From b910c7d63de07db50b037ec0a31345ba8a4d08e9 Mon Sep 17 00:00:00 2001
From: Krishna Chilleri <krishnachilleri@gmail.com>
Date: Fri, 11 Oct 2024 15:15:21 -0600
Subject: [PATCH] allow beeflow to run on back end node + documentation

---
 beeflow/client/core.py   | 15 ++++++++++-----
 docs/sphinx/commands.rst |  1 +
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/beeflow/client/core.py b/beeflow/client/core.py
index 49fd7cdd..a468b3cc 100644
--- a/beeflow/client/core.py
+++ b/beeflow/client/core.py
@@ -296,14 +296,15 @@ def load_check_charliecloud():
         sys.exit(1)
 
 
-def check_dependencies():
+def check_dependencies(backend=False):
     """Check for various dependencies in the environment."""
-    print('Checking dependencies...')
     # Check if running on compute node under Slurm scheduler
-    if os.environ.get('SLURM_JOB_NODELIST') is not None:
+    if not backend and os.environ.get('SLURM_JOB_NODELIST') is not None:
         warn('Slurm job node detected! Beeflow should not be run on a compute node.')
         warn(f'SLURM_JOB_NODELIST = {os.environ.get("SLURM_JOB_NODELIST")}')
         sys.exit(1)
+        
+    print('Checking dependencies...')
     # Check for Charliecloud and its version
     load_check_charliecloud()
     # Check for the flux API
@@ -385,9 +386,13 @@ def handle_terminate(signum, stack): # noqa
 
 @app.command()
 def start(foreground: bool = typer.Option(False, '--foreground', '-F',
-          help='run in the foreground')):
+          help='run in the foreground'), backend: bool = typer.Option(False, '--backend', 
+          '-B', help='allow to run on a backend node')):
     """Start all BEE components."""
-    check_dependencies()
+    if backend:  # allow beeflow to run on backend node
+        check_dependencies(backend=True)
+    else:
+        check_dependencies()
     mgr = init_components()
     beeflow_log = paths.log_fname('beeflow')
     sock_path = paths.beeflow_socket()
diff --git a/docs/sphinx/commands.rst b/docs/sphinx/commands.rst
index 7b44db5a..a51822da 100644
--- a/docs/sphinx/commands.rst
+++ b/docs/sphinx/commands.rst
@@ -14,6 +14,7 @@ To interact with the daemon process you'll need to use the ``beeflow core`` sub-
 
 Options:
   -F, --foreground  run in the foreground  [default: False]
+  -B, --backend  run on a back end node  [default: False]
 
 
 ``beeflow core status``: Check the status of beeflow and the components.