Initial structure

internal/checks/tcp.go

@@ -0,0 +1,22 @@
+package checks
+
+import (
+	"context"
+	"net"
+	"time"
+
+	"github.com/jasper/quptime/internal/config"
+)
+
+type tcpProber struct{}
+
+func (tcpProber) Probe(ctx context.Context, c *config.Check) Result {
+	start := time.Now()
+	d := net.Dialer{Timeout: c.Timeout}
+	conn, err := d.DialContext(ctx, "tcp", c.Target)
+	if err != nil {
+		return Result{OK: false, Detail: err.Error(), Latency: time.Since(start)}
+	}
+	_ = conn.Close()
+	return Result{OK: true, Latency: time.Since(start)}
+}