Merge pull request #4294 from ashvark/real_system_username

Submitting the galaxy jobs as a predefined system user: using 'real_system_username'

config/galaxy.ini.sample

@@ -1315,7 +1315,10 @@ use_interactive = True
 # or the username which are both stored in the Galaxy data base. 
 # The latter option is particularly useful for installations that get the 
 # authentication from LDAP.
-# Possible values are user_email (default) and username.  
+# Also, Galaxy can accept the name of a common system user (eg. galaxy_worker) 
+# who can run every job being submitted. This user should not be the same user 
+# running the galaxy system. 
+# Possible values are user_email (default), username or <common_system_user>
 #real_system_username = user_email 
 
 # File to source to set up the environment when running jobs.  By default, the

lib/galaxy/model/__init__.py

@@ -204,8 +204,12 @@ class User( object, Dictifiable ):
             except KeyError:
                 pass
         else:
-            log.warning("invalid configuration of real_system_username")
-            system_user_pwent = None
+            try:
+                system_user_pwent = pwd.getpwnam(real_system_username)
+            except KeyError:
+                log.warning("invalid configuration of real_system_username")
+                system_user_pwent = None
+                pass
         return system_user_pwent
 
     def all_roles( self ):