Add detected tar version to telemetry

src/init-action.ts

@@ -42,6 +42,7 @@ import {
   getActionsStatus,
   sendStatusReport,
 } from "./status-report";
+import { isZstdAvailable } from "./tar";
 import { ToolsFeature } from "./tools-features";
 import { getTotalCacheSize } from "./trap-caching";
 import {
@@ -375,6 +376,8 @@ async function run() {
   try {
     cleanupDatabaseClusterDirectory(config, logger);
 
+    await logZstdAvailability(config, logger);
+
     // Log CodeQL download telemetry, if appropriate
     if (toolsDownloadStatusReport) {
       addDiagnostic(
@@ -670,6 +673,29 @@ function getTrapCachingEnabled(): boolean {
   return true;
 }
 
+async function logZstdAvailability(config: configUtils.Config, logger: Logger) {
+  // Log zstd availability
+  const zstdAvailableResult = await isZstdAvailable(logger);
+  addDiagnostic(
+    config,
+    // Arbitrarily choose the first language. We could also choose all languages, but that
+    // increases the risk of misinterpreting the data.
+    config.languages[0],
+    makeDiagnostic(
+      "codeql-action/zstd-availability",
+      "Zstandard availability",
+      {
+        attributes: zstdAvailableResult,
+        visibility: {
+          cliSummaryTable: false,
+          statusPage: false,
+          telemetry: true,
+        },
+      },
+    ),
+  );
+}
+
 async function runWrapper() {
   try {
     await run();

src/tar.ts

@@ -8,7 +8,7 @@ import { assertNever } from "./util";
 const MIN_REQUIRED_BSD_TAR_VERSION = "3.4.3";
 const MIN_REQUIRED_GNU_TAR_VERSION = "1.31";
 
-type TarVersion = {
+export type TarVersion = {
   type: "gnu" | "bsd";
   version: string;
 };
@@ -46,15 +46,24 @@ async function getTarVersion(): Promise<TarVersion> {
   }
 }
 
-export async function isZstdAvailable(logger: Logger): Promise<boolean> {
+export async function isZstdAvailable(
+  logger: Logger,
+): Promise<{ available: boolean; version?: TarVersion }> {
   try {
-    const { type, version } = await getTarVersion();
+    const tarVersion = await getTarVersion();
+    const { type, version } = tarVersion;
     logger.info(`Found ${type} tar version ${version}.`);
     switch (type) {
       case "gnu":
-        return version >= MIN_REQUIRED_GNU_TAR_VERSION;
+        return {
+          available: version >= MIN_REQUIRED_GNU_TAR_VERSION,
+          version: tarVersion,
+        };
       case "bsd":
-        return version >= MIN_REQUIRED_BSD_TAR_VERSION;
+        return {
+          available: version >= MIN_REQUIRED_BSD_TAR_VERSION,
+          version: tarVersion,
+        };
       default:
         assertNever(type);
     }
@@ -63,7 +72,7 @@ export async function isZstdAvailable(logger: Logger): Promise<boolean> {
       "Failed to determine tar version, therefore will assume zstd may not be available. " +
         `The underlying error was: ${e}`,
     );
-    return false;
+    return { available: false };
   }
 }