tensorflow_privacy/privacy/bolton/optimizer_test.py
Christopher Choquette Choo ec18db5ec5 Working bolton model without unit tests.
-- moving to Bolton Optimizer
Model is now just a convenient wrapper and example for users.
Optimizer holds ALL Bolton privacy requirements.
Optimizer is used as a context manager, and must be passed the model's layers.
Unit tests incomplete, committing for visibility into the design.
2019-06-13 01:01:31 -04:00

344 lines
10 KiB
Python

# Copyright 2018, The TensorFlow Authors.
#
# 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.
"""Unit testing for optimizer.py"""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import tensorflow as tf
from tensorflow.python.platform import test
from tensorflow.python.keras.optimizer_v2.optimizer_v2 import OptimizerV2
from tensorflow.python.keras import keras_parameterized
from tensorflow.python.keras.regularizers import L1L2
from tensorflow.python.keras import losses
from tensorflow.python.keras.models import Model
from tensorflow.python.framework import ops as _ops
from tensorflow.python.framework import test_util
from absl.testing import parameterized
from privacy.bolton.loss import StrongConvexMixin
from privacy.bolton import optimizer as opt
class TestModel(Model):
"""
Bolton episilon-delta model
Uses 4 key steps to achieve privacy guarantees:
1. Adds noise to weights after training (output perturbation).
2. Projects weights to R after each batch
3. Limits learning rate
4. Use a strongly convex loss function (see compile)
For more details on the strong convexity requirements, see:
Bolt-on Differential Privacy for Scalable Stochastic Gradient
Descent-based Analytics by Xi Wu et. al.
"""
def __init__(self, n_classes=2):
"""
Args:
n_classes: number of output classes to predict.
epsilon: level of privacy guarantee
noise_distribution: distribution to pull weight perturbations from
weights_initializer: initializer for weights
seed: random seed to use
dtype: data type to use for tensors
"""
super(TestModel, self).__init__(name='bolton', dynamic=False)
self.n_classes = n_classes
self.layer_input_shape = (16, 1)
self.output_layer = tf.keras.layers.Dense(
self.n_classes,
input_shape=self.layer_input_shape,
kernel_regularizer=L1L2(l2=1),
kernel_initializer='glorot_uniform',
)
# def call(self, inputs):
# """Forward pass of network
#
# Args:
# inputs: inputs to neural network
#
# Returns:
#
# """
# return self.output_layer(inputs)
class TestLoss(losses.Loss, StrongConvexMixin):
"""Test loss function for testing Bolton model"""
def __init__(self, reg_lambda, C, radius_constant, name='test'):
super(TestLoss, self).__init__(name=name)
self.reg_lambda = reg_lambda
self.C = C
self.radius_constant = radius_constant
def radius(self):
"""Radius of R-Ball (value to normalize weights to after each batch)
Returns: radius
"""
return _ops.convert_to_tensor_v2(1, dtype=tf.float32)
def gamma(self):
""" Gamma strongly convex
Returns: gamma
"""
return _ops.convert_to_tensor_v2(1, dtype=tf.float32)
def beta(self, class_weight):
"""Beta smoothess
Args:
class_weight: the class weights used.
Returns: Beta
"""
return _ops.convert_to_tensor_v2(1, dtype=tf.float32)
def lipchitz_constant(self, class_weight):
""" L lipchitz continuous
Args:
class_weight: class weights used
Returns: L
"""
return _ops.convert_to_tensor_v2(1, dtype=tf.float32)
def call(self, val0, val1):
"""Loss function that is minimized at the mean of the input points."""
return 0.5 * tf.reduce_sum(tf.math.squared_difference(val0, val1), axis=1)
def max_class_weight(self, class_weight):
if class_weight is None:
return 1
def kernel_regularizer(self):
return L1L2(l2=self.reg_lambda)
class TestOptimizer(OptimizerV2):
"""Optimizer used for testing the Bolton optimizer"""
def __init__(self):
super(TestOptimizer, self).__init__('test')
self.not_private = 'test'
self.iterations = tf.constant(1, dtype=tf.float32)
self._iterations = tf.constant(1, dtype=tf.float32)
def _compute_gradients(self, loss, var_list, grad_loss=None):
return 'test'
def get_config(self):
return 'test'
def from_config(self, config, custom_objects=None):
return 'test'
def _create_slots(self):
return 'test'
def _resource_apply_dense(self, grad, handle):
return 'test'
def _resource_apply_sparse(self, grad, handle, indices):
return 'test'
def get_updates(self, loss, params):
return 'test'
def apply_gradients(self, grads_and_vars, name=None):
return 'test'
def minimize(self, loss, var_list, grad_loss=None, name=None):
return 'test'
def get_gradients(self, loss, params):
return 'test'
def limit_learning_rate(self):
return 'test'
class BoltonOptimizerTest(keras_parameterized.TestCase):
"""Bolton Optimizer tests"""
@test_util.run_all_in_graph_and_eager_modes
@parameterized.named_parameters([
{'testcase_name': 'branch beta',
'fn': 'limit_learning_rate',
'args': [tf.Variable(2, dtype=tf.float32),
tf.Variable(1, dtype=tf.float32)],
'result': tf.Variable(0.5, dtype=tf.float32),
'test_attr': 'learning_rate'},
{'testcase_name': 'branch gamma',
'fn': 'limit_learning_rate',
'args': [tf.Variable(1, dtype=tf.float32),
tf.Variable(1, dtype=tf.float32)],
'result': tf.Variable(1, dtype=tf.float32),
'test_attr': 'learning_rate'},
{'testcase_name': 'getattr',
'fn': '__getattr__',
'args': ['dtype'],
'result': tf.float32,
'test_attr': None},
{'testcase_name': 'project_weights_to_r',
'fn': 'project_weights_to_r',
'args': ['dtype'],
'result': tf.float32,
'test_attr': None},
])
def test_fn(self, fn, args, result, test_attr):
"""test that a fn of Bolton optimizer is working as expected.
Args:
fn: method of Optimizer to test
args: args to optimizer fn
result: the expected result
test_attr: None if the fn returns the test result. Otherwise, this is
the attribute of Bolton to check against result with.
"""
tf.random.set_seed(1)
loss = TestLoss(1, 1, 1)
private = opt.Bolton(TestOptimizer(), loss)
res = getattr(private, fn, None)(*args)
if test_attr is not None:
res = getattr(private, test_attr, None)
if hasattr(res, 'numpy') and hasattr(result, 'numpy'): # both tensors/not
res = res.numpy()
result = result.numpy()
self.assertEqual(res, result)
@parameterized.named_parameters([
{'testcase_name': 'fn: get_updates',
'fn': 'get_updates',
'args': [0, 0]},
{'testcase_name': 'fn: get_config',
'fn': 'get_config',
'args': []},
{'testcase_name': 'fn: from_config',
'fn': 'from_config',
'args': [0]},
{'testcase_name': 'fn: _resource_apply_dense',
'fn': '_resource_apply_dense',
'args': [1, 1]},
{'testcase_name': 'fn: _resource_apply_sparse',
'fn': '_resource_apply_sparse',
'args': [1, 1, 1]},
{'testcase_name': 'fn: apply_gradients',
'fn': 'apply_gradients',
'args': [1]},
{'testcase_name': 'fn: minimize',
'fn': 'minimize',
'args': [1, 1]},
{'testcase_name': 'fn: _compute_gradients',
'fn': '_compute_gradients',
'args': [1, 1]},
{'testcase_name': 'fn: get_gradients',
'fn': 'get_gradients',
'args': [1, 1]},
])
def test_rerouted_function(self, fn, args):
""" tests that a method of the internal optimizer is correctly routed from
the Bolton instance to the internal optimizer instance (TestOptimizer,
here).
Args:
fn: fn to test
args: arguments to that fn
"""
loss = TestLoss(1, 1, 1)
optimizer = TestOptimizer()
optimizer = opt.Bolton(optimizer, loss)
model = TestModel(2)
model.compile(optimizer, loss)
model.layers[0].kernel_initializer(model.layer_input_shape)
print(model.layers[0].__dict__)
with optimizer('laplace', 2, model.layers, 1, 1, model.n_classes):
self.assertEqual(
getattr(optimizer, fn, lambda: 'fn not found')(*args),
'test'
)
@parameterized.named_parameters([
{'testcase_name': 'fn: limit_learning_rate',
'fn': 'limit_learning_rate',
'args': [1, 1, 1]},
{'testcase_name': 'fn: project_weights_to_r',
'fn': 'project_weights_to_r',
'args': []},
{'testcase_name': 'fn: get_noise',
'fn': 'get_noise',
'args': [1, 1, 1, 1]},
])
def test_not_reroute_fn(self, fn, args):
"""Test that a fn that should not be rerouted to the internal optimizer is
in face not rerouted.
Args:
fn: fn to test
args: arguments to that fn
"""
optimizer = TestOptimizer()
loss = TestLoss(1, 1, 1)
optimizer = opt.Bolton(optimizer, loss)
self.assertNotEqual(getattr(optimizer, fn, lambda: 'test')(*args),
'test')
@parameterized.named_parameters([
{'testcase_name': 'attr: _iterations',
'attr': '_iterations'}
])
def test_reroute_attr(self, attr):
""" test that attribute of internal optimizer is correctly rerouted to
the internal optimizer
Args:
attr: attribute to test
result: result after checking attribute
"""
loss = TestLoss(1, 1, 1)
internal_optimizer = TestOptimizer()
optimizer = opt.Bolton(internal_optimizer, loss)
self.assertEqual(getattr(optimizer, attr),
getattr(internal_optimizer, attr)
)
@parameterized.named_parameters([
{'testcase_name': 'attr does not exist',
'attr': '_not_valid'}
])
def test_attribute_error(self, attr):
""" test that attribute of internal optimizer is correctly rerouted to
the internal optimizer
Args:
attr: attribute to test
result: result after checking attribute
"""
loss = TestLoss(1, 1, 1)
internal_optimizer = TestOptimizer()
optimizer = opt.Bolton(internal_optimizer, loss)
with self.assertRaises(AttributeError):
getattr(optimizer, attr)
if __name__ == '__main__':
test.main()