feat: add option to restart monitoring after event download in AchSession

bridges/ach_server.py

@@ -139,6 +139,7 @@ class AchSession:
         state_path: Path,
         db: "SeismoDb",
         clear_after_download: bool = False,
+        restart_monitoring: bool = False,
     ) -> None:
         self.sock                 = sock
         self.peer                 = peer
@@ -149,6 +150,7 @@ class AchSession:
         self.state_path           = state_path
         self.db                   = db
         self.clear_after_download = clear_after_download
+        self.restart_monitoring   = restart_monitoring
 
     def run(self) -> None:
         ts = datetime.datetime.now().strftime("%Y%m%d_%H%M%S")
@@ -319,6 +321,38 @@ class AchSession:
                         "peer":              self.peer,
                     }
                     _save_state(self.state_path, state)
+
+                    # ── Erase even when no new events (if requested) ──────────
+                    # Blastware ACH always erases after every session — even when
+                    # nothing new was downloaded.  Without the erase the device
+                    # still sees stored events in its memory and immediately
+                    # retries the call-home, causing the looping we observed.
+                    # Only erase when device actually has events stored; skip
+                    # the erase if device_keys is empty (nothing to erase).
+                    if self.clear_after_download and device_keys:
+                        log.info(
+                            "  Clearing device memory (--clear-after-download, "
+                            "no new events but device has %d stored)...",
+                            len(device_keys),
+                        )
+                        try:
+                            client.delete_all_events()
+                            log.info("  [OK] Device memory cleared")
+                            # Reset state so the next session starts fresh.
+                            state[unit_key] = {
+                                "downloaded_keys":    [],
+                                "max_downloaded_key": "00000000",
+                                "last_seen":          datetime.datetime.now().isoformat(),
+                                "serial":             serial,
+                                "peer":               self.peer,
+                            }
+                            _save_state(self.state_path, state)
+                        except Exception as exc:
+                            log.error(
+                                "  [WARN] Event deletion failed: %s -- events NOT cleared",
+                                exc,
+                            )
+
                     log.info("Session complete (no new events) -> %s", session_dir)
                     return
             else:
@@ -489,6 +523,15 @@ class AchSession:
             except Exception as exc:
                 log.error("  [FAIL] Event download failed: %s", exc, exc_info=True)
 
+            # ── Optional: restart monitoring after successful download ─────────
+            if self.restart_monitoring:
+                log.info("  Restarting monitoring on device (--restart-monitoring)...")
+                try:
+                    client.start_monitoring()
+                    log.info("  [OK] Monitoring restarted")
+                except Exception as exc:
+                    log.warning("  [WARN] Failed to restart monitoring: %s", exc)
+
         finally:
             raw_fh.close()
             client.close()  # closes transport / socket cleanly
@@ -593,6 +636,7 @@ def serve(args: argparse.Namespace) -> None:
     print(f"  State file: {state_path}")
     print(f"  Max events per session: {max_ev if max_ev else 'unlimited'}")
     print(f"  Clear device after download: {'YES' if args.clear_after_download else 'no'}")
+    print(f"  Restart monitoring after download: {'YES' if args.restart_monitoring else 'no'}")
     print(f"{'='*60}")
     print(f"\n  Point your test unit's ACEmanager call-home settings to:")
     print(f"    Remote Host: <this machine's LAN IP>")
@@ -631,6 +675,7 @@ def serve(args: argparse.Namespace) -> None:
                     state_path=state_path,
                     db=db,
                     clear_after_download=args.clear_after_download,
+                    restart_monitoring=args.restart_monitoring,
                 )
                 t = threading.Thread(target=session.run, daemon=True, name=f"ach-{peer}")
                 t.start()
@@ -694,6 +739,16 @@ def parse_args() -> argparse.Namespace:
             "If not specified, all IPs are accepted (not recommended for public servers)."
         ),
     )
+    p.add_argument(
+        "--restart-monitoring",
+        action="store_true",
+        default=False,
+        help=(
+            "After downloading events, send SUB 0x96 (start monitoring) before "
+            "disconnecting. Required for RV55 units whose firmware does not assert "
+            "DCD on disconnect — without this the unit stays idle after a call-home."
+        ),
+    )
     p.add_argument(
         "--clear-after-download",
         action="store_true",