644
--- a/src/main/cluster.ts
+++ b/src/main/cluster.ts
@@ -294,7 +294,7 @@ export class Cluster implements ClusterModel, ClusterState {
     try {
       this.initializing = true;
       this.contextHandler = new ContextHandler(this);
-      this.kubeconfigManager = await KubeconfigManager.create(this, this.contextHandler, port);
+      this.kubeconfigManager = new KubeconfigManager(this, this.contextHandler, port);
       this.kubeProxyUrl = `http://localhost:${port}${apiKubePrefix}`;
       this.initialized = true;
       logger.info(`[CLUSTER]: "${this.contextName}" init success`, {
diff --git a/src/main/kubeconfig-manager.ts b/src/main/kubeconfig-manager.ts
index f88ce87840..6fe5cddf39 100644
--- a/src/main/kubeconfig-manager.ts
+++ b/src/main/kubeconfig-manager.ts
@@ -9,16 +9,39 @@ import logger from "./logger";
 
 export class KubeconfigManager {
   protected configDir = app.getPath("temp");
-  protected tempFile: string;
+  protected tempFile: string = null;
 
-  private constructor(protected cluster: Cluster, protected contextHandler: ContextHandler, protected port: number) { }
+  constructor(protected cluster: Cluster, protected contextHandler: ContextHandler, protected port: number) { }
 
-  static async create(cluster: Cluster, contextHandler: ContextHandler, port: number) {
-    const kcm = new KubeconfigManager(cluster, contextHandler, port);
+  async getPath(): Promise<string> {
+    if (this.tempFile === undefined) {
+      throw new Error("kubeconfig is already unlinked");
+    }
 
-    await kcm.init();
+    if (!this.tempFile) {
+      await this.init();
+    }
 
-    return kcm;
+    // create proxy kubeconfig if it is removed without unlink called
+    if (!(await fs.pathExists(this.tempFile))) {
+      try {
+        this.tempFile = await this.createProxyKubeconfig();
+      } catch (err) {
+        logger.error(`Failed to created temp config for auth-proxy`, { err });
+      }
+    }
+
+    return this.tempFile;
+  }
+
+  async unlink() {
+    if (!this.tempFile) {
+      return;
+    }
+
+    logger.info(`Deleting temporary kubeconfig: ${this.tempFile}`);
+    await fs.unlink(this.tempFile);
+    this.tempFile = undefined;
   }
 
   protected async init() {
@@ -30,20 +53,6 @@ export class KubeconfigManager {
     }
   }
 
-  async getPath() {
-    // create proxy kubeconfig if it is removed
-    if (this.tempFile !== undefined && !(await fs.pathExists(this.tempFile))) {
-      try {
-        this.tempFile = await this.createProxyKubeconfig();
-      } catch (err) {
-        logger.error(`Failed to created temp config for auth-proxy`, { err });
-      }
-    }
-
-    return this.tempFile;
-
-  }
-
   protected resolveProxyUrl() {
     return `http://127.0.0.1:${this.port}/${this.cluster.id}`;
   }
@@ -87,14 +96,4 @@ export class KubeconfigManager {
 
     return tempFile;
   }
-
-  async unlink() {
-    if (!this.tempFile) {
-      return;
-    }
-
-    logger.info(`Deleting temporary kubeconfig: ${this.tempFile}`);
-    await fs.unlink(this.tempFile);
-    this.tempFile = undefined;
-  }
 }