When to use this skill

Use this skill when you need to:

• Develop or modify LINE Bot webhook handlers

• Implement new bot commands and message responses

• Handle LINE events (messages, join/leave groups)

• Integrate LINE Messaging API features

• Debug LINE Bot webhook issues

• Test bot functionality in LINE groups

How to use it

Core Components

1. LINE Bot SDK Setup

Use the LINE Bot SDK v3 for Python:

from linebot.v3.messaging import MessagingApi, Configuration, ApiClient from linebot.v3.webhook import WebhookHandler, MessageEvent from linebot.v3.messaging.models import PushMessageRequest, TextMessage from linebot.v3.webhooks import TextMessageContent, JoinEvent, LeaveEvent

2. Environment Configuration

Required environment variables:

• LINE_CHANNEL_ACCESS_TOKEN

• Bot access token from LINE Developers Console

• LINE_CHANNEL_SECRET

• Channel secret for webhook verification

• LINE_GROUP_ID (optional) - Comma-separated group IDs for broadcasting

3. Webhook Handler Pattern

@app.route("/callback", methods=['POST']) def callback(): signature = request.headers['X-Line-Signature'] body = request.get_data(as_text=True)

try:
    handler.handle(body, signature)
except Exception as e:
    abort(400)

return 'OK'

@handler.add(MessageEvent, message=TextMessageContent) def handle_message(event): # Process user messages pass

@handler.add(JoinEvent) def handle_join(event): # Handle bot joining a group pass

@handler.add(LeaveEvent) def handle_leave(event): # Handle bot leaving a group pass

4. Message Sending

Reply to user message

messaging_api.reply_message( ReplyMessageRequest( reply_token=event.reply_token, messages=[TextMessage(text="Response text")] ) )

Push message to group

messaging_api.push_message( PushMessageRequest( to=group_id, messages=[TextMessage(text="Broadcast message")] ) )

5. Command Pattern

Implement commands with @ prefix:

def handle_message(event): text = event.message.text.strip()

if text.startswith('@'):
    parts = text[1:].split()
    command = parts[0].lower()
    args = parts[1:] if len(parts) > 1 else []
    
    if command == 'help':
        # Show help
    elif command == 'schedule':
        # Show schedule
    # ... more commands

Best Practices

Group Context Awareness

• Always extract group_id from events

• Store per-group configurations separately

• Validate group permissions before operations

Error Handling

• Wrap webhook handlers in try-except blocks

• Log errors for debugging

• Send user-friendly error messages back to LINE

Message Formatting

• Use emojis to enhance UX (🗑️, 📅, 👥, etc.)

• Keep messages concise and scannable

• Use line breaks for readability

Testing

• Test commands in a dedicated LINE group

• Verify webhook signature validation

• Check response times (should be quick)

Common Patterns

Multi-Group Support

Get group ID from event

group_id = event.source.group_id if hasattr(event.source, 'group_id') else None

Load group-specific data

group_data = groups.get(group_id, {})

Scheduled Broadcasting

from apscheduler.schedulers.background import BackgroundScheduler

def send_reminder(group_id): # Get group-specific schedule # Send reminder message pass

scheduler = BackgroundScheduler() scheduler.start()

Reference Links

• LINE Developers Console

• LINE Messaging API Documentation

• LINE Bot SDK for Python