// ensureCheckTransaction is used as the inner method to handle inserting
// a health check into the state store. It ensures safety against inserting
// checks with no matching node or service.
func (s *StateStore) ensureCheckTxn(tx *memdb.Txn, idx uint64, watches *DumbWatchManager,
hc *structs.HealthCheck) error {
// Check if we have an existing health check
existing, err := tx.First("checks", "id", hc.Node, string(hc.CheckID))
if err != nil {
return fmt.Errorf("failed health check lookup: %s", err)
}
// Set the indexes
if existing != nil {
hc.CreateIndex = existing.(*structs.HealthCheck).CreateIndex
hc.ModifyIndex = idx
} else {
hc.CreateIndex = idx
hc.ModifyIndex = idx
}
// Use the default check status if none was provided
if hc.Status == "" {
hc.Status = structs.HealthCritical
}
// Get the node
node, err := tx.First("nodes", "id", hc.Node)
if err != nil {
return fmt.Errorf("failed node lookup: %s", err)
}
if node == nil {
return ErrMissingNode
}
// If the check is associated with a service, check that we have
// a registration for the service.
if hc.ServiceID != "" {
service, err := tx.First("services", "id", hc.Node, hc.ServiceID)
if err != nil {
return fmt.Errorf("failed service lookup: %s", err)
}
if service == nil {
return ErrMissingService
}
// Copy in the service name
hc.ServiceName = service.(*structs.ServiceNode).ServiceName
}
// Delete any sessions for this check if the health is critical.
if hc.Status == structs.HealthCritical {
mappings, err := tx.Get("session_checks", "node_check", hc.Node, string(hc.CheckID))
if err != nil {
return fmt.Errorf("failed session checks lookup: %s", err)
}
var ids []string
for mapping := mappings.Next(); mapping != nil; mapping = mappings.Next() {
ids = append(ids, mapping.(*sessionCheck).Session)
}
// Delete the session in a separate loop so we don't trash the
// iterator.
watches := NewDumbWatchManager(s.tableWatches)
for _, id := range ids {
if err := s.deleteSessionTxn(tx, idx, watches, id); err != nil {
return fmt.Errorf("failed deleting session: %s", err)
}
}
tx.Defer(func() { watches.Notify() })
}
// Persist the check registration in the db.
if err := tx.Insert("checks", hc); err != nil {
return fmt.Errorf("failed inserting check: %s", err)
}
if err := tx.Insert("index", &IndexEntry{"checks", idx}); err != nil {
return fmt.Errorf("failed updating index: %s", err)
}
watches.Arm("checks")
return nil
}
