A simple CLI interface for offline signing. This can also be executed via the docker image.
To create a transaction, you need to use the API to connect to a chain, enabling the creation of a transaction using the chain's metadata. In a terminal, run the submit command with the following form:
yarn run:signer submit --account <ss58> --ws <endpoint> <module.method> [param1] [...] [paramX]
For instance, to make a transfer, we run the following command:
yarn run:signer submit --account 5HNHXTw65dTNVGRdYkxFUpKcvmUYQMZHcDHmSKpuC8pvVEaN --ws wss://poc3-rpc.polkadot.io/ balances.transfer 5DkQbYAExs3M2sZgT1Ec3mKfZnAQCL4Dt9beTCknkCUn5jzo 123
On execution, it will prompt us with:
Payload: 0x040300ff4a83f1...a8239139ff3ff7c3f6
Signature>
The Payload is the hex that needs to be signed. Pasting the hex signature (followed by Enter) submits it to the chain.
You can also use this command to submit pre-signed transactions, e.g. generated using the sendOffline command (see below).
The syntax is as follows:
yarn run:signer submit --tx <signedTransaction> --ws <endpoint>
To sign, you do not need a network connection at all and this command does not use the API to make connections to a chain. In a terminal, run the sign command with the following form:
yarn run:signer sign --account <ss58> --seed <suri> --type <ed25519|sr25519> <hex payload>
For instance, to sign the transfer made above, we run:
yarn run:signer sign --account 5HNHXTw65dTNVGRdYkxFUpKcvmUYQMZHcDHmSKpuC8pvVEaN --seed "leaf ... rude" --type sr25519 0x040300ff4a83f1...a8239139ff3ff7c3f6
On execution, it will respond with:
Signature: 0xe6facf194a8e...413ce3155c2d1240b
Paste this signature into the submission in the first terminal, and off we go.
By default, submit will create a mortal extrinsic with a lifetime of 50 blocks. Assuming a six-second block time, you will have five minutes to go offline, sign the transaction, paste the signature, and submit the signed transaction.
This functionality lets you generate signed transactions for execution at a later time, on a different device or using other tools. It is intended to resemble MyEtherWallet's Send offline feature.
The flow is similar to the submit command. First, run the sendOffline command on a computer with a network connection:
yarn run:signer sendOffline --account 5HNHXTw65dTNVGRdYkxFUpKcvmUYQMZHcDHmSKpuC8pvVEaN --ws wss://poc3-rpc.polkadot.io/ balances.transfer 5DkQbYAExs3M2sZgT1Ec3mKfZnAQCL4Dt9beTCknkCUn5jzo 123
This will give you a payload to sign. Use the sign command as per instructions above.
Once you've pasted the signature into the sendOffline terminal (and hit Enter), it will print the signed transaction that can be stored and submitted later (e.g. using the submit command).
Run yarn run:signer --help to learn about optional parameters.