add-new-group.md

How to Create a New Group Photo Wall

This guide explains how to add an independent photo wall for a new Telegram group. Each group requires its own Bot.

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Prerequisites

• The project has been deployed at least once (./deploy.sh or npx cdk deploy)
• AWS CLI is installed and credentials are configured
• You have a Telegram account

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Step 1: Create a New Telegram Bot

1. Open Telegram and search for @BotFather
2. Send /newbot
3. Provide a Bot name (e.g. Marketing Wall Bot) and a username (e.g. marketing_wall_bot, must end in bot)
4. Save the returned Bot Token
5. Turn off Privacy Mode: BotFather → /mybots → select the Bot → Bot Settings → Group Privacy → Turn off

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Step 2: Store the Bot Token in Secrets Manager

aws secretsmanager create-secret \
  --name "telegram/bot-token/marketing" \
  --secret-string "YOUR_NEW_BOT_TOKEN" \
  --region us-west-2

The marketing suffix in telegram/bot-token/marketing is arbitrary; it just has to match the secretName you set in the next step.

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Step 3: Add the New Group to cdk.json

Edit the project root cdk.json and append a new entry to the telegramGroups array:

{
  "context": {
    "telegramGroups": [
      {
        "groupId": "demo-group",
        "chatId": "-1001234567890",
        "name": "Demo Photo Wall",
        "secretName": "telegram/bot-token/demo-group",
        "botUsername": "your_photo_wall_bot"
      },
      {
        "groupId": "marketing",
        "chatId": "-1009876543210",
        "name": "Marketing Photo Wall",
        "secretName": "telegram/bot-token/marketing",
        "botUsername": "marketing_wall_bot"
      }
    ]
  }
}

Field Reference

Field	Required	Description	Example
groupId	Yes	URL identifier for the wall; letters, digits, underscore, hyphen only	marketing
chatId	Yes	Telegram group Chat ID (negative integer); see the appendix for how to obtain it	-1009876543210
name	Yes	Title shown on the photo wall page	Marketing Photo Wall
secretName	Yes	Name in Secrets Manager that holds the Bot Token; must match Step 2	telegram/bot-token/marketing
botUsername	Yes	The Bot's @username (without @); only messages that @mention it are surfaced on the wall	marketing_wall_bot

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Step 4: Deploy

cd photo-wall && npm run build && cd ..
npx cdk deploy --require-approval never

After the deployment, the CDK output prints the new group's webhook URL:

TelegramPhotoWallStack.WebhookUrlmarketing = https://<YOUR_DOMAIN>/api/webhook/marketing

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Step 5: Register the Telegram Webhook

# Fetch the webhook verification secret
WEBHOOK_SECRET=$(aws secretsmanager get-secret-value \
  --secret-id "telegram/webhook-secret" \
  --query SecretString --output text \
  --region us-west-2)

# Fetch the new Bot Token
NEW_BOT_TOKEN=$(aws secretsmanager get-secret-value \
  --secret-id "telegram/bot-token/marketing" \
  --query SecretString --output text \
  --region us-west-2)

# Register the webhook
curl -X POST "https://api.telegram.org/bot${NEW_BOT_TOKEN}/setWebhook" \
  -H "Content-Type: application/json" \
  -d "{
    \"url\": \"https://<YOUR_DOMAIN>/api/webhook/marketing\",
    \"secret_token\": \"${WEBHOOK_SECRET}\",
    \"allowed_updates\": [\"message\"]
  }"

Replace https://<YOUR_DOMAIN> with the actual CloudFront URL emitted by CDK.

Verify the Webhook

curl -s "https://api.telegram.org/bot${NEW_BOT_TOKEN}/getWebhookInfo" | python3 -m json.tool

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Step 6: Add the Bot to the Group

1. Open the target Telegram group
2. Add member → search for @marketing_wall_bot → add
3. Send a test message in the group: @marketing_wall_bot hello

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Step 7: Open the Photo Wall

https://<YOUR_DOMAIN>/wall/marketing

If multiple groups are configured, a group switcher appears at the top of the page.

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Appendix

Get the Telegram Group Chat ID

Method 1: Via the Bot API

1. Add the Bot to the group
2. Send any message in the group
3. Run:

curl -s "https://api.telegram.org/bot${NEW_BOT_TOKEN}/getUpdates" | python3 -m json.tool

4. Locate message.chat.id in the returned JSON (group Chat IDs are negative, e.g. -1009876543210)

Method 2: Via @userinfobot

1. Add @userinfobot to the group
2. It will reply with the group's Chat ID
3. Remove it once you have the value

Remove a Group

1. Remove the entry from telegramGroups in cdk.json
2. Redeploy: npx cdk deploy
3. (Optional) Delete the Bot Token: aws secretsmanager delete-secret --secret-id "telegram/bot-token/marketing" --region us-west-2
4. (Optional) Remove the webhook: curl -X POST "https://api.telegram.org/bot${NEW_BOT_TOKEN}/deleteWebhook"

Quick Reference

Step	Command / Action
1. Create the Bot	BotFather /newbot + turn off Privacy Mode
2. Store the Token	aws secretsmanager create-secret ...
3. Update config	Edit cdk.json, append the new group
4. Deploy	npx cdk deploy
5. Register webhook	curl ... setWebhook
6. Add Bot to group	Add as a Telegram group member
7. Test	Send @bot hello in the group, open /wall/groupId