Now every subclass of ParserInterface will use the same metainfo environment...

Now every subclass of ParserInterface will use the same metainfo environment object, and not always load a new instance. Speeds things up if multiple parsers are instantiated within one python run.

common/python/nomadcore/baseclasses.py

@@ -33,6 +33,7 @@ class ParserInterface(object):
             subparsers.
     """
     __metaclass__ = ABCMeta
+    metainfo_env = None
 
     def __init__(self, main_file, metainfo_to_keep=None, backend=None, default_units=None, metainfo_units=None):
         """
@@ -62,15 +63,22 @@ class ParserInterface(object):
         if not os.path.isfile(main_file):
             logger.error("Couldn't find the main file {}. Check that the path is valid and the file exists on this path.".format(main_file))
 
-        # Load metainfo environment
-        metainfo_env, warn = load_metainfo(self.get_metainfo_filename())
-        self.parser_context.metainfo_env = metainfo_env
+        # Setup the metainfo environment. All parsers that inherit from this
+        # class will have a static class attribute that will store the metainfo
+        # environment. This way every instance of a parser doesn't have to load
+        # the environment separately because it is identical for each instance.
+        if type(self).metainfo_env is None:
+            metainfo_env, warn = load_metainfo(self.get_metainfo_filename())
+            type(self).metainfo_env = metainfo_env
+            self.parser_context.metainfo_env = metainfo_env
+        else:
+            self.parser_context.metainfo_env = type(self).metainfo_env
 
         # Initialize the backend. Use local backend if none given
         if backend is not None:
-            self.parser_context.super_backend = backend(metainfo_env)
+            self.parser_context.super_backend = backend(type(self).metainfo_env)
         else:
-            self.parser_context.super_backend = LocalBackend(metainfo_env)
+            self.parser_context.super_backend = LocalBackend(type(self).metainfo_env)
 
         # Check the list of default units
         default_unit_map = {}
@@ -90,7 +98,7 @@ class ParserInterface(object):
                 unit_conversion.ureg(unit)
 
                 # Check that the metaname is OK
-                meta = metainfo_env.infoKinds.get(metaname)
+                meta = ParserInterface.metainfo_env.infoKinds.get(metaname)
                 if meta is None:
                     raise KeyError("The metainfo name '{}' could not be found. Check for typos or try updating the metainfo repository.".format(metaname))