Actions11
Overview
The node provides functionality to interact with Ethereum Virtual Machine (EVM) compatible blockchains. Specifically, the Sign Message operation allows users to cryptographically sign arbitrary messages using a private key from an EVM wallet. This is useful for proving ownership of an address or authorizing off-chain actions without sending a blockchain transaction.
Common scenarios include:
- Authenticating users by signing challenge messages.
- Creating verifiable signatures for off-chain agreements.
- Integrating with dApps that require signed messages for login or authorization.
Example: Signing a message "Hello, n8n!" with a private key to produce a signature that can be verified on-chain or by other parties.
Properties
| Name | Meaning |
|---|---|
| Wallet Source | Choose which wallet to use for signing the message: - Credential Wallet: Use the wallet configured in the node's credentials. - Input Private Key: Provide a private key directly for this signing operation. |
| Private Key | The private key string used for signing when "Input Private Key" is selected as Wallet Source. It accepts keys with or without the 0x prefix. This field is required if using custom key input. |
| Message | The text message to be signed. This is the content that will be cryptographically signed by the wallet's private key. This field is required. |
Output
The output JSON contains the result of the signing operation. Typically, it includes:
signature: The hexadecimal string representing the signed message signature.
This signature can be used externally to verify the authenticity and integrity of the signed message.
The node does not output binary data for this operation.
Dependencies
- Requires an API connection to an EVM-compatible blockchain node via RPC URL, provided through node credentials.
- Uses an API key credential for authentication to the blockchain provider.
- Depends on the
etherslibrary for wallet management and cryptographic signing. - No additional external services are required specifically for signing messages.
Troubleshooting
- Invalid private key error: If the provided private key is malformed or incorrect, the node throws an error indicating an invalid private key. Ensure the key is correctly formatted, optionally prefixed with
0x. - Missing message: The message property is required; leaving it empty will cause the node to fail.
- RPC connection issues: Although signing is done locally, some operations require RPC access. Ensure the RPC URL and credentials are correctly configured.
- Wallet source selection: Selecting "Input Private Key" requires providing a valid private key; otherwise, the node defaults to the credential wallet.