Browser Session Monitor Implementation Summary

browser-session-monitor-summary.md

Browser Session Monitor Implementation Summary

Problem

The container-side idle detection (--destroy-after-idle-ms) was ineffective because the daemon maintains a persistent CDP connection with keepalives. The cdp-activity-monitor.sh watched all CDP packets via tcpdump, but the constant keepalive traffic prevented idle detection from ever triggering.

Solution

Move idle detection to the host side by:

1. Having the wrapper script touch activity files on every invocation
2. A new monitor command checks activity file mtime to detect idle sessions
3. When idle, the monitor closes sessions via the wrapper's close command

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Files Changed

New Files

clis/internalctl/internalctl/run_monitor_browser_sessions.py

New command implementation that:

• Lists *.activity files in ~/.local/share/agent-browser/
• Checks each activity file's mtime to determine idle time
• Closes sessions that exceed the idle threshold
• Supports --idle-timeout, --check-interval, --dry-run, and --once options

Modified Files

system/arthack/.local/bin/arthack-agent-browser

The wrapper script now:

• Creates STATE_DIR=~/.local/share/agent-browser on startup
• Touches ${session_name}.activity on every invocation
• Writes ${session_name}.container when starting a new browser (maps session to container name)
• Handles close command specially: closes daemon, stops container, cleans up state files
• No longer passes --destroy-after-idle-ms to browserctl

clis/internalctl/internalctl/cli.py

Added monitor-browser-sessions command with options:

• --idle-timeout SECONDS (default: 90)
• --check-interval SECONDS (default: 15)
• --dry-run - show what would happen
• --once - run once and exit (for testing)

clis/browserctl/browserctl/cli.py

Removed --destroy-after-idle-ms option from start-browser command.

clis/browserctl/browserctl/run_start_browser.py

• Removed DESTROY_AFTER_IDLE_MS environment variable handling
• Removed destroy_after_idle_ms from saved state

clis/browserctl/browserctl/run_show_browser.py

• Removed destroy_after_idle_ms display logic from verbose mode
• Simplified idle info display

clis/browserctl/browserctl/run_list_browsers.py

• Removed destroy_after_idle_ms display logic from verbose mode
• Simplified idle info display

clis/browserctl/container/Containerfile

• Removed tcpdump from installed packages (was only used for CDP monitoring)
• Removed COPY commands for cdp-activity-monitor.sh and idle-reporter.sh
• Removed chmod for deleted scripts

clis/internalctl/internalctl/x_browser.py

• Removed --destroy-after-idle-ms 30000 from browserctl start command
• Existing close_browser() function handles cleanup

clis/scrapectl/scrapectl/helpers.py

• Removed DESTROY_AFTER_IDLE_MS constant
• Removed --destroy-after-idle-ms from browserctl start command
• Added new close_browser() function for explicit cleanup

Deleted Files

• clis/browserctl/container/scripts/cdp-activity-monitor.sh - Watched CDP traffic via tcpdump
• clis/browserctl/container/scripts/idle-reporter.sh - Checked activity file mtime and killed supervisord when idle
• clis/browserctl/container/services/cdp-activity.conf - Supervisor config for cdp-activity-monitor
• clis/browserctl/container/services/idle-reporter.conf - Supervisor config for idle-reporter

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Usage

Start the monitor (typically in a background service)

internalctl monitor-browser-sessions

With custom settings

internalctl monitor-browser-sessions --idle-timeout 60 --check-interval 10

Test mode (run once)

internalctl monitor-browser-sessions --once --dry-run

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Flow

1. Agent calls: arthack-agent-browser --session myname goto https://example.com
2. Wrapper touches ~/.local/share/agent-browser/myname.activity
3. Wrapper writes container name to ~/.local/share/agent-browser/myname.container (on first start)
4. Monitor loop checks mtime of *.activity files
5. If (now - mtime) >= idle_timeout:
   - Runs: arthack-agent-browser close --session myname
   - Wrapper closes daemon, stops container, removes state files

---

Commits

1. refactor(browserctl): remove container-side idle detection

   • Removes --destroy-after-idle-ms option
   • Deletes container scripts and supervisor configs
   • Updates all callers

2. feat(internalctl): add host-side browser session monitor

   • Adds monitor-browser-sessions command
   • Updates wrapper with activity tracking and close handling