Mar 03 2026: implemented SLA issue tracking & enhanced Dashboard

app/utils/sla.py

@@ -0,0 +1,80 @@
+"""
+sla.py
+------
+Issue SLA (Service Level Agreement) helpers.
+
+SLA thresholds define the maximum number of hours an issue of a given
+severity may remain unresolved before it is considered breached.
+
+Statuses
+--------
+ok        — within the allowed window
+at_risk   — past 75% of the allowed window but not yet breached
+breached  — past the deadline
+None      — issue is already resolved; SLA no longer applies
+"""
+
+from datetime import timedelta
+from app.utils.time_utils import now_eastern
+
+# ── Configurable thresholds (hours) ──────────────────────────────────────────
+SLA_HOURS = {
+    'critical': 4,
+    'high':     24,
+    'medium':   72,
+    'low':      168,   # 7 days
+}
+
+# Fraction of the window at which an issue becomes "at risk"
+AT_RISK_THRESHOLD = 0.75
+
+
+def sla_deadline(issue):
+    """
+    Return the datetime by which the issue must be resolved,
+    or None if the severity is not recognised.
+    """
+    hours = SLA_HOURS.get(issue.severity)
+    if hours is None:
+        return None
+    return issue.reported_at + timedelta(hours=hours)
+
+
+def sla_status(issue):
+    """
+    Return one of: 'ok', 'at_risk', 'breached', or None.
+
+    None is returned when the issue is already resolved — SLA no longer
+    applies.  None is also returned for unrecognised severity values.
+    """
+    if issue.status == 'resolved':
+        return None
+
+    hours = SLA_HOURS.get(issue.severity)
+    if hours is None:
+        return None
+
+    deadline   = issue.reported_at + timedelta(hours=hours)
+    at_risk_at = issue.reported_at + timedelta(hours=hours * AT_RISK_THRESHOLD)
+    now        = now_eastern()
+
+    if now >= deadline:
+        return 'breached'
+    if now >= at_risk_at:
+        return 'at_risk'
+    return 'ok'
+
+
+def sla_hours_remaining(issue):
+    """
+    Return the number of hours remaining before the SLA deadline.
+    Negative values indicate the deadline has already passed.
+    Returns None for resolved issues or unrecognised severities.
+    """
+    if issue.status == 'resolved':
+        return None
+    deadline = sla_deadline(issue)
+    if deadline is None:
+        return None
+    delta = deadline - now_eastern()
+    return round(delta.total_seconds() / 3600, 1)