Initial work on hooke.command_stack and hooke.playlist integration.
authorW. Trevor King <wking@drexel.edu>
Thu, 12 Aug 2010 14:26:28 +0000 (10:26 -0400)
committerW. Trevor King <wking@drexel.edu>
Thu, 12 Aug 2010 14:26:28 +0000 (10:26 -0400)
The current problem is figuring out how to run commands from a Curve
without Curves knowing about Hooke or CommandEngine instances.

hooke/command_stack.py
hooke/curve.py
hooke/playlist.py

index cebf0b9..fc8dc75 100644 (file)
 # License along with Hooke.  If not, see
 # <http://www.gnu.org/licenses/>.
 
-"""The ``command_stack`` module provides tools for managing stacks of
-:class:`~hooke.engine.CommandMessage`\s and applying those stacks to
-:class:`~hooke.curve.Curve`\s.
+"""The ``command_stack`` module provides tools for managing and
+executing stacks of :class:`~hooke.engine.CommandMessage`\s.
 """
 
-from .command import Command, Argument, Failure
-from .engine import CommandMessage
-from .playlist import NoteIndexList
+
+class CommandStack (list):
+    """Store a stack of commands.
+
+    Examples
+    --------
+    >>> from .engine import CommandMessage
+
+    Define two dummy commands for testing.
+
+    >>> class CommandA (object):
+    ...     name = 'CommandA'
+    >>> ca = CommandA()
+    >>> class CommandB (CommandA):
+    ...     name = 'CommandB'
+    >>> cb = CommandB()
+
+    Show off `CommandStack`\s functionality.
+
+    >>> c = CommandStack([CommandMessage(ca, {'param':'A'})])
+    >>> c.append(CommandMessage(cb, {'param':'B'}))
+    >>> c.append(CommandMessage(ca, {'param':'C'}))
+    >>> c.append(CommandMessage(cb, {'param':'D'}))
+
+    Implement a dummy :meth:`_execute` for testing.  This would
+    usually call :meth:`hooke.command.Command.run` with appropriate
+    arguments.
+    
+    >>> def execute(command_message):
+    ...     cm = command_message
+    ...     print 'EXECUTE', cm.command.name, cm.arguments
+    >>> c._execute = execute
+
+    >>> c.execute()  # doctest: +ELLIPSIS
+    EXECUTE CommandA {'param': 'A'}
+    EXECUTE CommandB {'param': 'B'}
+    EXECUTE CommandA {'param': 'C'}
+    EXECUTE CommandB {'param': 'D'}
+
+    :meth:`filter` allows you to select which commands get executed.
+    If, for example, you are applying a set of commands to the current
+    :class:`~hooke.curve.Curve`, you may only want to execute
+    instances of :class:`~hooke.plugin.curve.CurveCommand`.  Here we
+    only execute instances of `CommandB`.
+    
+    >>> def filter(command_message):
+    ...     return isinstance(command_message.command, CommandB)
+    >>> c.filter = filter
+
+    Apply the stack to the current curve
+    >>> c.execute()  # doctest: +ELLIPSIS
+    EXECUTE CommandB {'param': 'B'}
+    EXECUTE CommandB {'param': 'D'}
+    """
+    def execute(self, *args, **kwargs):
+        """Execute a stack of commands.
+
+        See Also
+        --------
+        _execute, filter
+        """
+        for command_message in self:
+            if self.filter(command_message) == True:
+                self._execute(command_message, *args, **kwargs)
+
+    def filter(self, command_message):
+        """Any commands in the stack that are not subclasses of
+        :class:`~hooke.plugin.curve.CurveCommand` are ignored.
+        """
+        return True
+
+    def _execute(self, command_message):
+        raise NotImplementedError()
index 7e3d084..552eda6 100644 (file)
@@ -23,6 +23,8 @@ storing force curves.
 import os.path
 import numpy
 
+from .command_stack import CommandStack
+
 
 class NotRecognized (ValueError):
     def __init__(self, curve):
@@ -144,15 +146,19 @@ class Curve (object):
     `experiment`.  These are two strings that can be used by Hooke
     commands/plugins to understand what they are looking at.
 
-    * `.info['filetype']` should contain the name of the exact
+    * :attr:`info['filetype']` should contain the name of the exact
       filetype defined by the driver (so that filetype-speciofic
       commands can know if they're dealing with the correct filetype).
-    * `.info['experiment']` should contain an instance of a
+    * :attr:`info['experiment']` should contain an instance of a
       :class:`hooke.experiment.Experiment` subclass to identify the
       experiment type.  For example, various
       :class:`hooke.driver.Driver`\s can read in force-clamp data, but
       Hooke commands could like to know if they're looking at force
       clamp data, regardless of their origin.
+
+    Another important attribute is :attr:`command_stack`, which holds
+    a :class:`~hooke.command_stack.CommandStack` listing the commands
+    that have been applied to the `Curve` since loading.
     """
     def __init__(self, path, info=None):
         #the data dictionary contains: {name of data: list of data sets [{[x], [y]}]
@@ -163,6 +169,7 @@ class Curve (object):
             info = {}
         self.info = info
         self.name = os.path.basename(path)
+        self.command_stack = CommandStack()
 
     def identify(self, drivers):
         """Identify the appropriate :class:`hooke.driver.Driver` for
@@ -181,13 +188,18 @@ class Curve (object):
                 return
         raise NotRecognized(self)
 
-    def load(self):
+    def load(self, *args, **kwargs):
         """Use the driver to read the curve into memory.
+
+        Also runs any commands in :attr:`command_stack`.  All
+        arguments are passed through to
+        :meth:`hooke.command_stack.CommandStack.execute`.
         """
         data,info = self.driver.read(self.path, self.info)
         self.data = data
         for key,value in info.items():
             self.info[key] = value
+        self.command_stack.execute(*args, **kwargs)
 
     def unload(self):
         """Release memory intensive :attr:`.data`.
index 8d889a3..906cb06 100644 (file)
@@ -107,6 +107,7 @@ class NoteIndexList (list):
             c._index = 0
         return c
 
+
 class Playlist (NoteIndexList):
     """A :class:`NoteIndexList` of :class:`hooke.curve.Curve`\s.
 
@@ -117,6 +118,8 @@ class Playlist (NoteIndexList):
         self.drivers = drivers
         self._loaded = [] # List of loaded curves, see :meth:`._setup_item`.
         self._max_loaded = 100 # curves to hold in memory simultaneously.
+        self._curve_load_args = ()
+        self._curve_load_kwargs = {}
 
     def append_curve_by_path(self, path, info=None, identify=True):
         path = os.path.normpath(path)
@@ -126,6 +129,10 @@ class Playlist (NoteIndexList):
         self.append(c)
         return c
 
+    def set_curve_load_args(self, *args, **kwargs):
+        self._curve_load_args = args
+        self._curve_load_kwargs = kwargs
+
     def _setup_item(self, curve):
         if curve != None and curve not in self._loaded:
             if curve not in self:
@@ -133,12 +140,13 @@ class Playlist (NoteIndexList):
             if curve.driver == None:
                 c.identify(self.drivers)
             if curve.data == None:
-                curve.load()
+                curve.load(*self._curve_load_args, **self._curve_load_kwargs)
             self._loaded.append(curve)
             if len(self._loaded) > self._max_loaded:
                 oldest = self._loaded.pop(0)
                 oldest.unload()
 
+
 class FilePlaylist (Playlist):
     version = '0.1'