init work of uptime

internal/monitor/monitor.go

@@ -0,0 +1,59 @@
+package monitor
+
+import (
+	"fmt"
+	"time"
+
+	"arclineit/arcline-uptime/internal/config"
+)
+
+// Result is returned by every Checker after a single probe.
+type Result struct {
+	MonitorName  string
+	Up           bool
+	StatusCode   int // HTTP only; 0 for TCP/TLS/DNS
+	ResponseTime time.Duration
+	Error        string    // empty when Up == true
+	CheckedAt    time.Time
+}
+
+// Checker probes one endpoint.
+type Checker interface {
+	Name()     string
+	Check()    Result
+	Interval() time.Duration // per-monitor interval; 0 means use the global default
+}
+
+// BuildCheckers constructs one Checker per MonitorConfig entry.
+// globalTimeout is the fallback when a monitor's own Timeout is 0.
+func BuildCheckers(monitors []config.MonitorConfig, globalTimeout time.Duration) ([]Checker, error) {
+	checkers := make([]Checker, 0, len(monitors))
+	for _, m := range monitors {
+		timeout := globalTimeout
+		if m.Timeout > 0 {
+			timeout = time.Duration(m.Timeout) * time.Second
+		}
+		switch m.Type {
+		case "http":
+			checkers = append(checkers, NewHTTPChecker(m, timeout))
+		case "tcp":
+			checkers = append(checkers, NewTCPChecker(m, timeout))
+		case "tls":
+			checkers = append(checkers, NewTLSChecker(m, timeout))
+		case "dns":
+			checkers = append(checkers, NewDNSChecker(m, timeout))
+		default:
+			return nil, fmt.Errorf("unknown monitor type %q for %q", m.Type, m.Name)
+		}
+	}
+	return checkers, nil
+}
+
+// applyThreshold marks a successful result as failed if response time exceeds max.
+func applyThreshold(r *Result, maxResponseMS int64) {
+	if maxResponseMS > 0 && r.Up && r.ResponseTime.Milliseconds() > maxResponseMS {
+		r.Up = false
+		r.Error = fmt.Sprintf("response time %dms exceeded threshold %dms",
+			r.ResponseTime.Milliseconds(), maxResponseMS)
+	}
+}