feat: soporte Android/Termux — battery_file + log_file (file-IPC sin exec), tail de logcat, workarounds DNS(1.1.1.1)+CA(SSL_CERT_FILE), procesos Android-safe

main.go

@@ -18,6 +18,7 @@ import (
 	"context"
 	"flag"
 	"log"
+	"net"
 	"os"
 	"os/signal"
 	"syscall"
@@ -26,11 +27,45 @@ import (
 	"fn-registry/functions/infra"
 )
 
+// androidWorkarounds fixes two things that break a standard cross-compiled Go
+// binary on Android/Termux (no-op on Linux servers):
+//   - DNS: the pure-Go resolver reads /etc/resolv.conf, which on Android does
+//     not reflect the system DNS, so lookups hit ::1:53 and fail. We point the
+//     default resolver at a public DNS server explicitly.
+//   - TLS: Go's default CA bundle paths don't exist on Android, so HTTPS fails
+//     with "certificate signed by unknown authority". We point SSL_CERT_FILE at
+//     the Termux ca-certificates bundle (read lazily by crypto/x509 on first use).
+func androidWorkarounds() {
+	if os.Getenv("ANDROID_ROOT") == "" && os.Getenv("ANDROID_DATA") == "" {
+		return
+	}
+	net.DefaultResolver = &net.Resolver{
+		PreferGo: true,
+		Dial: func(ctx context.Context, network, address string) (net.Conn, error) {
+			d := net.Dialer{Timeout: 5 * time.Second}
+			return d.DialContext(ctx, "udp", "1.1.1.1:53")
+		},
+	}
+	if os.Getenv("SSL_CERT_FILE") == "" {
+		prefix := os.Getenv("PREFIX")
+		if prefix == "" {
+			prefix = "/data/data/com.termux/files/usr"
+		}
+		cert := prefix + "/etc/tls/cert.pem"
+		if _, err := os.Stat(cert); err == nil {
+			os.Setenv("SSL_CERT_FILE", cert)
+		}
+	}
+	log.Print("android: using 1.1.1.1 resolver + Termux CA bundle")
+}
+
 func main() {
 	configPath := flag.String("config", "", "path to JSON config file")
 	once := flag.Bool("once", false, "collect and push a single time, then exit (useful for testing)")
 	flag.Parse()
 
+	androidWorkarounds()
+
 	cfg, err := loadConfig(*configPath)
 	if err != nil {
 		log.Fatalf("config: %v", err)
@@ -58,9 +93,10 @@ func main() {
 		cancel()
 	}()
 
-	// Optional: ship systemd journal logs to Loki in the background.
+	// Optional: ship logs to Loki in the background (journald on Linux,
+	// logcat on Android/Termux).
 	if cfg.LokiURL != "" {
-		go shipJournald(ctx, cfg)
+		go shipLogs(ctx, cfg)
 	}
 
 	ticker := time.NewTicker(time.Duration(cfg.IntervalSec) * time.Second)
@@ -89,6 +125,10 @@ func pushOnce(cfg Config) error {
 	if err != nil {
 		return err
 	}
+	// Battery metrics are best-effort. On Android/Termux the agent cannot exec
+	// termux-battery-status (seccomp), so a shell helper writes its JSON to
+	// cfg.BatteryFile and we parse that here; elsewhere we collect directly.
+	samples = append(samples, batterySamples(cfg)...)
 	body := infra.FormatPromExposition(samples, time.Now().UnixMilli())
 	if err := infra.PushPromRemote(cfg.HubURL, cfg.User, cfg.Pass, body, map[string]string{"instance": cfg.Node}); err != nil {
 		return err
@@ -96,3 +136,25 @@ func pushOnce(cfg Config) error {
 	log.Printf("pushed %d samples", len(samples))
 	return nil
 }
+
+// batterySamples returns battery metrics, reading them from a JSON file when
+// cfg.BatteryFile is set (Android path) or collecting them directly otherwise.
+// Always best-effort: any error yields no samples rather than failing the push.
+func batterySamples(cfg Config) []infra.PromSample {
+	if cfg.BatteryFile != "" {
+		data, err := os.ReadFile(cfg.BatteryFile)
+		if err != nil {
+			return nil
+		}
+		s, err := infra.BatterySamplesFromJSON(data)
+		if err != nil {
+			return nil
+		}
+		return s
+	}
+	s, err := infra.CollectBatteryMetrics()
+	if err != nil {
+		return nil
+	}
+	return s
+}