From e2f088286fcd324bb4754dcdf5ff10f4dc823b5b Mon Sep 17 00:00:00 2001 From: Semisol <45574030+Semisol@users.noreply.github.com> Date: Thu, 30 Mar 2023 00:35:13 +0300 Subject: [PATCH] NIP-47 Wallet Connect --- 47.md | 112 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 112 insertions(+) create mode 100644 47.md diff --git a/47.md b/47.md new file mode 100644 index 00000000..326100de --- /dev/null +++ b/47.md @@ -0,0 +1,112 @@ +NIP-47 +====== + +Nostr Wallet Connect +-------------------- + +`draft` `optional` `author:kiwiidb` `author:bumi` `author:semisol` `author:vitorpamplona` + +## Rationale + +Paying zaps should be possible without the user needing to open a different app to only pay a Lightning invoice. +This NIP describes a way for users to control a remote Lightning node or a custodial Lightning wallet. When self-hosting, this setup does not require the user to run their own server, thereby bypassing certain hurdles that are commonly encountered when trying to connect to a Lightning node remotely. + +## Terms + +* **client**: Nostr app on any platform that wants to pay Lightning invoices +* **wallet service**: Nostr app that typically runs on an always-on computer (eg. in the cloud or on a Raspberry Pi). + +## Events + +There are two event kinds: +- `NIP-47 request`: 23194 +- `NIP-47 response`: 23195 + +Both the request and response events SHOULD only contain one `p` tag, containing the public key of the **wallet service** if this is a request, and the public key of the **client** if this is a response. + +The content is encrypted with [NIP04](https://github.com/nostr-protocol/nips/blob/master/04.md), and is a JSON object. The content depends on the kind. + +Request: +```jsonc +{ + "cmd": "pay_invoice", // command, string + "data": { // data, object + "invoice": "lnbc50n1..." // command-related data + } +} +``` + +Response: +```jsonc +{ + "status": "ok", // status, "ok" | "error" + "event": "0123456789abcdef...", // event the command is in response to, string + "data": { // response data + "preimage": "0123456789abcdef..." // command-related data + } +} +``` + +The data field SHOULD contain a `message` field with a human readable error message if the status is `error`. + +## Nostr Wallet Connect URI +**client** discovers **wallet service** by scanning a QR code, handling a deeplink or pasting in a URI. + +The **wallet service** generates this connection URI with protocol `nostr+walletconnect:` and base path it's hex-encoded `pubkey` with the following query string parameters: + +- `relay` Required. URL of the relay where the **wallet service** is connected and will be listening for events. May be more than one. +- `secret` Required. 32-byte randomly generated hex encoded string. The **client** should use this to sign events when communicating with the **wallet service**. + - Authorization does not require passing keys back and forth. + - The user can have different keys for different applications. Keys can be revoked and created at will and have arbitrary constraints (eg. budgets). + - The key is harder to leak since it is not shown to the user and backed up. + - It improves privacy because the user's main key would not be linked to their payments. + +The **client** should then store this connection and use it when the user wants to perform actions like paying an invoice. Optionally it can display metadata about the connected **wallet service** from it's profile (name, image, url). + +### Example connection string +```sh +nostrwalletconnect:b889ff5b1513b641e2a139f661a661364979c5beee91842f8f0ef42ab558e9d4?relay=wss%3A%2F%2Frelay.damus.io&secret=71a8c14c1407c113601079c4302dab36460f0ccd0ad506f1f2dc73b5100e4f3c +``` + +## Commands + +### `pay_invoice` + +Description: Requests payment of an invoice. + +Request: +```jsonc +{ + "invoice": "lnbc50n1..." // BOLT11 invoice, string +} +``` + +Response: +```jsonc +{ + "preimage": "0123456789abcdef..." // preimage after payment, string +} +``` + +### `balance` + +Description: Requests the balance of the wallet. + +Request: an empty JSON object. + +Response: +```jsonc +{ + "balance": 100000 // balance in msat, int +} +``` + +## Example pay invoice flow + +0. The user scans the QR code generated by the **wallet service** with their **client** application, they follow a `nostrwalletconnect:` deeplink or configure the connection details manually. +1. **client** sends an event to with **wallet service** service with kind `23194`. The content is a `pay_invoice` request. The private key is the secret from the connection string above. +2. **nostr-wallet-connect-service** verifies that the author's key is authorized to perform the payment, decrypts the payload and sends the payment. +3. **nostr-wallet-connect-service** responds to the event by sending an event with kind `23195` and content being a response either containing an error message or a preimage. + +## Using a dedicated relay +This NIP does not specify any requirements on the type of relays used. However, if the user is using a custodial service it might make sense to use a relay that is hosted by the custodial service. The relay may then enforce authentication to prevent metadata leaks. Not depending on a 3rd party relay would also improve reliability in this case.