Clean up task output message handling

doc/cug.tex

@@ -3348,23 +3348,12 @@ \subsubsection{Trigger Types}
 \paragraph{Message Triggers}
 \label{MessageTriggers}
 
-Message triggers allow triggering off custom messages emitted by a task as it
-runs. {\em Message outputs} must be registered for the task in the suite
-definition, and matching messages sent back to the suite daemon by the
-task at the appropriate time. {\em Note that polling does not yet detect custom
-message output completion.} Custom output messages should normally contain the
-cycle point in order to
-distinguish between the outputs of different instances of the same task. 
-The task implementation can use \lstinline=$CYLC_TASK_CYCLE_POINT= for
-this, or \lstinline@cylc cycle-point --offset=P2M@ for an offset value.
-The matching message string registered in the suite definition, however, does
-not get interpreted by the shell, so a cycle point placeholder is used instead:
-\lstinline=[]= for the current cycle point, or for an offset \lstinline=[-P2M]=.
-
-The \lstinline=$CYLC_DIR/examples/message-triggers/= suite is a self-contained
-example that illustrates message triggering. Note that the graph trigger
-notation uses a label that selects the message registered under the task
-\lstinline=[runtime]= section.
+Tasks can also trigger off custom output messages. These must be registered in
+the \lstinline=[runtime]= section of the emitting task, and reported using the
+\lstinline=cylc message= command in task scripting. The graph trigger notation
+refers to the item name of the registered output message.
+The example suite \lstinline=$CYLC_DIR/examples/message-triggers= illustrates
+message triggering.
 
 \lstset{language=suiterc}
 \lstinputlisting{../examples/message-triggers/suite.rc}

doc/suiterc.tex

@@ -1706,26 +1706,23 @@ \subsection{[runtime]}
 
 \paragraph[{[[[}outputs{]]]}]{[runtime] \textrightarrow [[\_\_NAME\_\_]] \textrightarrow [[[outputs]]]}
 
-This section is for registering custom message outputs that other tasks can
-trigger off instead of the standard triggers. The task implementation must send
-corresponding messages using the \lstinline=cylc task message= command at the
-appropriate time. See~\ref{MessageTriggers} for more information.
+Register custom task outputs for use in message triggering in this section
+(\ref{MessageTriggers}) 
 
 \subparagraph[\_\_OUTPUT\_\_ ]{[runtime] \textrightarrow [[\_\_NAME\_\_]] \textrightarrow [[[outputs]]] \textrightarrow \_\_OUTPUT\_\_}
 
-Replace \_\_OUTPUT\_\_ with one or more labelled output messages, and use the
-labels in graph trigger notation.  Messages should contain a placeholder for
-the current cycle point (\lstinline=[]=) or some offset from it (e.g.\ \lstinline=[-P2M]=).
+Replace \_\_OUTPUT\_\_ with one or more custom task output messages
+(\ref{MessageTriggers}).  The item name is used to select the custom output
+message in graph trigger notation.
 \begin{myitemize}
     \item {\em type:} string
     \item {\em default:} (none)
     \item{ \em examples:}
 \end{myitemize}
 \begin{lstlisting}
-foo = "sea state products ready for []"
-bar = "nwp restart files ready for [-PT6H]"
+out1 = "sea state products ready"
+out2 = "NWP restart files completed"
 \end{lstlisting}
-See~\ref{MessageTriggers} for more information.
 
 \paragraph[{[[[}suite state polling{]]]}]{[runtime] \textrightarrow [[\_\_NAME\_\_]] \textrightarrow [[[suite state polling]]]}
 

examples/message-triggers/suite.rc

@@ -5,23 +5,18 @@ title = "test suite for cylc-6 message triggers"
     final cycle point = 20141201T00
     [[dependencies]]
         [[[P2M]]]
-           graph = """
-# bar triggers off message 'x' emitted by foo:
-              foo:x => bar
-# baz triggers off message 'y' emitted by the previous instance of foo:
-           foo[-P2M]:y => baz
-                  """
+           graph = """foo:out1 => bar
+                      foo[-P2M]:out2 => baz"""
 [runtime]
     [[foo]]
         script = """
-echo HELLO
-sleep 2 
-TARGET_POINT=$CYLC_TASK_CYCLE_POINT
-cylc message "file 1 for $TARGET_POINT done"
-sleep 2
-TARGET_POINT=$(cylc cycle-point --offset P2M)
-cylc message "file 2 for $TARGET_POINT done"
-sleep 2"""
+sleep 5
+cylc message "file 1 done"
+sleep 10
+cylc message "file 2 done"
+sleep 10"""
         [[[outputs]]]
-            x = "file 1 for [] done"
-            y = "file 2 for [P2M] done"
+            out1 = "file 1 done"
+            out2 = "file 2 done"
+    [[bar, baz]]
+        script = sleep 10

lib/cylc/config.py

@@ -32,12 +32,12 @@
 from isodatetime.data import Calendar
 from envvar import check_varnames, expandvars
 from copy import deepcopy, copy
-from output import output
+from message_output import MessageOutput
 from graphnode import graphnode, GraphNodeError
 from print_tree import print_tree
 from cylc.prerequisite import TriggerExpressionError
 from regpath import RegPath
-from trigger import trigger
+from task_trigger import TaskTrigger
 from parsec.util import replicate
 from cylc.task_id import TaskID
 from C3MRO import C3
@@ -1698,16 +1698,9 @@ def generate_taskdefs(self, line, left_nodes, right, section, seq,
             if self.run_mode == 'live':
                 # Record message outputs.
                 for lbl, msg in self.cfg['runtime'][name]['outputs'].items():
-                    outp = output(msg, base_interval)
-                    # Check for a cycle offset placeholder.
-                    if not re.search(r'\[[^\]]*\]', msg):
-                        print >> sys.stderr, (
-                            "Message outputs require an "
-                            "offset placeholder (e.g. '[]' or '[-P2M]'):")
-                        print >> sys.stderr, "  %s = %s" % (lbl, msg)
-                        raise SuiteConfigError(
-                            'ERROR: bad message output string')
-                    self.taskdefs[name].outputs.append(outp)
+                    outp = MessageOutput(msg, base_interval)
+                    if outp not in self.taskdefs[name].outputs:
+                        self.taskdefs[name].outputs.append(outp)
 
     def generate_triggers(self, lexpression, left_nodes, right, seq, suicide):
         if not right or not left_nodes:
@@ -1743,7 +1736,7 @@ def generate_triggers(self, lexpression, left_nodes, right, seq, suicide):
                     offset_tuple = (lnode.offset_string, None)
                 ltaskdef.intercycle_offsets.append(offset_tuple)
 
-            trig = trigger(
+            trig = TaskTrigger(
                 lnode.name, lnode.output, lnode.offset_string, cycle_point,
                 suicide, self.cfg['runtime'][lnode.name]['outputs'],
                 base_interval)

lib/cylc/message_output.py

@@ -0,0 +1,51 @@
+#!/usr/bin/env python
+
+# THIS FILE IS PART OF THE CYLC SUITE ENGINE.
+# Copyright (C) 2008-2015 NIWA
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import re
+from cycling.loader import get_interval, get_interval_cls
+from task_trigger import get_message_offset
+
+
+class MessageOutput(object):
+    """
+    A task message output.
+
+    Used to generate an output string for a message trigger at a cycle point.
+
+    TODO - these can be plain strings once the deprecated cycle point offset
+    placeholders are removed from cylc (see GitHub #1761).
+
+    """
+
+    def __init__(self, msg, base_interval=None):
+        self.msg = msg
+        self.msg_offset = get_message_offset(msg, base_interval)
+
+    def get_string(self, point):
+        """Return the message string for this cycle point.
+
+        Placeholders are replaced with the actual cycle point offset.
+
+        """
+        new_point = point
+        if self.msg_offset:
+            new_point = point + self.msg_offset
+        return re.sub('\[.*\]', str(new_point), self.msg)
+
+    def __eq__(self, other):
+        return self.msg == other.msg and self.msg_offset == other.msg_offset

lib/cylc/prerequisite.py

@@ -20,6 +20,7 @@
 import sys
 from cylc.conditional_simplifier import ConditionalSimplifier
 from cylc.cycling.loader import get_point
+from cylc.task_id import TaskID
 
 
 """A task prerequisite.
@@ -88,10 +89,12 @@ def set_condition(self, expr):
             if k in drop_these:
                 continue
             if self.start_point:
-                task = re.search(r'(.*).(.*) ', self.messages[k])
-                if task.group:
+                m = re.search(
+                    r'(' + TaskID.NAME_RE + ')\.(' +
+                    TaskID.POINT_RE + ') ', self.messages[k])
+                if m:
                     try:
-                        foo = task.group().split(".")[1].rstrip()
+                        foo = m.group().split(".")[1].rstrip()
                         if get_point(foo) < self.start_point:
                             drop_these.append(k)
                     except IndexError:

lib/cylc/task_message.py

@@ -32,7 +32,6 @@ class TaskMessage(object):
     FAILED = "failed"
     STARTED = "started"
     SUCCEEDED = "succeeded"
-    STATUSES = (STARTED, SUCCEEDED, FAILED)
 
     CYLC_JOB_PID = "CYLC_JOB_PID"
     CYLC_JOB_INIT_TIME = "CYLC_JOB_INIT_TIME"
@@ -115,7 +114,6 @@ def __init__(self, priority=NORMAL):
     def send(self, messages):
         """Send messages back to the suite."""
         self._update_job_status_file(messages)
-
         if self.mode != 'scheduler' or self.polling:
             # no suite to communicate with, just print to stdout.
             self._print_messages(messages)
@@ -310,8 +308,6 @@ def _update_job_status_file(self, messages):
                     job_status_file.write("%s=%s|%s|%s\n" % (
                         self.CYLC_MESSAGE, self.true_event_time, self.priority,
                         message))
-            if message in self.STATUSES:
-                messages[i] = "%s %s" % (self.task_id, message)
             messages[i] += ' at ' + self.true_event_time
         if job_status_file:
             try: