fix: prime NHC tarball within charm during packing

charmcraft.yaml

@@ -34,12 +34,16 @@ bases:
         architectures: [amd64]
 
 parts:
-  charm:
+  charm: {}
+  nhc:
+    plugin: nil
     build-packages:
       - wget
+    override-pull: |
+      wget https://github.com/mej/nhc/releases/download/1.4.3/lbnl-nhc-1.4.3.tar.gz
     override-build: |
-       wget https://github.com/mej/nhc/releases/download/1.4.3/lbnl-nhc-1.4.3.tar.gz
-       craftctl default
+      install -m644 -D -t $CRAFT_PART_INSTALL lbnl-nhc-1.4.3.tar.gz
+      craftctl default
 
 provides:
   slurmctld:

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]