feat: initial commit — uptime monitor (forked from go-upkeep)

Go-based uptime monitor with SQLite/Postgres storage, TUI dashboard,
SSH server, alerting, and clustering support.

internal/alert/alert.go

@@ -0,0 +1,84 @@
+package alert
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"go-upkeep/internal/models"
+	"net/http"
+	"net/smtp"
+)
+
+type Provider interface {
+	Send(title, message string) error
+}
+
+func GetProvider(cfg models.AlertConfig) Provider {
+	switch cfg.Type {
+	case "discord":
+		return &DiscordProvider{URL: cfg.Settings["url"]}
+	case "slack":
+		return &SlackProvider{URL: cfg.Settings["url"]}
+	case "webhook":
+		// Generic Webhook
+		return &WebhookProvider{URL: cfg.Settings["url"]}
+	case "email":
+		port := "25"
+		if p, ok := cfg.Settings["port"]; ok { port = p }
+		return &EmailProvider{
+			Host: cfg.Settings["host"],
+			Port: port,
+			User: cfg.Settings["user"],
+			Pass: cfg.Settings["pass"],
+			To:   cfg.Settings["to"],
+			From: cfg.Settings["from"],
+		}
+	default:
+		return nil
+	}
+}
+
+// --- DISCORD ---
+type DiscordProvider struct{ URL string }
+func (d *DiscordProvider) Send(title, message string) error {
+	payload := map[string]string{"content": fmt.Sprintf("**%s**\n%s", title, message)}
+	jsonValue, _ := json.Marshal(payload)
+	_, err := http.Post(d.URL, "application/json", bytes.NewBuffer(jsonValue))
+	return err
+}
+
+// --- SLACK ---
+type SlackProvider struct{ URL string }
+func (s *SlackProvider) Send(title, message string) error {
+	payload := map[string]string{"text": fmt.Sprintf("*%s*\n%s", title, message)}
+	jsonValue, _ := json.Marshal(payload)
+	_, err := http.Post(s.URL, "application/json", bytes.NewBuffer(jsonValue))
+	return err
+}
+
+// --- GENERIC WEBHOOK ---
+type WebhookProvider struct{ URL string }
+func (w *WebhookProvider) Send(title, message string) error {
+	// Sends a standard JSON payload
+	payload := map[string]string{
+		"title":   title,
+		"message": message,
+		"status":  "alert",
+	}
+	jsonValue, _ := json.Marshal(payload)
+	_, err := http.Post(w.URL, "application/json", bytes.NewBuffer(jsonValue))
+	return err
+}
+
+// --- EMAIL ---
+type EmailProvider struct {
+	Host, Port, User, Pass, To, From string
+}
+func (e *EmailProvider) Send(title, message string) error {
+	auth := smtp.PlainAuth("", e.User, e.Pass, e.Host)
+	msg := []byte("To: " + e.To + "\r\n" +
+		"Subject: Go-Upkeep: " + title + "\r\n" +
+		"\r\n" +
+		message + "\r\n")
+	return smtp.SendMail(e.Host+":"+e.Port, auth, e.From, []string{e.To}, msg)
+}