Method selectByRules

internal/router/rule_router.go:53–93

(tenant config.TenantConfig, req types.AIRequest, state types.RuntimeState)

}

func (r *RuleRouter) selectByRules(tenant config.TenantConfig, req types.AIRequest, state types.RuntimeState) (types.RouteDecision, error) {
	_ = tenant

	for _, rule := range r.cfg.Routing.Rules {
		if !matchesRule(rule, tenant, req) {
			continue
		}

		backend, ok := r.cfg.BackendByName(rule.UseBackend)
		if !ok {
			return types.RouteDecision{}, fmt.Errorf("rule %q references unknown backend %q", rule.Name, rule.UseBackend)
		}
		if !backendSelectable(state, backend.Name) {
			continue
		}

		return types.RouteDecision{
			BackendName:   backend.Name,
			Reason:        rule.Name,
			EstimatedCost: backend.Cost.Unit,
		}, nil
	}

	backend, ok := r.cfg.BackendByName(r.cfg.Routing.DefaultBackend)
	if !ok {
		return types.RouteDecision{}, fmt.Errorf("default backend %q not found", r.cfg.Routing.DefaultBackend)
	}
	if backendSelectable(state, backend.Name) {
		return types.RouteDecision{
			BackendName:   backend.Name,
			Reason:        "default-backend",
			EstimatedCost: backend.Cost.Unit,
		}, nil
	}

	if d, ok := r.firstHealthyBackend(state); ok {
		return d, nil
	}

	return types.RouteDecision{}, fmt.Errorf("no healthy backend available")
}

func (r *RuleRouter) firstHealthyBackend(state types.RuntimeState) (types.RouteDecision, bool) {
	for _, backend := range r.cfg.Backends {