Implement gathering overall task capacity

For use when running/planning jobs

awx/api/views.py

@@ -178,7 +178,7 @@ class ApiV1PingView(APIView):
 
         response['instances'] = []
         for instance in Instance.objects.all():
-            response['instances'].append(dict(node=instance.hostname, heartbeat=instance.modified))
+            response['instances'].append(dict(node=instance.hostname, heartbeat=instance.modified, capacity=instance.capacity))
             response['instances'].sort()
         return Response(response)
 

awx/main/managers.py

@@ -4,6 +4,7 @@
 import sys
 
 from django.db import models
+from django.db.models import Sum
 from django.conf import settings
 
 
@@ -40,6 +41,9 @@ class InstanceManager(models.Manager):
         """Return count of active Tower nodes for licensing."""
         return self.all().count()
 
+    def total_capacity(self):
+        return self.aggregate(total_capacity=Sum('capacity'))['total_capacity']
+
     def my_role(self):
         # NOTE: TODO: Likely to repurpose this once standalone ramparts are a thing
         return "tower"

awx/main/migrations/0048_310_instance_capacity.py

@@ -0,0 +1,19 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('main', '0047_v310_tower_state'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='instance',
+            name='capacity',
+            field=models.PositiveIntegerField(default=100, editable=False),
+        ),
+    ]

awx/main/models/ha.py

@@ -26,6 +26,10 @@ class Instance(models.Model):
     hostname = models.CharField(max_length=250, unique=True)
     created = models.DateTimeField(auto_now_add=True)
     modified = models.DateTimeField(auto_now=True)
+    capacity = models.PositiveIntegerField(
+        default=100,
+        editable=False,
+    )
 
     class Meta:
         app_label = 'main'

awx/main/scheduler/__init__.py

@@ -37,7 +37,7 @@ logger = logging.getLogger('awx.main.scheduler')
 class TaskManager():
     def __init__(self):
         self.graph = DependencyGraph()
-        self.capacity_total = 200
+        self.capacity_total = Instance.objects.total_capacity()
         self.capacity_used = 0
 
     def get_tasks(self):
@@ -152,7 +152,7 @@ class TaskManager():
                 map(lambda at: active_tasks.add(at['id']), active_task_queues[queue])
         else:
             if not hasattr(settings, 'CELERY_UNIT_TEST'):
-                return None
+                return (None, None)
 
         return (active_task_queues, active_tasks)
 

awx/main/tasks.py

@@ -51,7 +51,7 @@ from awx.main.queue import CallbackQueueDispatcher
 from awx.main.task_engine import TaskEnhancer
 from awx.main.utils import (get_ansible_version, get_ssh_version, decrypt_field, update_scm_url,
                             check_proot_installed, build_proot_temp_dir, wrap_args_with_proot,
-                            OutputEventFilter)
+                            get_system_task_capacity, OutputEventFilter) 
 from awx.main.consumers import emit_channel_notification
 
 __all__ = ['RunJob', 'RunSystemJob', 'RunProjectUpdate', 'RunInventoryUpdate',
@@ -131,6 +131,7 @@ def cluster_node_heartbeat(self):
     inst = Instance.objects.filter(hostname=settings.CLUSTER_HOST_ID)
     if inst.exists():
         inst = inst[0]
+        inst.capacity = get_system_task_capacity()
         inst.save()
         return
     raise RuntimeError("Cluster Host Not Found: {}".format(settings.CLUSTER_HOST_ID))