Merge branch 'master' of https://github.com/PaddlePaddle/hapi into add-load-finetune

callbacks.py

+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# 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.
+
+import six
+import copy
+
+from progressbar import ProgressBar
+
+
+def config_callbacks(callbacks=None,
+                     model=None,
+                     batch_size=None,
+                     epochs=None,
+                     steps=None,
+                     log_freq=2,
+                     verbose=2,
+                     save_freq=1,
+                     metrics=None,
+                     mode='train'):
+    cbks = callbacks or []
+    cbks = cbks if isinstance(cbks, (list, tuple)) else [cbks]
+    if not any(isinstance(k, ProgBarLogger) for k in cbks) and verbose:
+        cbks = cbks + [ProgBarLogger(log_freq, verbose=verbose)]
+
+    if not any(isinstance(k, ModelCheckpoint) for k in cbks):
+        cbks = cbks + [ModelCheckpoint(save_freq)]
+
+    cbk_list = CallbackList(cbks)
+    cbk_list.set_model(model)
+    metrics = metrics or [] if mode != 'test' else []
+    params = {
+        'batch_size': batch_size,
+        'epochs': epochs,
+        'steps': steps,
+        'verbose': verbose,
+        'metrics': metrics,
+    }
+    cbk_list.set_params(params)
+    return cbk_list
+
+
+class CallbackList(object):
+    def __init__(self, callbacks=None):
+        # copy
+        self.callbacks = [c for c in callbacks]
+        self.params = {}
+        self.model = None
+
+    def append(self, callback):
+        self.callbacks.append(callback)
+
+    def __iter__(self):
+        return iter(self.callbacks)
+
+    def set_params(self, params):
+        for c in self.callbacks:
+            c.set_params(params)
+
+    def set_model(self, model):
+        for c in self.callbacks:
+            c.set_model(model)
+
+    def _call(self, name, *args):
+        for c in self.callbacks:
+            func = getattr(c, name)
+            func(*args)
+
+    def _check_mode(self, mode):
+        assert mode in ['train', 'eval', 'test'], \
+            'mode should be train, eval or test'
+
+    def on_begin(self, mode, logs=None):
+        self._check_mode(mode)
+        name = 'on_{}_begin'.format(mode)
+        self._call(name, logs)
+
+    def on_end(self, mode, logs=None):
+        self._check_mode(mode)
+        name = 'on_{}_end'.format(mode)
+        self._call(name, logs)
+
+    def on_epoch_begin(self, epoch=None, logs=None):
+        self._call('on_epoch_begin', epoch, logs)
+
+    def on_epoch_end(self, epoch=None, logs=None):
+        self._call('on_epoch_end', epoch, logs)
+
+    def on_batch_begin(self, mode, step=None, logs=None):
+        self._check_mode(mode)
+        name = 'on_{}_batch_begin'.format(mode)
+        self._call(name, step, logs)
+
+    def on_batch_end(self, mode, step=None, logs=None):
+        self._check_mode(mode)
+        name = 'on_{}_batch_end'.format(mode)
+        self._call(name, step, logs)
+
+
+class Callback(object):
+    def __init__(self):
+        self.model = None
+        self.params = {}
+
+    def set_params(self, params):
+        self.params = params
+
+    def set_model(self, model):
+        self.model = model
+
+    def on_train_begin(self, logs=None):
+        """
+        """
+
+    def on_train_end(self, logs=None):
+        """
+        """
+
+    def on_eval_begin(self, logs=None):
+        """
+        """
+
+    def on_eval_end(self, logs=None):
+        """
+        """
+
+    def on_test_begin(self, logs=None):
+        """
+        """
+
+    def on_test_end(self, logs=None):
+        """
+        """
+
+    def on_epoch_begin(self, epoch, logs=None):
+        """
+        """
+
+    def on_epoch_end(self, epoch, logs=None):
+        """
+        """
+
+    def on_train_batch_begin(self, step, logs=None):
+        """
+        """
+
+    def on_train_batch_end(self, step, logs=None):
+        """
+        """
+
+    def on_eval_batch_begin(self, step, logs=None):
+        """
+        """
+
+    def on_eval_batch_end(self, step, logs=None):
+        """
+        """
+
+    def on_eval_batch_begin(self, step, logs=None):
+        """
+        """
+
+    def on_eval_batch_end(self, step, logs=None):
+        """
+        """
+
+
+class ProgBarLogger(Callback):
+    def __init__(self, log_freq=1, verbose=2):
+        self.epochs = None
+        self.steps = None
+        self.progbar = None
+        self.verbose = verbose
+        self.log_freq = log_freq
+
+    def on_train_begin(self, logs=None):
+        self.epochs = self.params['epochs']
+        assert self.epochs
+        self.train_metrics = self.params['metrics']
+        assert self.train_metrics
+
+    def on_epoch_begin(self, epoch=None, logs=None):
+        self.steps = self.params['steps']
+        self.epoch = epoch
+        self.train_step = 0
+        if self.verbose and self.epochs:
+            print('Epoch %d/%d' % (epoch + 1, self.epochs))
+        self.train_progbar = ProgressBar(num=self.steps, verbose=self.verbose)
+
+    def _updates(self, logs, mode):
+        values = []
+        metrics = getattr(self, '%s_metrics' % (mode))
+        progbar = getattr(self, '%s_progbar' % (mode))
+        steps = getattr(self, '%s_step' % (mode))
+        for k in metrics:
+            if k in logs:
+                values.append((k, logs[k]))
+        progbar.update(steps, values)
+
+    def on_train_batch_end(self, step, logs=None):
+        logs = logs or {}
+        self.train_step = step
+
+        if self.train_step % self.log_freq == 0 and self.verbose:
+            # if steps is not None, last step will update in on_epoch_end
+            if self.steps and self.train_step < self.steps:
+                self._updates(logs, 'train')
+            else:
+                self._updates(logs, 'train')
+
+    def on_epoch_end(self, epoch, logs=None):
+        logs = logs or {}
+        if self.verbose:
+            self._updates(logs, 'train')
+
+    def on_eval_begin(self, logs=None):
+        self.eval_steps = logs.get('steps', None)
+        self.eval_metrics = logs.get('metrics_name', [])
+        self.eval_step = 0
+        self.evaled_samples = 0
+        self.eval_progbar = ProgressBar(
+            num=self.eval_steps, verbose=self.verbose)
+        print('Eval begin...')
+
+    def on_eval_batch_end(self, step, logs=None):
+        logs = logs or {}
+        self.eval_step = step
+        samples = logs.get('batch_size', 1)
+        self.evaled_samples += samples
+
+    def on_eval_end(self, logs=None):
+        logs = logs or {}
+        if self.verbose:
+            self._updates(logs, 'eval')
+            print('Eval samples: %d' % (self.evaled_samples))
+
+
+class ModelCheckpoint(Callback):
+    def __init__(self, save_freq=1, save_file='output'):
+        self.save_freq = save_freq
+        self.save_file = save_file
+
+    def on_epoch_begin(self, epoch=None, logs=None):
+        self.epoch = epoch
+
+    def on_epoch_end(self, epoch, logs=None):
+        if self.model and self.epoch % self.save_freq == 0:
+            path = '{}/{}'.format(self.save_file, epoch)
+            print('save checkpoint at {}'.format(path))
+            self.model.save(path)
+
+    def on_train_end(self, logs=None):
+        if self.model:
+            path = '{}/final'.format(self.save_file)
+            print('save checkpoint at {}'.format(path))
+            self.model.save(path)

metrics.py

@@ -44,21 +44,33 @@ class Metric(object):
         """
         Reset states and result
         """
-        raise NotImplementedError("function 'reset' not implemented in {}.".format(self.__class__.__name__))
+        raise NotImplementedError("function 'reset' not implemented in {}.".
+                                  format(self.__class__.__name__))
 
     @abc.abstractmethod
     def update(self, *args, **kwargs):
         """
         Update states for metric
         """
-        raise NotImplementedError("function 'update' not implemented in {}.".format(self.__class__.__name__))
+        raise NotImplementedError("function 'update' not implemented in {}.".
+                                  format(self.__class__.__name__))
 
     @abc.abstractmethod
     def accumulate(self):
         """
         Accumulates statistics, computes and returns the metric value
         """
-        raise NotImplementedError("function 'accumulate' not implemented in {}.".format(self.__class__.__name__))
+        raise NotImplementedError(
+            "function 'accumulate' not implemented in {}.".format(
+                self.__class__.__name__))
+
+    @abc.abstractmethod
+    def name(self):
+        """
+        Returns metric name
+        """
+        raise NotImplementedError("function 'name' not implemented in {}.".
+                                  format(self.__class__.__name__))
 
     def add_metric_op(self, pred, label):
         """
@@ -72,11 +84,12 @@ class Accuracy(Metric):
     Encapsulates accuracy metric logic
     """
 
-    def __init__(self, topk=(1, ), *args, **kwargs):
-       super(Accuracy, self).__init__(*args, **kwargs) 
-       self.topk = topk
-       self.maxk = max(topk)
-       self.reset()
+    def __init__(self, topk=(1, ), name=None, *args, **kwargs):
+        super(Accuracy, self).__init__(*args, **kwargs)
+        self.topk = topk
+        self.maxk = max(topk)
+        self._init_name(name)
+        self.reset()
 
     def add_metric_op(self, pred, label, *args, **kwargs):
         pred = fluid.layers.argsort(pred[0], descending=True)[1][:, :self.maxk]
@@ -103,3 +116,12 @@ class Accuracy(Metric):
             res.append(float(t) / c)
         return res
 
+    def _init_name(self, name):
+        name = name or 'acc'
+        if self.maxk != 1:
+            self._name = ['{}_top{}'.format(name, k) for k in self.topk]
+        else:
+            self._name = ['acc']
+
+    def name(self):
+        return self._name

model.py

@@ -18,16 +18,18 @@ import inspect
 import os
 import pickle
 import six
-from collections import OrderedDict
-
 import numpy as np
+from collections import Iterable
+from collections import OrderedDict
 
 from paddle import fluid
 from paddle.fluid.framework import in_dygraph_mode, Variable
 from paddle.fluid.executor import global_scope
 from paddle.fluid.io import is_belong_to_optimizer
 from paddle.fluid.dygraph.base import to_variable
+
 from metrics import Metric
+from callbacks import config_callbacks
 
 __all__ = ['Model', 'Loss', 'CrossEntropy', 'Input']
 
@@ -612,7 +614,6 @@ class Model(fluid.dygraph.Layer):
         self._labels = None
         self._loss_function = None
         self._loss_weights = None
-        self._loss = None
         self._optimizer = None
         self._device = None
         self._device_ids = None
@@ -708,6 +709,9 @@ class Model(fluid.dygraph.Layer):
                         param_type.__name__)
         return self._adapter.load(path, reset_optimizer, list(load_param_vars))
 
+    def parameters(self, *args, **kwargs):
+        return self._adapter.parameters(*args, **kwargs)
+
     def prepare(self,
                 optimizer=None,
                 loss_function=None,
@@ -778,5 +782,102 @@ class Model(fluid.dygraph.Layer):
         if not in_dygraph_mode():
             self._adapter.prepare()
 
-    def parameters(self, *args, **kwargs):
-        return self._adapter.parameters(*args, **kwargs)
+    def fit(
+            self,
+            train_loader=None,
+            eval_loader=None,
+            epochs=1,
+            eval_freq=1,
+            log_freq=10,
+            save_freq=1,
+            verbose=2,
+            callbacks=None, ):
+        """
+        FIXME: add more comments and usage
+        Args:
+            train_loader (DataLoader): an iterable data loader is used for train.
+            eval_loader (DataLoader): an iterable data loader is used for
+                evaluation at the end of epoch. If None, will not do evaluation.
+            epochs (int): number of epochs to train the model.
+            eval_freq (int): evaluation frequency in epoch.
+            log_freq (int): frequency to print log during training.
+            save_freq (int): frequency to save checkpoint during training.
+            verbose (int): verbosity mode, should be 0, 1, or 2.
+                0 = silent, 1 = progress bar, 2 = one line per epoch.
+            callbacks (Callback|None): list of `Callback` instances to apply
+                during training.
+        """
+        do_eval = eval_loader is not None
+        metrics_name = self._metrics_name()
+        cbks = config_callbacks(
+            callbacks,
+            model=self,
+            epochs=epochs,
+            steps=None,
+            log_freq=log_freq,
+            save_freq=save_freq,
+            verbose=verbose,
+            metrics=self._metrics_name(), )
+
+        def _run_one_epoch(data_loader, callbacks, mode):
+            size = data_loader.size if hasattr(data_loader, 'size') else None
+            logs = {
+                'steps': size,
+                'metrics_name': metrics_name,
+            }
+            for step, data in enumerate(data_loader):
+                cbks.on_batch_begin(mode, step, logs)
+                if mode == 'train':
+                    outs = self.train(*data)
+                else:
+                    outs = self.eval(*data)
+
+                # losses
+                loss = outs[0] if self._metrics else outs
+                metrics = [[l[0] for l in loss]]
+
+                # metrics
+                for metric in self._metrics:
+                    res = metric.accumulate()
+                    metrics.extend(to_list(res))
+                assert len(metrics_name) == len(metrics)
+                for k, v in zip(metrics_name, metrics):
+                    logs[k] = v
+
+                logs['step'] = step
+                logs['batch_size'] = data[0].shape[0]
+
+                cbks.on_batch_end(mode, step, logs)
+            self._reset_metrics()
+            return logs
+
+        cbks.on_begin('train')
+        for epoch in range(epochs):
+            cbks.on_epoch_begin(epoch)
+            # FIXME: adapt to DataLoader
+            loader = train_loader
+            if not isinstance(train_loader, Iterable):
+                loader = train_loader()
+            logs = _run_one_epoch(loader, cbks, 'train')
+            cbks.on_epoch_end(epoch, logs)
+
+            if do_eval and epoch % eval_freq == 0:
+                cbks.on_begin('eval', logs)
+                # FIXME: adapt to DataLoader
+                loader = eval_loader
+                if not isinstance(eval_loader, Iterable):
+                    loader = eval_loader()
+                logs = _run_one_epoch(eval_loader(), cbks, 'eval')
+                cbks.on_end('eval', logs)
+
+        cbks.on_end('train', logs)
+
+    def _reset_metrics(self):
+        for metric in self._metrics:
+            metric.reset()
+
+    def _metrics_name(self):
+        metrics_name = ['loss']
+        for m in self._metrics:
+            metrics_name.extend(to_list(m.name()))
+        return metrics_name

progressbar.py

+import sys
+import time
+import numpy as np
+
+
+class ProgressBar(object):
+    """progress bar """
+
+    def __init__(self,
+                 num=None,
+                 width=30,
+                 verbose=1,
+                 start=True,
+                 file=sys.stdout):
+        self._num = num
+        if isinstance(num, int) and num <= 0:
+            raise TypeError('num should be None or integer (> 0)')
+        max_width = self._get_max_width()
+        self._width = width if width <= max_width else max_width
+        self._total_width = 0
+        self._verbose = verbose
+        self.file = file
+        self._values = {}
+        self._values_order = []
+        if start:
+            self._start = time.time()
+        self._last_update = 0
+
+        self._dynamic_display = (
+            (hasattr(self.file, 'isatty') and
+             self.file.isatty()) or 'ipykernel' in sys.modules or
+            'posix' in sys.modules or 'PYCHARM_HOSTED' in os.environ)
+
+    def _get_max_width(self):
+        if sys.version_info > (3, 3):
+            from shutil import get_terminal_size
+        else:
+            from backports.shutil_get_terminal_size import get_terminal_size
+        terminal_width, _ = get_terminal_size()
+        max_width = min(int(terminal_width * 0.6), terminal_width - 50)
+        return max_width
+
+    def start(self):
+        self.file.flush()
+        self._start = time.time()
+
+    def update(self, current_num, values=None):
+        now = time.time()
+
+        if current_num:
+            time_per_unit = (now - self._start) / current_num
+        else:
+            time_per_unit = 0
+
+        if time_per_unit >= 1 or time_per_unit == 0:
+            fps = ' - %.0fs/%s' % (time_per_unit, 'step')
+        elif time_per_unit >= 1e-3:
+            fps = ' - %.0fms/%s' % (time_per_unit * 1e3, 'step')
+        else:
+            fps = ' - %.0fus/%s' % (time_per_unit * 1e6, 'step')
+
+        info = ''
+        if self._verbose == 1:
+            prev_total_width = self._total_width
+
+            if self._dynamic_display:
+                sys.stdout.write('\b' * prev_total_width)
+                sys.stdout.write('\r')
+            else:
+                sys.stdout.write('\n')
+
+            if self._num is not None:
+                numdigits = int(np.log10(self._num)) + 1
+
+                bar_chars = ('step %' + str(numdigits) + 'd/%d [') % (
+                    current_num, self._num)
+                prog = float(current_num) / self._num
+                prog_width = int(self._width * prog)
+
+                if prog_width > 0:
+                    bar_chars += ('=' * (prog_width - 1))
+                    if current_num < self._num:
+                        bar_chars += '>'
+                    else:
+                        bar_chars += '='
+                bar_chars += ('.' * (self._width - prog_width))
+                bar_chars += ']'
+            else:
+                bar_chars = 'step %3d' % current_num
+
+            self._total_width = len(bar_chars)
+            sys.stdout.write(bar_chars)
+
+            for k, val in values:
+                info += ' - %s:' % k
+                val = val if isinstance(val, list) else [val]
+                for i, v in enumerate(val):
+                    if isinstance(v, (float, np.float32, np.float64)):
+                        if abs(v) > 1e-3:
+                            info += ' %.4f' % v
+                        else:
+                            info += ' %.4e' % v
+                    else:
+                        info += ' %s' % v
+
+            if self._num is not None and current_num < self._num:
+                eta = time_per_unit * (self._num - current_num)
+                if eta > 3600:
+                    eta_format = '%d:%02d:%02d' % (eta // 3600, (eta % 3600) //
+                                                   60, eta % 60)
+                elif eta > 60:
+                    eta_format = '%d:%02d' % (eta // 60, eta % 60)
+                else:
+                    eta_format = '%ds' % eta
+
+                info += ' - ETA: %s' % eta_format
+
+            info += fps
+            self._total_width += len(info)
+            if prev_total_width > self._total_width:
+                info += (' ' * (prev_total_width - self._total_width))
+
+            # newline for another epoch
+            if self._num is not None and current_num >= self._num:
+                info += '\n'
+            if self._num is None:
+                info += '\n'
+
+            sys.stdout.write(info)
+            sys.stdout.flush()
+            self._last_update = now
+        elif self._verbose == 2:
+            if self._num:
+                numdigits = int(np.log10(self._num)) + 1
+                count = ('step %' + str(numdigits) + 'd/%d') % (current_num,
+                                                                self._num)
+            else:
+                count = 'step %3d' % current_num
+            info = count + info
+
+            for k, val in values:
+                info += ' - %s:' % k
+                val = val if isinstance(val, list) else [val]
+                for v in val:
+                    if isinstance(v, (float, np.float32, np.float64)):
+                        if abs(v) > 1e-3:
+                            info += ' %.4f' % v
+                        else:
+                            info += ' %.4e' % v
+                    elif isinstance(v, np.ndarray) and \
+                         isinstance(v.size, 1) and \
+                         isinstance(v.dtype, (np.float32, np.float64)):
+                        if abs(v[0]) > 1e-3:
+                            info += ' %.4f' % v[0]
+                        else:
+                            info += ' %.4e' % v[0]
+                    else:
+                        info += ' %s' % v
+
+            info += fps
+            info += '\n'
+            sys.stdout.write(info)
+            sys.stdout.flush()

tests/test_callbacks.py

+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# 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.
+
+import unittest
+import time
+import random
+
+from callbacks import config_callbacks
+
+
+class TestCallbacks(unittest.TestCase):
+    def test_callback(self):
+        epochs = 2
+        steps = 50
+        freq = 1
+        eval_steps = 20
+        cbks = config_callbacks(
+            batch_size=128,
+            epochs=epochs,
+            steps=steps,
+            verbose=2,
+            metrics=['loss', 'acc'], )
+        cbks.on_begin('train')
+
+        logs = {'loss': 50.341673, 'acc': 0.00256}
+        for epoch in range(epochs):
+            cbks.on_epoch_begin(epoch)
+            for step in range(steps):
+                cbks.on_batch_begin('train', step, logs)
+                logs['loss'] -= random.random() * 0.1
+                logs['acc'] += random.random() * 0.1
+                time.sleep(0.005)
+                cbks.on_batch_end('train', step, logs)
+            cbks.on_epoch_end(epoch, logs)
+
+            eval_logs = {'eval_loss': 20.341673, 'eval_acc': 0.256}
+            params = {
+                'eval_steps': eval_steps,
+                'eval_metrics': ['eval_loss', 'eval_acc'],
+                'log_freq': 10,
+            }
+            cbks.on_begin('eval', params)
+            for step in range(eval_steps):
+                cbks.on_batch_begin('eval', step, logs)
+                eval_logs['eval_loss'] -= random.random() * 0.1
+                eval_logs['eval_acc'] += random.random() * 0.1
+                eval_logs['batch_size'] = 2
+                time.sleep(0.005)
+                cbks.on_batch_end('eval', step, eval_logs)
+            cbks.on_end('eval', eval_logs)
+
+        cbks.on_end('train')
+
+
+if __name__ == '__main__':
+    unittest.main()

tests/test_model.py

+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# 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 __future__ import division
+from __future__ import print_function
+
+import unittest
+
+import os
+import numpy as np
+import contextlib
+
+import paddle
+from paddle import fluid
+from paddle.fluid.dygraph.nn import Conv2D, Pool2D, Linear
+from model import Model, CrossEntropy, Input, Loss
+from metrics import Accuracy
+from callbacks import ProgBarLogger
+
+
+class SimpleImgConvPool(fluid.dygraph.Layer):
+    def __init__(self,
+                 num_channels,
+                 num_filters,
+                 filter_size,
+                 pool_size,
+                 pool_stride,
+                 pool_padding=0,
+                 pool_type='max',
+                 global_pooling=False,
+                 conv_stride=1,
+                 conv_padding=0,
+                 conv_dilation=1,
+                 conv_groups=None,
+                 act=None,
+                 use_cudnn=False,
+                 param_attr=None,
+                 bias_attr=None):
+        super(SimpleImgConvPool, self).__init__('SimpleConv')
+
+        self._conv2d = Conv2D(
+            num_channels=num_channels,
+            num_filters=num_filters,
+            filter_size=filter_size,
+            stride=conv_stride,
+            padding=conv_padding,
+            dilation=conv_dilation,
+            groups=conv_groups,
+            param_attr=None,
+            bias_attr=None,
+            use_cudnn=use_cudnn)
+
+        self._pool2d = Pool2D(
+            pool_size=pool_size,
+            pool_type=pool_type,
+            pool_stride=pool_stride,
+            pool_padding=pool_padding,
+            global_pooling=global_pooling,
+            use_cudnn=use_cudnn)
+
+    def forward(self, inputs):
+        x = self._conv2d(inputs)
+        x = self._pool2d(x)
+        return x
+
+
+class MNIST(Model):
+    def __init__(self):
+        super(MNIST, self).__init__()
+        self._simple_img_conv_pool_1 = SimpleImgConvPool(
+            1, 20, 5, 2, 2, act="relu")
+
+        self._simple_img_conv_pool_2 = SimpleImgConvPool(
+            20, 50, 5, 2, 2, act="relu")
+
+        pool_2_shape = 50 * 4 * 4
+        SIZE = 10
+        scale = (2.0 / (pool_2_shape**2 * SIZE))**0.5
+        self._fc = Linear(
+            800,
+            10,
+            param_attr=fluid.param_attr.ParamAttr(
+                initializer=fluid.initializer.NormalInitializer(
+                    loc=0.0, scale=scale)),
+            act="softmax")
+
+    def forward(self, inputs):
+        x = self._simple_img_conv_pool_1(inputs)
+        x = self._simple_img_conv_pool_2(x)
+        x = fluid.layers.flatten(x, axis=1)
+        x = self._fc(x)
+        return x
+
+
+@contextlib.contextmanager
+def null_guard():
+    yield
+
+
+class MLP(Model):
+    def __init__(self):
+        super(MLP, self).__init__()
+        SIZE = 10
+        self._fc1 = Linear(784, 200, act="relu")
+        self._fc2 = Linear(200, 200, act="relu")
+        self._fc3 = Linear(200, 200, act="relu")
+        self._fc4 = Linear(200, 10, act="softmax")
+        self._fc5 = Linear(200, 10, act="softmax")
+
+    def forward(self, inputs):
+        x1 = self._fc1(inputs)
+        x2 = self._fc2(x1)
+        x3 = self._fc3(x2)
+        o1 = self._fc5(x3)
+        o2 = self._fc4(x2)
+        return o1, o2
+
+
+class MyCrossEntropy(Loss):
+    def __init__(self, average=True):
+        super(MyCrossEntropy, self).__init__()
+
+    def forward(self, outputs, labels):
+        loss1 = fluid.layers.cross_entropy(outputs[0], labels[0])
+        loss2 = fluid.layers.cross_entropy(outputs[1], labels[0])
+        return [loss1, loss2]
+
+
+class TestModel(unittest.TestCase):
+    def fit(self, dynamic, is_mlp=False):
+        im_shape = (-1, 784) if is_mlp else (-1, 1, 28, 28)
+        guard = fluid.dygraph.guard() if dynamic else null_guard()
+        batch_size = 128
+        train_loader = fluid.io.xmap_readers(
+            lambda b: [np.array([x[0] for x in b]).reshape(im_shape),
+                       np.array([x[1] for x in b]).reshape(-1, 1)],
+            paddle.batch(fluid.io.shuffle(paddle.dataset.mnist.train(), 6e4),
+                         batch_size=batch_size, drop_last=True), 1, 1)
+        val_loader = fluid.io.xmap_readers(
+            lambda b: [np.array([x[0] for x in b]).reshape(im_shape),
+                       np.array([x[1] for x in b]).reshape(-1, 1)],
+            paddle.batch(paddle.dataset.mnist.test(),
+                         batch_size=batch_size, drop_last=False), 1, 1)
+        with guard:
+            inputs = [Input(im_shape, 'float32', name='image')]
+            labels = [Input([None, 1], 'int64', name='label')]
+            model = MNIST() if not is_mlp else MLP()
+            optim = fluid.optimizer.Momentum(
+                learning_rate=0.01,
+                momentum=.9,
+                parameter_list=model.parameters())
+            loss = CrossEntropy() if not is_mlp else MyCrossEntropy()
+            model.prepare(optim, loss, Accuracy(), inputs, labels)
+            cbk = ProgBarLogger(50)
+            model.fit(train_loader, val_loader, epochs=2, callbacks=cbk)
+
+    def test_fit_static(self):
+        self.fit(False)
+
+    def test_fit_dygraph(self):
+        self.fit(True)
+
+    def test_fit_static_multi_loss(self):
+        self.fit(False, MyCrossEntropy())
+
+    def test_fit_dygraph_multi_loss(self):
+        self.fit(True, MyCrossEntropy())
+
+
+if __name__ == '__main__':
+    unittest.main()

tests/test_progressbar.py

+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# 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.
+
+import unittest
+import random
+import time
+
+from progressbar import ProgressBar
+
+
+class TestProgressBar(unittest.TestCase):
+    def prog_bar(self, num, epoch, width, verbose=1):
+        for epoch in range(epoch):
+            progbar = ProgressBar(num, verbose=verbose)
+            values = [
+                ['loss', 50.341673],
+                ['acc', 0.00256],
+            ]
+            for step in range(1, num + 1):
+                values[0][1] -= random.random() * 0.1
+                values[1][1] += random.random() * 0.1
+                if step % 10 == 0:
+                    progbar.update(step, values)
+                time.sleep(0.002)
+            progbar.update(step, values)
+
+    def test1(self):
+        self.prog_bar(50, 1, 30)
+
+    def test2(self):
+        self.prog_bar(50, 2, 30)
+
+    def test4(self):
+        self.prog_bar(50, 2, 30, verbose=2)
+
+
+if __name__ == '__main__':
+    unittest.main()