well-goknown/vendor/github.com/nbd-wtf/go-nostr/event.go
2024-11-11 14:56:01 -05:00

84 lines
1.7 KiB
Go

package nostr
import (
"crypto/sha256"
"encoding/hex"
"fmt"
"github.com/mailru/easyjson"
)
type Event struct {
ID string
PubKey string
CreatedAt Timestamp
Kind int
Tags Tags
Content string
Sig string
// anything here will be mashed together with the main event object when serializing
extra map[string]any
}
// Event Stringer interface, just returns the raw JSON as a string.
func (evt Event) String() string {
j, _ := easyjson.Marshal(evt)
return string(j)
}
// GetID serializes and returns the event ID as a string.
func (evt *Event) GetID() string {
h := sha256.Sum256(evt.Serialize())
return hex.EncodeToString(h[:])
}
// CheckID checks if the implied ID matches the given ID
func (evt *Event) CheckID() bool {
ser := evt.Serialize()
h := sha256.Sum256(ser)
const hextable = "0123456789abcdef"
for i := 0; i < 32; i++ {
b := hextable[h[i]>>4]
if b != evt.ID[i*2] {
return false
}
b = hextable[h[i]&0x0f]
if b != evt.ID[i*2+1] {
return false
}
}
return true
}
// Serialize outputs a byte array that can be hashed/signed to identify/authenticate.
// JSON encoding as defined in RFC4627.
func (evt *Event) Serialize() []byte {
// the serialization process is just putting everything into a JSON array
// so the order is kept. See NIP-01
dst := make([]byte, 0)
// the header portion is easy to serialize
// [0,"pubkey",created_at,kind,[
dst = append(dst, []byte(
fmt.Sprintf(
"[0,\"%s\",%d,%d,",
evt.PubKey,
evt.CreatedAt,
evt.Kind,
))...)
// tags
dst = evt.Tags.marshalTo(dst)
dst = append(dst, ',')
// content needs to be escaped in general as it is user generated.
dst = escapeString(dst, evt.Content)
dst = append(dst, ']')
return dst
}