DUNE-DAQ · bieryAtFnal · Jul 14, 2026 · Jul 14, 2026 · Jul 14, 2026
diff --git a/python/daqconf/get_session_env_var.py b/python/daqconf/get_session_env_var.py
@@ -0,0 +1,45 @@
+import conffwk
+import confmodel_dal
+import sys
+
+def get_session_env_var(oksfile, session_name, requested_env_var_name):
+    """Script to get the value of an environment variable in the specified Session of the
+    specified OKS database file"""
+    db = conffwk.Configuration("oksconflibs:" + oksfile)
+    if session_name == "":
+        print(f"Error: the session name needs to be specified", file=sys.stderr)
+        return
+    else:
+        try:
+            session = db.get_dal("Session", session_name)
+        except:
+            print(f"Error: could not find Session \"{session_name}\" in file \"{oksfile}\"", file=sys.stderr)
+            return
+
+    schemafiles = [
+        "schema/confmodel/dunedaq.schema.xml"
+    ]
+    dal = conffwk.dal.module("dal", schemafiles)
+
+    # Check if the requested env var is defined for the specified OKS Session
+    existing_env_var = None
+    for entry in session.environment:
+        if isinstance(entry, dal.VariableSet):
+            for subentry in entry.contains:
+                if subentry.name == requested_env_var_name:
+                    existing_env_var = subentry
+                    break
+        else:
+            if entry.name == requested_env_var_name:
+                existing_env_var = entry
+
+        if existing_env_var is not None:
+            break
+
+    # Return the value, or complain and return None if the env var was not found
+    if existing_env_var is None:
+        print(f"Error: could not find env var \"{requested_env_var_name}\" in Session \"{session_name}\"", file=sys.stderr)
+        return
+    else:
+        value = existing_env_var.value
+        return value
diff --git a/python/daqconf/set_session_env_var.py b/python/daqconf/set_session_env_var.py
@@ -1,18 +1,19 @@
 import conffwk
 import confmodel_dal
+import sys
 
 def set_session_env_var(oksfile, session_name, requested_env_var_name, requested_env_var_value, overwrite=True):
     """Script to set the value of an environment variable in the specified Session of the
     specified OKS database file"""
     db = conffwk.Configuration("oksconflibs:" + oksfile)
     if session_name == "":
-        print(f"Error: the session name needs to be specified")
+        print(f"Error: the session name needs to be specified", file=sys.stderr)
         return
     else:
         try:
             session = db.get_dal("Session", session_name)
         except:
-            print(f"Error could not find Session {session_name} in file {oksfile}")
+            print(f"Error: could not find Session \"{session_name}\" in file \"{oksfile}\"", file=sys.stderr)
             return
 
     schemafiles = [
@@ -27,12 +28,10 @@ def set_session_env_var(oksfile, session_name, requested_env_var_name, requested
             for subentry in entry.contains:
                 if subentry.name == requested_env_var_name:
                     existing_env_var = subentry
-                    existing_env_var.value = requested_env_var_value
                     break
         else:
             if entry.name == requested_env_var_name:
                 existing_env_var = entry
-                existing_env_var.value = requested_env_var_value
 
         if existing_env_var is not None:
             break
@@ -43,6 +42,7 @@ def set_session_env_var(oksfile, session_name, requested_env_var_name, requested
 
     # if we found an existing env var, update the DB with the new value
     if existing_env_var is not None:
+        existing_env_var.value = requested_env_var_value
         db.update_dal(existing_env_var)
 
     # otherwise, create a new env var and assign it to the OKS Session

diff --git a/scripts/daqconf_get_session_env_var b/scripts/daqconf_get_session_env_var
@@ -0,0 +1,17 @@
+#!/bin/env python3
+import click
+from daqconf.get_session_env_var import get_session_env_var
+
+@click.command()
+@click.argument('oks_session_name')
+@click.argument('oksfile')
+@click.argument('env_var_name', required=True, nargs=1)
+def daqconf_get_session_env_var(oksfile, oks_session_name, env_var_name):
+  """Script to get the value of an environment variable in the specified Session of the
+  specified OKS database file. If the env var does not exist, '<None>' is returned."""
+  value = get_session_env_var(oksfile, oks_session_name, env_var_name)
+  if value:
+    print(value)
+
+if __name__ == '__main__':
+  daqconf_get_session_env_var()