go-nostr
========
A set of useful things for [Nostr Protocol](https://github.com/nostr-protocol/nostr) implementations.
[](https://github.com/nbd-wtf/go-nostr/actions/workflows/test.yml)
Install go-nostr:
```bash
go get github.com/nbd-wtf/go-nostr
```
### Generating a key
``` go
package main
import (
"fmt"
"github.com/nbd-wtf/go-nostr"
"github.com/nbd-wtf/go-nostr/nip19"
)
func main() {
sk := nostr.GeneratePrivateKey()
pk, _ := nostr.GetPublicKey(sk)
nsec, _ := nip19.EncodePrivateKey(sk)
npub, _ := nip19.EncodePublicKey(pk)
fmt.Println("sk:", sk)
fmt.Println("pk:", pk)
fmt.Println(nsec)
fmt.Println(npub)
}
```
### Subscribing to a single relay
``` go
ctx := context.Background()
relay, err := nostr.RelayConnect(ctx, "wss://nostr.zebedee.cloud")
if err != nil {
panic(err)
}
npub := "npub1422a7ws4yul24p0pf7cacn7cghqkutdnm35z075vy68ggqpqjcyswn8ekc"
var filters nostr.Filters
if _, v, err := nip19.Decode(npub); err == nil {
pub := v.(string)
filters = []nostr.Filter{{
Kinds: []int{nostr.KindTextNote},
Authors: []string{pub},
Limit: 1,
}}
} else {
panic(err)
}
ctx, cancel := context.WithTimeout(ctx, 3*time.Second)
defer cancel()
sub, err := relay.Subscribe(ctx, filters)
if err != nil {
panic(err)
}
for ev := range sub.Events {
// handle returned event.
// channel will stay open until the ctx is cancelled (in this case, context timeout)
fmt.Println(ev.ID)
}
```
### Publishing to two relays
``` go
sk := nostr.GeneratePrivateKey()
pub, _ := nostr.GetPublicKey(sk)
ev := nostr.Event{
PubKey: pub,
CreatedAt: nostr.Now(),
Kind: nostr.KindTextNote,
Tags: nil,
Content: "Hello World!",
}
// calling Sign sets the event ID field and the event Sig field
ev.Sign(sk)
// publish the event to two relays
ctx := context.Background()
for _, url := range []string{"wss://nostr.zebedee.cloud", "wss://nostr-pub.wellorder.net"} {
relay, err := nostr.RelayConnect(ctx, url)
if err != nil {
fmt.Println(err)
continue
}
_, err = relay.Publish(ctx, ev)
if err != nil {
fmt.Println(err)
continue
}
fmt.Printf("published to %s\n", url)
}
```
### Authenticating with NIP-42
For this section, the user needs access to a relay implementing NIP-42.
E.g., https://github.com/fiatjaf/relayer with a relay implementing the relayer.Auther interface.
``` go
func main() {
url := "ws://localhost:7447"
sk := nostr.GeneratePrivateKey()
relay, err := nostr.RelayConnect(context.Background(), url,
nostr.WithAuthHandler(func(ctx context.Context, authEvent *Event) (ok bool) {
authEvent.Sign(sk)
}),
)
if err != nil {
panic(err)
}
}
```
### Example script
```
go run example/example.go
```