always serialize the function using cloudpickle (#281)

This was a suggestion of @jbweston some time ago.

Using this, the leaners are picklable regardless of the serialization package chosen.

Author: basnijholt

adaptive/learner/average_learner.py

@@ -1,5 +1,6 @@
 from math import sqrt
 
+import cloudpickle
 import numpy as np
 
 from adaptive.learner.base_learner import BaseLearner
@@ -151,7 +152,7 @@ def _set_data(self, data):
 
     def __getstate__(self):
         return (
-            self.function,
+            cloudpickle.dumps(self.function),
             self.atol,
             self.rtol,
             self.min_npoints,
@@ -160,5 +161,6 @@ def __getstate__(self):
 
     def __setstate__(self, state):
         function, atol, rtol, min_npoints, data = state
+        function = cloudpickle.loads(function)
         self.__init__(function, atol, rtol, min_npoints)
         self._set_data(data)

adaptive/learner/integrator_learner.py

@@ -5,6 +5,7 @@
 from math import sqrt
 from operator import attrgetter
 
+import cloudpickle
 import numpy as np
 from scipy.linalg import norm
 from sortedcontainers import SortedSet
@@ -594,13 +595,14 @@ def _set_data(self, data):
 
     def __getstate__(self):
         return (
-            self.function,
+            cloudpickle.dumps(self.function),
             self.bounds,
             self.tol,
             self._get_data(),
         )
 
     def __setstate__(self, state):
         function, bounds, tol, data = state
+        function = cloudpickle.loads(function)
         self.__init__(function, bounds, tol)
         self._set_data(data)

adaptive/learner/learner1D.py

@@ -3,6 +3,7 @@
 from collections.abc import Iterable
 from copy import deepcopy
 
+import cloudpickle
 import numpy as np
 import sortedcollections
 import sortedcontainers
@@ -634,7 +635,7 @@ def _set_data(self, data):
 
     def __getstate__(self):
         return (
-            self.function,
+            cloudpickle.dumps(self.function),
             self.bounds,
             self.loss_per_interval,
             dict(self.losses),  # SortedDict cannot be pickled
@@ -644,6 +645,7 @@ def __getstate__(self):
 
     def __setstate__(self, state):
         function, bounds, loss_per_interval, losses, losses_combined, data = state
+        function = cloudpickle.loads(function)
         self.__init__(function, bounds, loss_per_interval)
         self._set_data(data)
         self.losses.update(losses)

adaptive/learner/learner2D.py

@@ -4,6 +4,7 @@
 from copy import copy
 from math import sqrt
 
+import cloudpickle
 import numpy as np
 from scipy import interpolate
 
@@ -709,7 +710,7 @@ def _set_data(self, data):
 
     def __getstate__(self):
         return (
-            self.function,
+            cloudpickle.dumps(self.function),
             self.bounds,
             self.loss_per_triangle,
             self._stack,
@@ -718,6 +719,7 @@ def __getstate__(self):
 
     def __setstate__(self, state):
         function, bounds, loss_per_triangle, _stack, data = state
+        function = cloudpickle.loads(function)
         self.__init__(function, bounds, loss_per_triangle)
         self._set_data(data)
         self._stack = _stack

adaptive/learner/sequence_learner.py

@@ -1,5 +1,6 @@
 from copy import copy
 
+import cloudpickle
 from sortedcontainers import SortedDict, SortedSet
 
 from adaptive.learner.base_learner import BaseLearner
@@ -131,12 +132,13 @@ def _set_data(self, data):
 
     def __getstate__(self):
         return (
-            self._original_function,
+            cloudpickle.dumps(self._original_function),
             self.sequence,
             self._get_data(),
         )
 
     def __setstate__(self, state):
         function, sequence, data = state
+        function = cloudpickle.loads(function)
         self.__init__(function, sequence)
         self._set_data(data)

setup.py

@@ -29,6 +29,7 @@ def get_version_and_cmdclass(package_name):
     "sortedcollections >= 1.1",
     "sortedcontainers >= 2.0",
     "atomicwrites",
+    "cloudpickle",
 ]
 
 extras_require = {
@@ -51,7 +52,6 @@ def get_version_and_cmdclass(package_name):
         "pre_commit",
     ],
     "other": [
-        "cloudpickle",
         "dill",
         "distributed",
         "ipyparallel>=6.2.5",  # because of https://github.com/ipython/ipyparallel/issues/404