Merge pull request #2526 from github/henrymercer/check-zstd-on-path

Check zstd is on the path in addition to tar version

src/tar.ts

@@ -18,6 +18,20 @@ export type TarVersion = {
  version: string;
 };
 
+async function isBinaryAccessible(
+ binary: string,
+ logger: Logger,
+): Promise<boolean> {
+ try {
+ await safeWhich(binary);
+ logger.debug(`Found ${binary}.`);
+ return true;
+ } catch (e) {
+ logger.debug(`Could not find ${binary}: ${e}`);
+ return false;
+ }
+}
+
 async function getTarVersion(): Promise<TarVersion> {
  const tar = await safeWhich("tar");
  let stdout = "";
@@ -53,36 +67,40 @@ async function getTarVersion(): Promise<TarVersion> {
 
 export interface ZstdAvailability {
  available: boolean;
+ foundZstdBinary: boolean;
  version?: TarVersion;
 }
 
 export async function isZstdAvailable(
  logger: Logger,
 ): Promise<ZstdAvailability> {
+ const foundZstdBinary = await isBinaryAccessible("zstd", logger);
  try {
  const tarVersion = await getTarVersion();
  const { type, version } = tarVersion;
  logger.info(`Found ${type} tar version ${version}.`);
  switch (type) {
  case "gnu":
  return {
- available: version >= MIN_REQUIRED_GNU_TAR_VERSION,
+ available: foundZstdBinary && version >= MIN_REQUIRED_GNU_TAR_VERSION,
+ foundZstdBinary,
  version: tarVersion,
  };
  case "bsd":
  return {
- available: version >= MIN_REQUIRED_BSD_TAR_VERSION,
+ available: foundZstdBinary && version >= MIN_REQUIRED_BSD_TAR_VERSION,
+ foundZstdBinary,
  version: tarVersion,
  };
  default:
  assertNever(type);
  }
  } catch (e) {
- logger.error(
- "Failed to determine tar version, therefore will assume zstd may not be available. " +
+ logger.warning(
+ "Failed to determine tar version, therefore will assume zstd is not available. " +
  `The underlying error was: ${e}`,
  );
- return { available: false };
+ return { available: false, foundZstdBinary };
  }
 }