[LNT] Python 3 support: adapt to removal of execfile

[thopre]

Summary

Replace calls to execfile by calling exec on the result of calling
compile on the result of calling open().read().

[thopre]

Ping?

[hubert.reinterpretcast]

LGTM.

lnt/server/db/migrate.py

def update_schema(engine, versions, available_migrations, schema_name):
 
     logger.info("updating schema %r from version %r to current version %r",
                 schema_name, db_version, current_version)
     while db_version < current_version:
         # Lookup the upgrade function for this version.
         upgrade_script = schema_migrations[db_version]
 
         globals = {}
-        execfile(upgrade_script, globals)
+        exec(compile(open(upgrade_script).read(), upgrade_script, 'exec'),
+             globals)
         upgrade_method = globals['upgrade']
 
         # Execute the upgrade.
         #
         # FIXME: Backup the database here.
         #
         # FIXME: Execute this inside a transaction?
         logger.info("applying upgrade for version %d to %d" % (

lnt/server/db/rules_manager.py

 
 def register_hooks():
     """Exec all the rules files.  Gather the hooks from them
     and load them into the hook dict for later use.
     """
     global HOOKS_LOADED
     for name, path in list(load_rules().items()):
         globals = {}
-        execfile(path, globals)
+        exec(compile(open(path).read(), path, 'exec'), globals)
         DESCRIPTIONS[name] = globals['__doc__']
         for hook_name in list(HOOKS.keys()):
             if hook_name in globals:
                 HOOKS[hook_name].append(globals[hook_name])
     HOOKS_LOADED = True
     return HOOKS