fix: handle if tar fails to extract contents nhc tarball

Previously, if tar failed to extract the contents of the nhc
tarball to `/tmp/nhc`, _install_nhc_from_tarball would throw
an unhandled excepting that would cause the charm to bork.

Now we catch if tar fails to extract the contents of the tarball,
log the error output for the asministrator to read, and return False
so that the slurmd operator can properly handle and install failure.

Signed-off-by: Jason C. Nucciarone <[email protected]>

src/slurmd_ops.py

@@ -173,7 +173,12 @@ def _install_nhc_from_tarball(self) -> bool:
         base_path.mkdir()
 
         cmd = f"tar --extract --directory {base_path} --file lbnl-nhc-1.4.3.tar.gz".split()
-        subprocess.run(cmd)
+        try:
+            result = subprocess.check_output(cmd, stderr=subprocess.STDOUT, text=True)
+            logger.debug(result)
+        except subprocess.CalledProcessError as e:
+            logger.error("failed to extract NHC using tar. reason:\n%s", e.stdout)
+            return False
 
         full_path = base_path / os.listdir(base_path)[0]