When claude code finishes the conversation, send a slack message to remind myself

finish.py

#!/usr/bin/env python3
import json
import sys
import os
import requests
from urllib.parse import quote
from datetime import datetime

# ~/.claude/settings.json
'''
{
  "permissions": {
    "allow": [
      "Bash(git push:*)",
      "Bash(git checkout:*)",
      "Bash(git add:*)",
      "Bash(grep:*)",
      "Bash(find:*)",
      "Bash(nslookup:*)",
      "Bash(aws elbv2 describe-load-balancers:*)",
      "Bash(kubectl get:*)",
      "Bash(kubectl describe:*)",
      "Bash(kubectl logs:*)",
      "Bash(curl:*)",
      "Bash(jira create:*)",
      "WebFetch(domain:docs.anthropic.com)",
      "Bash(aws logs :*)"
    ],
    "deny": []
  },
  "hooks": {
    "Notification": [
      {
        "hooks": [
          {
            "type": "command",
            "command": "/home/qsun/bins/finish.py"
          }
        ]
      }
    ],
    "Stop": [
      {
        "matcher": "",
        "hooks": [
          {
            "type": "command",
            "command": "python3 /home/qsun/bins/finish.py"
          }
        ]
      }
    ]
  }
}
'''

SLACK_WEBHOOK_URL = "https://hooks.slack.com/services/XX/YYY/ZZZ"
LOG_FILE = "/tmp/finish.log"

def log_session(project_name, last_prompt, session_id, transcript_path):
    """Log session information to persistent log file."""
    try:
        timestamp = datetime.now().isoformat()
        log_entry = {
            "timestamp": timestamp,
            "session_id": session_id,
            "project_name": project_name,
            "last_prompt": last_prompt,
            "transcript_path": transcript_path
        }
        
        with open(LOG_FILE, 'a') as f:
            f.write(json.dumps(log_entry) + '\n')
    except Exception as e:
        print(f"Error writing to log file: {e}")

def send_slack_notification(project_name, last_prompt, session_id, transcript_path):
    """Send notification to Slack when Claude Code conversation finishes."""
    
    # Read last prompt from transcript if available
    last_user_message = "No prompt available"
    if transcript_path and os.path.exists(transcript_path):
        try:
            with open(transcript_path, 'r') as f:
                lines = f.readlines()
                # Parse JSONL format and find last user message
                for line in reversed(lines):
                    line = line.strip()
                    if not line:
                        continue
                    try:
                        entry = json.loads(line)
                        # Look for user type messages
                        if (entry.get('type') == 'user' and 
                            'message' in entry and 
                            entry['message'].get('role') == 'user'):
                            content = entry['message'].get('content', '')
                            if isinstance(content, str) and content.strip():
                                last_user_message = content.strip()
                                break
                    except json.JSONDecodeError:
                        continue
        except Exception:
            pass
    
    # If last_prompt is provided, use it instead
    if last_prompt:
        last_user_message = last_prompt
    
    # Truncate long messages
    if len(last_user_message) > 200:
        last_user_message = last_user_message[:197] + "..."
    
    message = {
        "text": f"🤖 Claude Code Session Finished",
        "blocks": [
            {
                "type": "section",
                "text": {
                    "type": "mrkdwn",
                    "text": f"*Claude Code Session Finished*\n\n*Project:* `{project_name}`\n*Session ID:* `{session_id}`\n*Last Prompt:* {last_user_message}"
                }
            }
        ]
    }
    
    try:
        response = requests.post(SLACK_WEBHOOK_URL, json=message, timeout=10)
        if response.status_code == 200:
            print("Slack notification sent successfully")
        else:
            print(f"Failed to send Slack notification: {response.status_code}")
    except Exception as e:
        print(f"Error sending Slack notification: {e}")

def main():
    try:
        # Read JSON data from stdin
        input_data = json.loads(sys.stdin.read())
        
        # Extract required information
        session_id = input_data.get("session_id", "unknown")
        cwd = input_data.get("cwd", os.getcwd())
        transcript_path = input_data.get("transcript_path")
        
        # Get project name from cwd
        project_name = os.path.basename(cwd) if cwd else "unknown"
        
        # Extract last prompt if available
        last_prompt = input_data.get("last_prompt", "")
        
        # Log session to persistent file
        log_session(project_name, last_prompt, session_id, transcript_path)
        
        # Send Slack notification
        send_slack_notification(project_name, last_prompt, session_id, transcript_path)
        
        # Exit successfully
        sys.exit(0)
        
    except Exception as e:
        print(f"Hook error: {e}")
        sys.exit(1)

if __name__ == "__main__":
    main()