feat: add support for terminate

.devcontainer/Dockerfile

@@ -23,7 +23,7 @@ RUN curl -OL https://github.com/protocolbuffers/protobuf/releases/download/v28.2
 
 # For easier Python development.
 RUN python3 -m pip install IPython && \
-    python3 -m pip install -r /requirements.txt
+    python3 -m pip install -r /requirements.txt && \
     python3 -m pip install -r /dev-requirements.txt
 
 # Assuming installing to /usr/local

README.md

@@ -66,6 +66,7 @@ Note that yes, this means "submit" is both an action and an event.
 The design of a rule is to have an action, and the action is something your ensemble can be tasked to do when an event is triggered. Right now we support the following:
 
 - **submit**: submit a job
+- **terminate**: terminate the member. This is usually what you want to call to have the entire thing exit on 0
 - **custom**: run a custom function that will receive known kwargs, and then should return an action (read more below)
 
 We see "submit" as two examples in the above, which is a common thing you'd want to do! For each action, you should minimally define the "name" and a "label" that typically corresponds to a job group.
@@ -161,6 +162,9 @@ ensemble run examples/backoff-example.yaml
 
 # This shows a custom action
 ensemble run examples/custom-action-example.yaml
+
+# This shows termination, which is necessary for when you want an exit
+ensemble run examples/terminate-example.yaml
 ```
 
 Right now, this will run any rules with "start" triggers, which for this hello world example includes a few hello world jobs! You'll then be able to watch and see flux events coming in!

ensemble/__init__.py

@@ -1 +1 @@
-__version__ = "0.0.14"
+__version__ = "0.0.15"

ensemble/config/types.py

@@ -1,4 +1,4 @@
-valid_actions = ["submit", "custom"]
+import ensemble.defaults as defaults
 
 
 class Rule:
@@ -29,7 +29,7 @@ def validate(self):
         Validate the rule and associated action
         """
         # Is the action name valid?
-        if self.action.name not in valid_actions:
+        if self.action.name not in defaults.valid_actions:
             raise ValueError(
                 f"Rule trigger {self.trigger} has invalid action name {self.action.name}"
             )

ensemble/defaults.py

@@ -1,6 +1,8 @@
 workers = 10
 port = 50051
 
+valid_actions = ["submit", "custom", "terminate"]
+
 job_events = [
     "job-depend",
     "job-sched",

ensemble/members/base.py

@@ -29,6 +29,14 @@ def __init__(self, **options):
     def name(self):
         raise NotImplementedError
 
+    def terminate(self):
+        """
+        Custom termination function
+
+        Often the executor needs custom logic to work.
+        """
+        pass
+
     def record_metrics(self, event):
         """
         Record group metrics for the event.
@@ -95,7 +103,13 @@ def execute_action(self, rule, record=None):
 
         if rule.action.name == "custom":
             self.announce(f"   custom {rule.action.label}")
-            self.custom_action(rule, record)
+            return self.custom_action(rule, record)
+
+        # Note that terminate exits but does not otherwise touch
+        # the queue, etc. Given a reactor, we should just stop it
+        if rule.action.name == "terminate":
+            self.announce("   terminate ensemble session")
+            self.terminate()
 
     def execute_metric_action(self, rule, record=None):
         """

ensemble/members/flux/queue.py

@@ -93,13 +93,19 @@ def __init__(
     def name(self):
         return "FluxQueue"
 
+    def terminate(self):
+        """
+        Custom termination function for flux.
+        """
+        self.handle.reactor_stop()
+
     def record_metrics(self, record):
         """
         Parse a Flux event and record metrics for the group.
         """
         # If we are picking up a queue backlog, we might be missing the id
-        # An alternative would be to assume the job isn't of interest and
-        # return early, but let's assume it is for now.
+        # We have to assume we are only interested in the context that is
+        # seen by the ensemble runner.
         if record["id"] not in self.jobids:
             return
 
@@ -127,8 +133,6 @@ def record_metrics(self, record):
         for rule in self.iter_rules("metric"):
             self.execute_rule(rule, record)
 
-        # TODO custom triggers -> actions!
-
     def record_start_metrics(self, event, record):
         """
         We typically want to keep the job start time for the

examples/terminate-example.yaml

@@ -0,0 +1,39 @@
+# Termination is necessary if you want the event loop to end (and exit with 0)
+logging:
+  debug: false
+
+# I made these the size of the cluster so we trigger scaling at least once
+# We currently assume these are uniform (so no order enforced beyond the listing here)
+jobs:
+  - name: echo
+    command: echo hello world
+    count: 5
+    nodes: 1
+  - name: sleep
+    command: sleep 10
+    count: 5
+    nodes: 1
+
+rules:
+  # 1. This rule says to submit the sleep jobs when we start
+  - trigger: start
+    action:
+      name: submit
+      label: sleep
+
+  # This says to submit the echo hello world jobs when we have 3
+  # successfully completed sleep jobs. This dot notation is a path into the
+  # models data structure.
+  - trigger: metric
+    name: count.sleep.success
+    when: 3
+    action:
+      name: submit
+      label: echo
+
+  # Terminate when we have 5 successful echo jobs
+  - trigger: metric
+    name: count.echo.success
+    when: 5
+    action:
+      name: terminate