Signal CLI REST API Piece

This piece allows you to interact with Signal Messenger via the signal-cli-rest-api.

Features

Actions

• Send Message - Send text messages, attachments, stickers, reactions, and more
• Remote Delete Message - Delete messages remotely
• Create Group - Create new Signal groups
• List Groups - List all groups for a registered number
• Get Group - Get details of a specific group
• Update Group - Update group settings
• Delete Group - Delete a group
• Add/Remove Members - Manage group members
• Add/Remove Admins - Manage group administrators
• Join/Quit/Block Group - Group membership actions
• List Contacts - List all contacts
• Get Contact - Get contact details
• Update Contact - Update or add contacts
• Sync Contacts - Sync contacts to linked devices
• Update Profile - Update your Signal profile
• Send/Remove Reaction - React to messages
• Send Receipt - Send read/viewed receipts
• Start/Stop Typing - Show/hide typing indicator
• List Accounts - List all registered accounts
• Get QR Code Link - Generate QR code for device linking
• List/Add/Remove Devices - Manage linked devices
• List Attachments - List downloaded attachments
• Search Numbers - Check if numbers are registered
• List Identities - List identities for a number
• Update Account Settings - Update account settings

Triggers

• New Message Received - Trigger when a new message is received (polling-based)

Setup

1. Make sure you have signal-cli-rest-api running (e.g., via Docker)
2. Create a connection in Activepieces:
   • API Base URL: Base URL of your signal-cli-rest-api instance (default: http://localhost:8080)
   • Use HTTP Basic Auth: Enable if your API is behind a reverse proxy with HTTP Basic Auth
   • Basic Auth Username/Password: Credentials if Basic Auth is enabled
   • Default Phone Number (Optional): Default Signal phone number for this connection
3. Register or link your Signal number using the API

Connection Concept

You can create multiple connections for different purposes:

• Different Signal phone numbers
• Different API instances (e.g., different servers)
• Different authentication setups (with/without Basic Auth)

Each connection stores its own API base URL, authentication credentials, and optional default phone number. When using actions, you can select which connection to use, or the phone number can be specified per action (or use the connection's default).

Example Flows

Send a Message

1. Use the "Send Message" action
2. Enter your registered phone number
3. Add recipients (phone numbers or group IDs)
4. Enter your message
5. Optionally add attachments, reactions, or other features

Receive Messages

1. Use the "New Message Received" trigger
2. Configure your phone number and polling settings
3. The trigger will fire when new messages arrive

Manage Groups

1. Use "List Groups" to see all your groups
2. Use "Create Group" to create a new group
3. Use "Add Members to Group" to add members
4. Use "Update Group" to change group settings

Notes

• Phone numbers must be in international format (e.g., +43123456789)
• Group IDs are base64-encoded strings
• Attachments must be base64-encoded
• The receive trigger uses polling (works in normal/native mode)