feat(operations): worker concurrency and job retention settings

operations/tests/test_conf.py

@@ -0,0 +1,13 @@
+from django.test import TestCase
+
+from appsettings.models import AppSettings
+from operations import utils
+
+
+class ConfTestCase(TestCase):
+    def test_defaults_and_bounds(self):
+        self.assertEqual((utils.concurrency(), utils.retention_days()), (4, 30))
+        AppSettings.objects.filter(key="WORKER_CONCURRENCY").update(value="99")
+        self.assertEqual(utils.concurrency(), 4)
+        AppSettings.objects.filter(key="WORKER_CONCURRENCY").update(value="8")
+        self.assertEqual(utils.concurrency(), 8)

operations/utils.py

@@ -1,6 +1,8 @@
 """Secrets never reach a job record, a response or a log line. What a refused
 request says about the job holding the resource: details for its owner and
-superusers, a minimal summary for everyone else."""
+superusers, a minimal summary for everyone else. Worker settings from the
+Settings page. The worker reads them itself (the settings middleware only runs
+in gunicorn)."""
 
 import re
 
@@ -8,6 +10,8 @@ from django.utils import timezone
 from django.utils.timesince import timesince
 from django.utils.translation import gettext as _
 
+from appsettings.models import AppSettings
+
 from . import jobs
 
 _NAMES = r"(?:pass|secret|token|key)\w*"
@@ -21,6 +25,8 @@ _PATTERNS = [
 ]
 _SECRET_KEY = re.compile(r"pass|secret|token|private|key$", re.I)
 
+BOUNDS = {"WORKER_CONCURRENCY": (1, 16, 4), "JOB_RETENTION_DAYS": (1, 3650, 30)}
+
 
 def safe_text(text):
     text = str(text)
@@ -60,3 +66,20 @@ def busy_message(busy, user):
         return _("%(label)s is %(state)s on this resource (started by %(user)s, %(since)s ago); "
                  "see the Jobs page.") % {**values, "user": op.username}
     return _("%(label)s is %(state)s on this resource (since %(since)s).") % values
+
+
+def _value(key):
+    low, high, default = BOUNDS[key]
+    try:
+        value = int(AppSettings.objects.get(key=key).value)
+    except (AppSettings.DoesNotExist, ValueError):
+        return default
+    return value if low <= value <= high else default
+
+
+def concurrency():
+    return _value("WORKER_CONCURRENCY")
+
+
+def retention_days():
+    return _value("JOB_RETENTION_DAYS")