Merge pull request #341 from pyiron/validate_backend

Add validate backend fucntion

pympipool/scheduler/__init__.py

@@ -12,8 +12,8 @@
     check_threads_per_core,
     check_oversubscribe,
     check_executor,
-    check_backend,
     check_init_function,
+    validate_backend,
     validate_number_of_cores,
 )
 from pympipool.scheduler.slurm import (
@@ -87,8 +87,10 @@ def create_executor(
     """
     max_cores = validate_number_of_cores(max_cores=max_cores, max_workers=max_workers)
     check_init_function(block_allocation=block_allocation, init_function=init_function)
-    check_backend(backend=backend)
-    if backend == "flux" or (backend == "auto" and flux_installed):
+    backend = validate_backend(
+        backend=backend, flux_installed=flux_installed, slurm_installed=slurm_installed
+    )
+    if backend == "flux":
         check_oversubscribe(oversubscribe=oversubscribe)
         check_command_line_argument_lst(
             command_line_argument_lst=command_line_argument_lst
@@ -114,7 +116,7 @@ def create_executor(
                 executor=executor,
                 hostname_localhost=hostname_localhost,
             )
-    elif backend == "slurm" or (backend == "auto" and slurm_installed):
+    elif backend == "slurm":
         check_executor(executor=executor)
         if block_allocation:
             return PySlurmExecutor(

pympipool/shared/inputcheck.py

@@ -67,14 +67,22 @@ def check_refresh_rate(refresh_rate: float):
         )
 
 
-def check_backend(backend: str):
+def validate_backend(
+    backend: str, flux_installed: bool = False, slurm_installed: bool = False
+) -> str:
     if backend not in ["auto", "mpi", "slurm", "flux"]:
         raise ValueError(
             'The currently implemented backends are ["flux", "mpi", "slurm"]. '
             'Alternatively, you can select "auto", the default option, to automatically determine the backend. But '
             + backend
             + " is not a valid choice."
         )
+    elif backend == "flux" or (backend == "auto" and flux_installed):
+        return "flux"
+    elif backend == "slurm" or (backend == "auto" and slurm_installed):
+        return "slurm"
+    else:
+        return "mpi"
 
 
 def check_init_function(block_allocation: bool, init_function: callable):

tests/test_shared_input_check.py

@@ -6,11 +6,11 @@
     check_threads_per_core,
     check_oversubscribe,
     check_executor,
-    check_backend,
     check_init_function,
     check_refresh_rate,
     check_resource_dict,
     check_resource_dict_is_empty,
+    validate_backend,
 )
 
 
@@ -37,7 +37,9 @@ def test_check_executor(self):
 
     def test_check_backend(self):
         with self.assertRaises(ValueError):
-            check_backend(backend="test")
+            validate_backend(
+                backend="test", slurm_installed=False, flux_installed=False
+            )
 
     def test_check_init_function(self):
         with self.assertRaises(ValueError):