baselines: default logger similar to configure() logger, rcall: don't call logger.configure() for new rl_algs

* error if logger looks wrong

* check version of logger, call logger.configure() on import

* remove changes entry

* add version to rl-algs

* fix typo

* add comment

* switch version to string

* set logger env variable

baselines/logger.py

@@ -344,8 +344,6 @@ class Logger(object):
             if isinstance(fmt, SeqWriter):
                 fmt.writeseq(map(str, args))
 
-Logger.DEFAULT = Logger.CURRENT = Logger(dir=None, output_formats=[HumanOutputFormat(sys.stdout)])
-
 def configure(dir=None, format_strs=None):
     if dir is None:
         dir = os.getenv('OPENAI_LOGDIR')
@@ -356,8 +354,12 @@ def configure(dir=None, format_strs=None):
     os.makedirs(dir, exist_ok=True)
 
     log_suffix = ''
-    from mpi4py import MPI
-    rank = MPI.COMM_WORLD.Get_rank()
+    rank = 0
+    # check environment variables here instead of importing mpi4py
+    # to avoid calling MPI_Init() when this module is imported
+    for varname in ['PMI_RANK', 'OMPI_COMM_WORLD_RANK']:
+        if varname in os.environ:
+            rank = int(os.environ[varname])
     if rank > 0:
         log_suffix = "-rank%03i" % rank
 
@@ -372,6 +374,14 @@ def configure(dir=None, format_strs=None):
     Logger.CURRENT = Logger(dir=dir, output_formats=output_formats)
     log('Logging to %s'%dir)
 
+def _configure_default_logger():
+    format_strs = None
+    # keep the old default of only writing to stdout
+    if 'OPENAI_LOG_FORMAT' not in os.environ:
+        format_strs = ['stdout']
+    configure(format_strs=format_strs)
+    Logger.DEFAULT = Logger.CURRENT
+
 def reset():
     if Logger.CURRENT is not Logger.DEFAULT:
         Logger.CURRENT.close()
@@ -471,5 +481,8 @@ def read_tb(path):
             data[step-1, colidx] = value
     return pandas.DataFrame(data, columns=tags)
 
+# configure the default logger on import
+_configure_default_logger()
+
 if __name__ == "__main__":
     _demo()