NostrSharp 1.0.0

NostrSharp

A library that provide a set of tools for Nostr developement

Preview

This library is inspired by this repo. You can freely use NostrSharp in any kind of projects you want.

IMPORTANT! This library is not yet tested enough for a production environment. Feel free to try it, send feedback and contribute.

This library is meant to provide necessary tools to build your own nostr-based software It's usable both on desktop/mobile and web environments.

I've implemented all kinds of events detailed in the Nostr repository, HOWEVER i didn't yet tested most of the implementations i made, so be careful.

Some of the things i tested:

• multiple relays connection
• obtaining relays NIP-11 information document
• requesting events with filters
• NPub and NSec generation
• keys conversions between hex and bech32
• events signing
• events serialization/deserialization
• publishing events to multiple relays

How to use it

The easiest way in my opinion is to rely entirely on the NSMain class, however, since the vast majority of the library's classes and methods are public you are not forced to.

NSMain ns = new NSMain();

// Initialize it by giving at least one of NPub or NSec
ns.Init(nPub, nSec);

// Connect to a list of relays by they uris
await ns.ConnectRelays(relaysUriList);
// Add a new relay in any moment
ns.AddRelay(relayUri);
// Remove a relay in any moment
await ns.DisconnectRelay(relayUri);

// Asking to all connected relays all my Kind 1 events (uses previously given NPub)
await ns.GetMyShortTextNotes();

// Don't forget to dispose
ns.Dispose();

When you want to create and fill a new event you could use the static class NSEventMaker. This class contains a comprehensive collection of helper methods to help you generate the NEvent you want.

For example, to create a ready-to-sign event for a short text note you could write the following:

NEvent ev = NSEventMaker.ShortTextNote("Hello World! This is my first note!");

The resulting NEvent is the instance you need to sign and then broadcast to relays:

// If the signing procedure goes well
if (ev.Sign(nSec))
{
    // I can broadcast the event to all my connected relays
    await ns.SendEvent(ev);

    // Or maybe to just one
    await ns.SendEvent(specificRelayUri, ev);
}

Whenever i'm requesting a filtered set of events, or broadcasting a new one, i will always need to listen for result events:

// If i want to listen for all Kind 1 events i receive from relays i have to subscribe to this event
ns.OnShortTextNote += OnShortTextNote;

void OnShortTextNote(Uri relayUri, NEvent receivedShortTextNoteEvent)
{
    // I receive the uri of the relay that has sent the event, and the deserialized event itself
}

// If i want to know if an event i broadcasted is approved or refused
ns.OnEventApproved += OnEventApproved;
ns.OnEventRefused += OnEventRefused;

void OnEventApproved(Uri relayUri, string eventId, string message)
{
    // I receive the uri of the responding relay, the id of the event i tried to broadcast
    // and an optional error message from the relay describing the operation
}
void OnEventRefused(Uri relayUri, string eventId, string message)
{
    // I receive the uri of the responding relay, the id of the event i tried to broadcast
    // and an optional text message from the relay describing the operation
}

Other Stuff

Keys

You can generate a new key pair

NSKeyPair kp = NSKeyPair.GenerateNew();

You can import an existing key from both Hex or Bech32 formats, and then have it on the other format

NSec nsec1 = NSec.FromBech32("bech32_nsec_string");
string hex = nsec1.Hex;

NSec nsec2 = NSec.FromHex("hex_nsec_string");
string bech32 = nsec2.Bech32;

Utilities

You can verify NIP05:

NIP05? checkedNIP05 = await NSUtilities.CheckNIP05(nPubHexToCheck, nip05String);
if (checkedNIP05 is not null)
{
    // Valid NIP-05
}

When you need to parse the event content to get all embedded references to events or profiles, you can use EventContentParser

// This return a list of all the identifiers found inside the event's content
List<NostrIdentifier> identifiers = EventContentParser.ParseEventContent(eventToBeParsed);