Refactoring of the inputs

beat/backend/python/inputs.py

@@ -36,8 +36,11 @@ import six
 import zmq
 
 
-class Input:
-    """Represents the input of a processing block
+#----------------------------------------------------------
+
+
+class BaseInput(object):
+    """Base class for all the kinds of input of a processing block
 
     A list of those inputs must be provided to the algorithms (see
     :py:class:`beat.backend.python.inputs.InputList`)
@@ -49,9 +52,6 @@ class Input:
 
       data_format (str): Data format accepted by the input
 
-      data_source (beat.core.platform.data.DataSource): Source of data to be used
-        by the input
-
 
     Attributes:
 
@@ -70,13 +70,14 @@ class Input:
 
       data_format (str): Data format accepted by the input
 
-      data_source (beat.core.data.DataSource): Source of data used by the output
+      data_same_as_previous (bool): Indicates if the last block of data received
+        was changed (see the section *Inputs synchronization* of the User's Guide)
 
       nb_data_blocks_read (int): Number of data blocks read so far
 
     """
 
-    def __init__(self, name, data_format, data_source):
+    def __init__(self, name, data_format):
 
         self.group                 = None
         self.name                  = str(name)
@@ -85,7 +86,6 @@ class Input:
         self.data_index_end        = -1
         self.data_same_as_previous = True
         self.data_format           = data_format
-        self.data_source           = data_source
         self.nb_data_blocks_read   = 0
 
 
@@ -101,7 +101,7 @@ class Input:
     def hasMoreData(self):
         """Indicates if there is more data to process on the input"""
 
-        return self.data_source.hasMoreData()
+        raise NotImplemented
 
 
     def hasDataChanged(self):
@@ -111,6 +111,51 @@ class Input:
         return not self.data_same_as_previous
 
 
+    def next(self):
+        """Retrieves the next block of data"""
+
+        raise NotImplemented
+
+
+#----------------------------------------------------------
+
+
+class Input(BaseInput):
+    """Represents an input of a processing block that receive data from a
+    data source
+
+    A list of those inputs must be provided to the algorithms (see
+    :py:class:`beat.backend.python.inputs.InputList`)
+
+
+    Parameters:
+
+      name (str): Name of the input
+
+      data_format (str): Data format accepted by the input
+
+      data_source (beat.core.platform.data.DataSource): Source of data to be used
+        by the input
+
+
+    Attributes:
+
+      data_source (beat.core.data.DataSource): Source of data used by the output
+
+    """
+
+    def __init__(self, name, data_format, data_source):
+        super(Input, self).__init__(name, data_format)
+
+        self.data_source = data_source
+
+
+    def hasMoreData(self):
+        """Indicates if there is more data to process on the input"""
+
+        return self.data_source.hasMoreData()
+
+
     def next(self):
         """Retrieves the next block of data"""
 
@@ -158,7 +203,7 @@ def process_error(socket):
 #----------------------------------------------------------
 
 
-class RemoteInput:
+class RemoteInput(BaseInput):
     """Allows to access the input of a processing block, via a socket.
 
     The other end of the socket must be managed by a message handler (see
@@ -188,36 +233,11 @@ class RemoteInput:
     """
 
     def __init__(self, name, data_format, socket, unpack=True):
+        super(RemoteInput, self).__init__(name, data_format)
 
-        self.name = str(name)
-        self.data_format = data_format
-        self.socket = socket
-        self.data = None
-        self.data_index = -1
-        self.data_index_end = -1
-        self.group = None
-        self.comm_time = 0. #total time spent on communication
-        self.nb_data_blocks_read = 0
-        self._unpack = unpack
-
-
-    def isDataUnitDone(self):
-        """Indicates if the current data unit will change at the next iteration"""
-
-        logger.debug('send: (idd) is-dataunit-done %s', self.name)
-
-        _start = time.time()
-
-        self.socket.send('idd', zmq.SNDMORE)
-        self.socket.send(self.group.channel, zmq.SNDMORE)
-        self.socket.send(self.name)
-
-        answer = self.socket.recv()
-
-        self.comm_time += time.time() - _start
-        logger.debug('recv: %s', answer)
-
-        return answer == 'tru'
+        self.socket    = socket
+        self.comm_time = 0.0     # Total time spent on communication
+        self._unpack   = unpack
 
 
     def hasMoreData(self):
@@ -242,29 +262,6 @@ class RemoteInput:
         return answer == 'tru'
 
 
-    def hasDataChanged(self):
-        """Indicates if the current data unit is different than the one at the
-        previous iteration"""
-
-        logger.debug('send: (hdc) has-data-changed %s %s', self.group.channel, self.name)
-
-        _start = time.time()
-
-        self.socket.send('hdc', zmq.SNDMORE)
-        self.socket.send(self.group.channel, zmq.SNDMORE)
-        self.socket.send(self.name)
-
-        answer = self.socket.recv()
-
-        self.comm_time += time.time() - _start
-        logger.debug('recv: %s', answer)
-
-        if answer == 'err':
-            process_error(self.socket)
-
-        return answer == 'tru'
-
-
     def next(self):
         """Retrieves the next block of data"""
 
@@ -289,6 +286,8 @@ class RemoteInput:
         self.comm_time += time.time() - _start
         self.nb_data_blocks_read += 1
 
+        self.data_same_as_previous = False
+
 
     def unpack(self, packed):
         """Receives data through socket"""

beat/backend/python/message_handler.py

@@ -75,8 +75,6 @@ class MessageHandler(threading.Thread):
         self.callbacks = dict(
             nxt = self.next,
             hmd = self.has_more_data,
-            hdc = self.has_data_changed,
-            idd = self.is_dataunit_done,
             don = self.done,
             err = self.error,
         )
@@ -252,26 +250,6 @@ class MessageHandler(threading.Thread):
         self.socket.send(what)
 
 
-    def has_data_changed(self, channel, name):
-        """Syntax: hdc channel name"""
-
-        logger.debug('recv: hdc %s %s', channel, name)
-        input_candidate = self._get_input_candidate(channel, name)
-        what = 'tru' if input_candidate.hasDataChanged() else 'fal'
-        logger.debug('send: %s', what)
-        self.socket.send(what)
-
-
-    def is_dataunit_done(self, channel, name):
-        """Syntax: idd channel name"""
-
-        logger.debug('recv: idd %s %s', channel, name)
-        input_candidate = self._get_input_candidate(channel, name)
-        what = 'tru' if input_candidate.isDataUnitDone() else 'fal'
-        logger.debug('send: %s', what)
-        self.socket.send(what)
-
-
     def _acknowledge(self):
 
         logger.debug('send: ack')