Files
koin_ping_0.2.0/backend-go/internal/services/evaluator.go
2026-02-27 17:33:40 -05:00

252 lines
7.0 KiB
Go

package services
import (
"context"
"fmt"
"log"
"github.com/kjannette/koin-ping/backend-go/internal/domain"
"github.com/kjannette/koin-ping/backend-go/internal/models"
"github.com/kjannette/koin-ping/backend-go/internal/notifications"
"github.com/kjannette/koin-ping/backend-go/internal/protocols/ethereum"
"github.com/kjannette/koin-ping/backend-go/internal/wei"
)
type EvaluatorService struct {
eth ethereum.EthereumObserver
alertRules *models.AlertRuleModel
alertEvents *models.AlertEventModel
addresses *models.AddressModel
notifConfigs *models.NotificationConfigModel
smtpConfig notifications.SMTPConfig
}
func NewEvaluatorService(
eth ethereum.EthereumObserver,
alertRules *models.AlertRuleModel,
alertEvents *models.AlertEventModel,
addresses *models.AddressModel,
notifConfigs *models.NotificationConfigModel,
smtpCfg notifications.SMTPConfig,
) *EvaluatorService {
return &EvaluatorService{
eth: eth,
alertRules: alertRules,
alertEvents: alertEvents,
addresses: addresses,
notifConfigs: notifConfigs,
smtpConfig: smtpCfg,
}
}
func (s *EvaluatorService) Evaluate(ctx context.Context, observations []domain.ObservedTx) (int, error) {
alertsFired := 0
for _, obs := range observations {
fired, err := s.evaluateObservation(ctx, obs)
if err != nil {
log.Printf("Error evaluating observation for address ID %d: %v", obs.AddressID, err)
continue
}
alertsFired += fired
}
return alertsFired, nil
}
func (s *EvaluatorService) evaluateObservation(ctx context.Context, obs domain.ObservedTx) (int, error) {
rules, err := s.alertRules.ListByAddress(ctx, obs.AddressID)
if err != nil {
return 0, err
}
alertsFired := 0
for _, rule := range rules {
if !rule.Enabled {
continue
}
matches, err := s.ruleMatches(ctx, rule, obs)
if err != nil {
log.Printf("Error matching rule %d: %v", rule.ID, err)
continue
}
if matches {
if err := s.fireAlert(ctx, rule, obs); err != nil {
log.Printf("Error firing alert for rule %d: %v", rule.ID, err)
continue
}
alertsFired++
}
}
return alertsFired, nil
}
func (s *EvaluatorService) ruleMatches(ctx context.Context, rule domain.AlertRule, obs domain.ObservedTx) (bool, error) {
switch rule.Type {
case domain.AlertIncomingTx:
return obs.Direction == domain.DirectionIncoming, nil
case domain.AlertOutgoingTx:
return obs.Direction == domain.DirectionOutgoing, nil
case domain.AlertLargeTransfer:
return s.matchesLargeTransfer(rule, obs)
case domain.AlertBalanceBelow:
return s.matchesBalanceBelow(ctx, rule, obs)
default:
log.Printf("Unknown rule type: %s", rule.Type)
return false, nil
}
}
func (s *EvaluatorService) matchesLargeTransfer(rule domain.AlertRule, obs domain.ObservedTx) (bool, error) {
if rule.Threshold == nil {
return false, nil
}
thresholdWei, err := wei.FromEth(*rule.Threshold)
if err != nil {
return false, err
}
return wei.GreaterThanOrEqual(obs.Value, thresholdWei)
}
// matchesBalanceBelow only triggers after outgoing transactions, since incoming
// transactions increase balance and can't cause it to drop below threshold.
func (s *EvaluatorService) matchesBalanceBelow(ctx context.Context, rule domain.AlertRule, obs domain.ObservedTx) (bool, error) {
if rule.Threshold == nil {
return false, nil
}
if obs.Direction != domain.DirectionOutgoing {
return false, nil
}
addr, err := s.addresses.FindByID(ctx, obs.AddressID, nil)
if err != nil {
return false, err
}
if addr == nil {
log.Printf("Address ID %d not found", obs.AddressID)
return false, nil
}
balanceWei, err := s.eth.GetBalance(ctx, addr.Address)
if err != nil {
return false, err
}
thresholdWei, err := wei.FromEth(*rule.Threshold)
if err != nil {
return false, err
}
return wei.LessThan(balanceWei, thresholdWei)
}
func (s *EvaluatorService) fireAlert(ctx context.Context, rule domain.AlertRule, obs domain.ObservedTx) error {
addr, err := s.addresses.FindByID(ctx, obs.AddressID, nil)
if err != nil {
return err
}
addressLabel := "Unknown"
if addr != nil {
if addr.Label != nil {
addressLabel = *addr.Label
} else {
addressLabel = addr.Address
}
}
message := s.buildMessage(rule, obs)
txHash := &obs.Hash
_, err = s.alertEvents.Create(ctx, rule.ID, message, &addressLabel, txHash)
if err != nil {
return err
}
log.Printf("[ALERT FIRED] Rule %d (%s) - %s - TX: %s", rule.ID, rule.Type, message, obs.Hash)
if addr != nil {
go s.sendNotifications(ctx, addr.UserID, message, obs, addressLabel, rule, addr.Address)
}
return nil
}
func (s *EvaluatorService) sendNotifications(ctx context.Context, userID, message string, obs domain.ObservedTx, addressLabel string, rule domain.AlertRule, address string) {
notifConfig, err := s.notifConfigs.GetConfig(ctx, userID)
if err != nil {
log.Printf("Failed to get notification config: %v", err)
return
}
if notifConfig == nil || !notifConfig.NotificationEnabled {
return
}
meta := notifications.AlertMetadata{
TxHash: obs.Hash,
AddressLabel: addressLabel,
AlertType: string(rule.Type),
Address: address,
}
if notifConfig.DiscordWebhookURL != nil && *notifConfig.DiscordWebhookURL != "" {
sent, err := notifications.SendDiscordNotification(*notifConfig.DiscordWebhookURL, message, meta)
if err != nil || !sent {
log.Printf("Discord notification failed for user %s: %v", userID, err)
} else {
log.Printf("Discord notification sent to user %s", userID)
}
}
if notifConfig.SlackWebhookURL != nil && *notifConfig.SlackWebhookURL != "" {
sent, err := notifications.SendSlackNotification(*notifConfig.SlackWebhookURL, message, meta)
if err != nil || !sent {
log.Printf("Slack notification failed for user %s: %v", userID, err)
} else {
log.Printf("Slack notification sent to user %s", userID)
}
}
if notifConfig.Email != nil && *notifConfig.Email != "" && s.smtpConfig.IsConfigured() {
sent, err := notifications.SendEmailNotification(s.smtpConfig, *notifConfig.Email, message, meta)
if err != nil || !sent {
log.Printf("Email notification failed for user %s: %v", userID, err)
} else {
log.Printf("Email notification sent to user %s (%s)", userID, *notifConfig.Email)
}
}
}
func (s *EvaluatorService) buildMessage(rule domain.AlertRule, obs domain.ObservedTx) string {
switch rule.Type {
case domain.AlertIncomingTx:
ethStr, _ := wei.FormatAsEth(obs.Value, 4)
return fmt.Sprintf("Incoming transaction: %s received", ethStr)
case domain.AlertOutgoingTx:
ethStr, _ := wei.FormatAsEth(obs.Value, 4)
return fmt.Sprintf("Outgoing transaction: %s sent", ethStr)
case domain.AlertLargeTransfer:
ethStr, _ := wei.FormatAsEth(obs.Value, 4)
threshold := float64(0)
if rule.Threshold != nil {
threshold = *rule.Threshold
}
return fmt.Sprintf("Large transfer detected: %s (threshold: %g ETH)", ethStr, threshold)
case domain.AlertBalanceBelow:
threshold := float64(0)
if rule.Threshold != nil {
threshold = *rule.Threshold
}
return fmt.Sprintf("Balance dropped below threshold of %g ETH", threshold)
default:
return "Alert triggered"
}
}