monitor becomes no-op when logger is not set

tensorpack/callbacks/saver.py

@@ -34,6 +34,7 @@ class ModelSaver(Triggerable):
         self.var_collections = var_collections
         if checkpoint_dir is None:
             checkpoint_dir = logger.LOG_DIR
+        assert os.path.isdir(checkpoint_dir), checkpoint_dir
         self.checkpoint_dir = checkpoint_dir
 
     def _setup_graph(self):

tensorpack/train/base.py

@@ -43,6 +43,7 @@ class Trainer(object):
 
         epoch_num (int): the number of epochs that have finished.
         local_step (int): the number of steps that have finished in the current epoch.
+        global_step (int): the number of steps that have finished.
     """
 
     def __init__(self, config):
@@ -59,10 +60,12 @@ class Trainer(object):
 
         self._callbacks = []
         self.register_callback(MaintainStepCounter())
-        for cb in self.config.callbacks:
+        for cb in config.callbacks:
             self.register_callback(cb)
 
-        self.monitors = config.monitors
+        self.monitors = []
+        for m in config.monitors:
+            self.register_monitor(m)
 
     def register_callback(self, cb):
         """
@@ -100,9 +103,6 @@ class Trainer(object):
         """
         Setup the trainer and be ready for the main loop.
         """
-        if not hasattr(logger, 'LOG_DIR'):
-            raise RuntimeError("logger directory wasn't set!")
-
         self._setup()   # subclass will setup the graph
 
         describe_model()

tensorpack/train/monitor.py

@@ -18,8 +18,16 @@ __all__ = ['TrainingMonitor', 'Monitors',
 
 
 class TrainingMonitor(object):
+    """
+    Monitor a training progress, by processing different types of
+    summary/statistics from trainer.
+    """
     def setup(self, trainer):
         self._trainer = trainer
+        self._setup()
+
+    def _setup(self):
+        pass
 
     def put_summary(self, summary):
         pass
@@ -34,6 +42,10 @@ class TrainingMonitor(object):
         pass
 
 
+class NoOpMonitor(TrainingMonitor):
+    pass
+
+
 class Monitors(TrainingMonitor):
     def __init__(self, monitors):
         # TODO filter by names
@@ -92,6 +104,13 @@ class Monitors(TrainingMonitor):
 
 
 class TFSummaryWriter(TrainingMonitor):
+    def __new__(cls):
+        if logger.LOG_DIR:
+            return super(TFSummaryWriter, cls).__new__(cls)
+        else:
+            logger.warn("logger directory was not set. Ignore TFSummaryWriter.")
+            return NoOpMonitor()
+
     def setup(self, trainer):
         super(TFSummaryWriter, self).setup(trainer)
         self._writer = tf.summary.FileWriter(logger.LOG_DIR, graph=tf.get_default_graph())
@@ -107,6 +126,13 @@ class TFSummaryWriter(TrainingMonitor):
 
 
 class JSONWriter(TrainingMonitor):
+    def __new__(cls):
+        if logger.LOG_DIR:
+            return super(JSONWriter, cls).__new__(cls)
+        else:
+            logger.warn("logger directory was not set. Ignore JSONWriter.")
+            return NoOpMonitor()
+
     def setup(self, trainer):
         super(JSONWriter, self).setup(trainer)
         self._dir = logger.LOG_DIR