Added new exception class to reveal more information to the user. Fixes

#34

hpcpy/client/base.py

@@ -115,7 +115,6 @@ def status(self, job_id):
         job_id : str
             Job ID.
         """
-        # raise NotImplementedError()
         cmd = self._tmp_status.format(job_id=job_id)
         result = self._shell(cmd)
         return result
@@ -171,11 +170,15 @@ def _shell(self, cmd, decode=True):
             Command to run.
         decode : bool
             Automatically decode response with utf-8, defaults to True
+        Raises
+        ------
+        hpcypy.excetions.ShellException :
+            When the underlying shell call fails.
 
         Returns
         -------
-        _type_
-            _description_
+        str
+            Result from the underlying called command.
         """
         result = shell(cmd)
 

hpcpy/exceptions.py

@@ -1,5 +1,36 @@
+import subprocess as sp
+
+
 class NoClientException(Exception):
     def __init__(self):
         super().__init__(
             "Unable to detect scheduler type, cannot determine client type."
         )
+
+
+class ShellException(Exception):
+    """Exception class to improve readability of the subprocess.CalledProcessError"""
+
+    def __init__(self, called_process_error: sp.CalledProcessError):
+        """Constructor
+
+        Parameters
+        ----------
+        called_process_error : sp.CalledProcessError
+            Source subprocess.CalledError
+        """
+        self.returncode = called_process_error.returncode
+        self.cmd = called_process_error.cmd[0]
+        self.stdout = called_process_error.stdout.decode()
+        self.stderr = called_process_error.stderr.decode()
+        self.output = called_process_error.output
+
+    def __str__(self):
+        """Improved string representation of the error message.
+
+        Returns
+        -------
+        str
+            Improved error messaging
+        """
+        return f"Error {self.returncode}: {self.stderr}"

hpcpy/utilities.py

@@ -5,6 +5,7 @@
 import jinja2.meta as j2m
 from pathlib import Path
 from importlib import resources
+from hpcpy.exceptions import ShellException
 import shlex
 
 
@@ -27,11 +28,19 @@ def shell(cmd, check=True, capture_output=True, **kwargs) -> sp.CompletedProcess
 
     Raises
     ------
-    subprocess.CalledProcessError
+    hpcypy.excetions.ShellException :
+        When the shell call fails.
     """
-    return sp.run(
-        shlex.split(cmd), check=check, capture_output=capture_output, **kwargs
-    )
+    try:
+        return sp.run(
+            shlex.split(cmd),
+            shell=True,
+            check=check,
+            capture_output=capture_output,
+            **kwargs,
+        )
+    except sp.CalledProcessError as ex:
+        raise ShellException(ex)
 
 
 def interpolate_string_template(template, **kwargs) -> str:

tests/test_utilities.py

@@ -1,8 +1,17 @@
 """Tests for utilities.py"""
 
 import hpcpy.utilities as hu
+import hpcpy.exceptions as hx
 
 
 def test_interpolate_string_template():
     """Test interpolating a string template."""
     assert hu.interpolate_string_template("hello {{arg}}", arg="world") == "hello world"
+
+
+def test_shell_exception():
+    """Test that error messaging is being raised to the user."""
+    try:
+        hu.shell("blah")
+    except hx.ShellException as ex:
+        assert ex.__str__() == "Error 127: /bin/sh: blah: command not found\n"