add logger

hapi/__init__.py

@@ -11,7 +11,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-
+from hapi import logger
 from hapi.configure import Config
 from hapi import callbacks
 from hapi import datasets
@@ -22,16 +22,11 @@ from hapi import model
 from hapi import progressbar
 from hapi import text
 from hapi import vision
+from hapi import loss
+
+logger.setup_logger()
 
 __all__ = [
-    'Config',
-    'callbacks',
-    'datasets',
-    'distributed',
-    'download',
-    'metrics',
-    'model',
-    'progressbar',
-    'text',
-    'vision',
+    'Config', 'callbacks', 'datasets', 'distributed', 'download', 'metrics',
+    'model', 'progressbar', 'text', 'vision', 'loss'
 ]

hapi/logger.py

+import os
+import sys
+import logging
+import functools
+
+from paddle.fluid.dygraph.parallel import ParallelEnv
+
+
+@functools.lru_cache()
+def setup_logger(output=None, name="hapi", log_level=logging.INFO):
+    """
+    Initialize logger of hapi and set its verbosity level to "INFO".
+
+    Args:
+        output (str): a file name or a directory to save log. If None, will not save log file.
+            If ends with ".txt" or ".log", assumed to be a file name.
+            Otherwise, logs will be saved to `output/log.txt`.
+        name (str): the root module name of this logger. Default: 'hapi'
+
+    Returns:
+        logging.Logger: a logger
+    """
+    logger = logging.getLogger(name)
+    logger.propagate = False
+
+    format_str = '%(asctime)s - %(name)s - %(levelname)s - %(message)s'
+    logging.basicConfig(format=format_str, level=log_level)
+
+    # stdout logging: only local rank==0
+    local_rank = ParallelEnv().local_rank
+    if local_rank == 0:
+        ch = logging.StreamHandler(stream=sys.stdout)
+        ch.setLevel(logging.DEBUG)
+
+        ch.setFormatter(logging.Formatter(format_str))
+        logger.addHandler(ch)
+
+    # file logging if output is not None: all workers
+    if output is not None:
+        if output.endswith(".txt") or output.endswith(".log"):
+            filename = output
+        else:
+            filename = os.path.join(output, "log.txt")
+        if local_rank > 0:
+            filename = filename + ".rank{}".format(local_rank)
+
+        if not os.path.exists(os.path.dirname(filename)):
+            os.makedirs(os.path.dirname(filename))
+
+        fh = logging.StreamHandler(filename)
+        fh.setLevel(logging.DEBUG)
+        fh.setFormatter(logging.Formatter(format_str))
+        logger.addHandler(fh)
+
+    return logger