Update helm cache if files have been modified

Signed-off-by: Sebastian Malton <sebastian@malton.name>

src/main/helm/helm-chart-manager.ts

@@ -24,10 +24,15 @@ import v8 from "v8";
 import * as yaml from "js-yaml";
 import type { HelmRepo } from "./helm-repo-manager";
 import logger from "../logger";
-import { promiseExec } from "../promise-exec";
+import { promiseExecFile } from "../promise-exec";
 import { helmCli } from "./helm-cli";
 import type { RepoHelmChartList } from "../../common/k8s-api/endpoints/helm-charts.api";
-import { sortCharts } from "../../common/utils";
+import { iter, sortCharts } from "../../common/utils";
+
+interface ChartCacheEntry {
+  data: Buffer,
+  mtimeMs: number,
+}
 
 export interface HelmCacheFile {
   apiVersion: string;
@@ -35,7 +40,7 @@ export interface HelmCacheFile {
 }
 
 export class HelmChartManager {
-  static #cache = new Map<string, Buffer>();
+  static #cache = new Map<string, ChartCacheEntry>();
 
   private constructor(protected repo: HelmRepo) {}
 
@@ -59,16 +64,17 @@ export class HelmChartManager {
     }
   }
 
-  private async executeCommand(action: string, name: string, version?: string) {
+  private async executeCommand(args: string[], name: string, version?: string) {
     const helm = await helmCli.binaryPath();
-    const cmd = [`"${helm}" ${action} ${this.repo.name}/${name}`];
+
+    args.push(`${this.repo.name}/${name}`);
 
     if (version) {
-      cmd.push("--version", version);
+      args.push("--version", version);
     }
 
     try {
-      const { stdout } = await promiseExec(cmd.join(" "));
+      const { stdout } = await promiseExecFile(helm, args);
 
       return stdout;
     } catch (error) {
@@ -77,32 +83,36 @@ export class HelmChartManager {
   }
 
   public async getReadme(name: string, version?: string) {
-    return this.executeCommand("show readme", name, version);
+    return this.executeCommand(["show", "readme"], name, version);
   }
 
   public async getValues(name: string, version?: string) {
-    return this.executeCommand("show values", name, version);
+    return this.executeCommand(["show", "values"], name, version);
   }
 
-  protected async cachedYaml(): Promise<RepoHelmChartList> {
-    if (!HelmChartManager.#cache.has(this.repo.name)) {
-      const cacheFile = await fs.promises.readFile(this.repo.cacheFilePath, "utf-8");
-      const data = yaml.load(cacheFile) as string | number | HelmCacheFile;
+  protected async updateYamlCache() {
+    const cacheFile = await fs.promises.readFile(this.repo.cacheFilePath, "utf-8");
+    const cacheFileStats = await fs.promises.stat(this.repo.cacheFilePath);
+    const data = yaml.load(cacheFile) as string | number | HelmCacheFile;
 
-      if (typeof data !== "object" || !data) {
-        return {};
-      }
+    if (typeof data !== "object" || !data) {
+      return;
+    }
 
-      /**
-       * Do some initial preprocessing on the data, so as to avoid needing to do it later
-       * 1. Set the repo name
-       * 2. Normalize the created date
-       * 3. Filter out deprecated items
-       */
+    const { entries } = data;
 
-      const normalized = Object.fromEntries(
-        Object.entries(data.entries)
-          .map(([name, charts]) => [
+    /**
+     * Do some initial preprocessing on the data, so as to avoid needing to do it later
+     * 1. Set the repo name
+     * 2. Normalize the created date
+     * 3. Filter out deprecated items
+     */
+
+    const normalized = Object.fromEntries(
+      iter.filter(
+        iter.map(
+          Object.entries(entries),
+          ([name, charts]) => [
             name,
             sortCharts(
               charts.map(chart => ({
@@ -111,13 +121,30 @@ export class HelmChartManager {
                 repo: this.repo.name,
               })),
             ),
-          ] as const)
-          .filter(([, charts]) => !charts.every(chart => chart.deprecated))
-      );
+          ] as const
+        ),
+        ([, charts]) => !charts.every(chart => chart.deprecated),
+      )
+    );
 
-      HelmChartManager.#cache.set(this.repo.name, v8.serialize(normalized));
+    HelmChartManager.#cache.set(this.repo.name, {
+      data: v8.serialize(normalized),
+      mtimeMs: cacheFileStats.mtimeMs,
+    });
+  }
+
+  protected async cachedYaml(): Promise<RepoHelmChartList> {
+    if (!HelmChartManager.#cache.has(this.repo.name)) {
+      await this.updateYamlCache();
+    } else {
+      const newStats = await fs.promises.stat(this.repo.cacheFilePath);
+      const cacheEntry = HelmChartManager.#cache.get(this.repo.name);
+
+      if (cacheEntry.mtimeMs < newStats.mtimeMs) {
+        await this.updateYamlCache();
+      }
     }
 
-    return v8.deserialize(HelmChartManager.#cache.get(this.repo.name));
+    return v8.deserialize(HelmChartManager.#cache.get(this.repo.name).data);
   }
 }