[ENH] Restructure of pipeline engine

nipype/caching/memory.py

@@ -21,7 +21,7 @@
 
 from ..interfaces.base import BaseInterface
 from ..pipeline.engine import Node
-from ..pipeline.utils import modify_paths
+from ..pipeline.engine.utils import modify_paths
 
 ################################################################################
 # PipeFunc object: callable interface to nipype.interface objects

nipype/caching/tests/test_memory.py

@@ -7,7 +7,7 @@
 from nose.tools import assert_equal
 
 from .. import Memory
-from ...pipeline.tests.test_engine import TestInterface
+from ...pipeline.engine.tests.test_engine import TestInterface
 
 from ... import config
 config.set_default_config()

nipype/pipeline/engine/__init__.py

@@ -0,0 +1,14 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+# emacs: -*- mode: python; py-indent-offset: 4; indent-tabs-mode: nil -*-
+# vi: set ft=python sts=4 ts=4 sw=4 et:
+"""
+Package contains modules for generating pipelines using interfaces
+
+"""
+
+from __future__ import absolute_import
+__docformat__ = 'restructuredtext'
+from .workflows import Workflow
+from .nodes import Node, MapNode, JoinNode
+from .utils import generate_expanded_graph

nipype/pipeline/engine/base.py

@@ -0,0 +1,125 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+# emacs: -*- mode: python; py-indent-offset: 4; indent-tabs-mode: nil -*-
+# vi: set ft=python sts=4 ts=4 sw=4 et:
+"""Defines functionality for pipelined execution of interfaces
+
+The `EngineBase` class implements the more general view of a task.
+
+  .. testsetup::
+     # Change directory to provide relative paths for doctests
+     import os
+     filepath = os.path.dirname(os.path.realpath( __file__ ))
+     datadir = os.path.realpath(os.path.join(filepath, '../../testing/data'))
+     os.chdir(datadir)
+
+"""
+
+from future import standard_library
+standard_library.install_aliases()
+from builtins import object
+
+try:
+    from collections import OrderedDict
+except ImportError:
+    from ordereddict import OrderedDict
+
+from copy import deepcopy
+import re
+import numpy as np
+from ...interfaces.traits_extension import traits, Undefined
+from ...interfaces.base import DynamicTraitedSpec
+from ...utils.filemanip import loadpkl, savepkl
+
+from ... import logging
+logger = logging.getLogger('workflow')
+
+
+class EngineBase(object):
+    """Defines common attributes and functions for workflows and nodes."""
+
+    def __init__(self, name=None, base_dir=None):
+        """ Initialize base parameters of a workflow or node
+
+        Parameters
+        ----------
+        name : string (mandatory)
+            Name of this node. Name must be alphanumeric and not contain any
+            special characters (e.g., '.', '@').
+        base_dir : string
+            base output directory (will be hashed before creations)
+            default=None, which results in the use of mkdtemp
+
+        """
+        self.base_dir = base_dir
+        self.config = None
+        self._verify_name(name)
+        self.name = name
+        # for compatibility with node expansion using iterables
+        self._id = self.name
+        self._hierarchy = None
+
+    @property
+    def inputs(self):
+        raise NotImplementedError
+
+    @property
+    def outputs(self):
+        raise NotImplementedError
+
+    @property
+    def fullname(self):
+        fullname = self.name
+        if self._hierarchy:
+            fullname = self._hierarchy + '.' + self.name
+        return fullname
+
+    def clone(self, name):
+        """Clone an EngineBase object
+
+        Parameters
+        ----------
+
+        name : string (mandatory)
+            A clone of node or workflow must have a new name
+        """
+        if (name is None) or (name == self.name):
+            raise Exception('Cloning requires a new name')
+        self._verify_name(name)
+        clone = deepcopy(self)
+        clone.name = name
+        clone._id = name
+        clone._hierarchy = None
+        return clone
+
+    def _check_outputs(self, parameter):
+        return hasattr(self.outputs, parameter)
+
+    def _check_inputs(self, parameter):
+        if isinstance(self.inputs, DynamicTraitedSpec):
+            return True
+        return hasattr(self.inputs, parameter)
+
+    def _verify_name(self, name):
+        valid_name = bool(re.match('^[\w-]+$', name))
+        if not valid_name:
+            raise ValueError('[Workflow|Node] name \'%s\' contains'
+                             ' special characters' % name)
+
+    def __repr__(self):
+        if self._hierarchy:
+            return '.'.join((self._hierarchy, self._id))
+        else:
+            return self._id
+
+    def save(self, filename=None):
+        if filename is None:
+            filename = 'temp.pklz'
+        savepkl(filename, self)
+
+    def load(self, filename):
+        if '.npz' in filename:
+            DeprecationWarning(('npz files will be deprecated in the next '
+                                'release. you can use numpy to open them.'))
+            return np.load(filename)
+        return loadpkl(filename)