"""SLA Engine domain models. Model inventory --------------- SLAType — enum: response / resolution / approval / assignment SLABreachStatus — enum: warning / breached / recovered SLAPolicy — core entity: tenant-scoped SLA policy definition SLATimer — per-entity SLA timer tracking (pause/resume, breach detection) SLABreach — records SLA breach events """ from __future__ import annotations from typing import ClassVar from django.contrib.contenttypes.fields import GenericForeignKey from django.contrib.contenttypes.models import ContentType from django.db import models from django.utils.translation import gettext_lazy as _ from simorgh.core.db.scoped import ScopedSoftDeleteManager from simorgh.core.models import ( SoftDeleteModel, TenantScopedModel, TimeStampedModel, UUIDModel, ) class SLAType(models.TextChoices): RESPONSE = "response", _("Response SLA") RESOLUTION = "resolution", _("Resolution SLA") APPROVAL = "approval", _("Approval SLA") ASSIGNMENT = "assignment", _("Assignment SLA") class SLABreachStatus(models.TextChoices): WARNING = "warning", _("Warning") BREACHED = "breached", _("Breached") RECOVERED = "recovered", _("Recovered") class SLAPolicy(UUIDModel, TenantScopedModel, SoftDeleteModel): """An SLA policy defining response/resolution time targets. Can be scoped to a specific entity type (content_type) and optionally filtered by priority or other JSON conditions. """ name = models.CharField(_("name"), max_length=300) description = models.TextField(_("description"), blank=True, default="") sla_type = models.CharField( _("SLA type"), max_length=16, choices=SLAType.choices, db_index=True, ) target_hours = models.DecimalField( _("target hours"), max_digits=6, decimal_places=2, help_text=_("Maximum hours allowed before breach."), ) warning_hours = models.DecimalField( _("warning hours"), max_digits=6, decimal_places=2, null=True, blank=True, help_text=_("Hours before breach to trigger a warning."), ) business_hours_only = models.BooleanField( _("business hours only"), default=True, help_text=_("Count only business hours for the SLA timer."), ) content_type = models.ForeignKey( ContentType, on_delete=models.CASCADE, null=True, blank=True, related_name="sla_policies", verbose_name=_("entity type"), help_text=_("If set, this SLA policy only applies to this entity type."), ) conditions = models.JSONField( _("conditions"), default=dict, blank=True, help_text=_("JSON conditions for matching this policy to specific entities."), ) priority = models.CharField( _("priority"), max_length=10, choices=(("low", _("Low")), ("medium", _("Medium")), ("high", _("High")), ("urgent", _("Urgent"))), blank=True, db_index=True, help_text=_("If set, this SLA only applies to entities with this priority."), ) is_active = models.BooleanField(_("active"), default=True, db_index=True) objects: ClassVar[ScopedSoftDeleteManager] = ScopedSoftDeleteManager() class Meta(TenantScopedModel.Meta): verbose_name = _("SLA policy") verbose_name_plural = _("SLA policies") ordering = ("tenant", "name") constraints = ( models.UniqueConstraint( fields=("tenant", "name"), name="sla_policy_unique_tenant_name", ), ) indexes: ClassVar = [ *TenantScopedModel.Meta.indexes, models.Index(fields=("tenant", "sla_type", "is_active"), name="sla_policy_tenant_type_active"), ] def __str__(self) -> str: return self.name class SLATimer(UUIDModel, TimeStampedModel): """An SLA timer tracking a specific entity's SLA compliance. Linked generically to any entity via content_type/object_id. Supports pause/resume for business-hours-only tracking. """ policy = models.ForeignKey( SLAPolicy, on_delete=models.PROTECT, related_name="timers", verbose_name=_("SLA policy"), ) tenant = models.ForeignKey( "tenants.Tenant", on_delete=models.CASCADE, related_name="sla_timers", verbose_name=_("tenant"), ) content_type = models.ForeignKey( ContentType, on_delete=models.CASCADE, verbose_name=_("entity type"), ) object_id = models.PositiveIntegerField(_("entity id")) content_object = GenericForeignKey("content_type", "object_id") started_at = models.DateTimeField(_("started at"), null=True, blank=True) paused_at = models.DateTimeField(_("paused at"), null=True, blank=True) accumulated_seconds = models.PositiveBigIntegerField( _("accumulated seconds"), default=0, help_text=_("Total elapsed seconds excluding pause periods."), ) target_at = models.DateTimeField( _("target at"), null=True, blank=True, help_text=_("When the SLA target is due."), ) warning_at = models.DateTimeField( _("warning at"), null=True, blank=True, help_text=_("When a warning should be triggered."), ) warning_sent = models.BooleanField(_("warning sent"), default=False, db_index=True) is_breached = models.BooleanField(_("breached"), default=False, db_index=True) breached_at = models.DateTimeField(_("breached at"), null=True, blank=True) is_recovered = models.BooleanField(_("recovered"), default=False) recovered_at = models.DateTimeField(_("recovered at"), null=True, blank=True) is_stopped = models.BooleanField(_("stopped"), default=False, db_index=True) stopped_at = models.DateTimeField(_("stopped at"), null=True, blank=True) class Meta: verbose_name = _("SLA timer") verbose_name_plural = _("SLA timers") ordering = ("-created_at",) indexes: ClassVar[list[models.Index]] = [ models.Index(fields=("tenant", "is_breached", "is_stopped"), name="sla_timer_brchd_stpd"), models.Index(fields=("tenant", "target_at"), name="sla_timer_tenant_target"), models.Index(fields=("content_type", "object_id"), name="sla_timer_content_object"), models.Index(fields=("warning_at", "warning_sent"), name="sla_timer_warning"), ] constraints = ( models.UniqueConstraint( fields=("policy", "content_type", "object_id"), name="sla_timer_unique_policy_entity", ), ) def __str__(self) -> str: return f"SLA Timer: {self.policy.name} | {self.content_type}:{self.object_id}" class SLABreach(UUIDModel, TimeStampedModel): """Records SLA breach and warning events for audit trail.""" timer = models.ForeignKey( SLATimer, on_delete=models.CASCADE, related_name="breaches", verbose_name=_("SLA timer"), ) policy = models.ForeignKey( SLAPolicy, on_delete=models.PROTECT, related_name="breaches", verbose_name=_("SLA policy"), ) tenant = models.ForeignKey( "tenants.Tenant", on_delete=models.CASCADE, related_name="sla_breaches", verbose_name=_("tenant"), ) content_type = models.ForeignKey( ContentType, on_delete=models.SET_NULL, null=True, verbose_name=_("entity type"), ) object_id = models.PositiveIntegerField(_("entity id"), null=True) status = models.CharField( _("status"), max_length=16, choices=SLABreachStatus.choices, db_index=True, ) occurred_at = models.DateTimeField(_("occurred at"), default=None, db_index=True) notes = models.TextField(_("notes"), blank=True, default="") class Meta: verbose_name = _("SLA breach") verbose_name_plural = _("SLA breaches") ordering = ("-occurred_at",) indexes: ClassVar[list[models.Index]] = [ models.Index(fields=("tenant", "status"), name="sla_breach_tenant_status"), models.Index(fields=("tenant", "occurred_at"), name="sla_breach_tenant_occurred"), ] def __str__(self) -> str: return f"SLA Breach: {self.get_status_display()} | {self.policy.name}"