go-ethereum/xeth/whisper.go

92 lines
2.8 KiB
Go

// Contains the external API to the whisper sub-protocol.
package xeth
import (
"fmt"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/logger"
"github.com/ethereum/go-ethereum/whisper"
)
var qlogger = logger.NewLogger("XSHH")
// Whisper represents the API wrapper around the internal whisper implementation.
type Whisper struct {
*whisper.Whisper
}
// NewWhisper wraps an internal whisper client into an external API version.
func NewWhisper(w *whisper.Whisper) *Whisper {
return &Whisper{w}
}
// NewIdentity generates a new cryptographic identity for the client, and injects
// it into the known identities for message decryption.
func (self *Whisper) NewIdentity() string {
identity := self.Whisper.NewIdentity()
return common.ToHex(crypto.FromECDSAPub(&identity.PublicKey))
}
// HasIdentity checks if the the whisper node is configured with the private key
// of the specified public pair.
func (self *Whisper) HasIdentity(key string) bool {
return self.Whisper.HasIdentity(crypto.ToECDSAPub(common.FromHex(key)))
}
// Post injects a message into the whisper network for distribution.
func (self *Whisper) Post(payload string, to, from string, topics []string, priority, ttl uint32) error {
// Construct the whisper message and transmission options
message := whisper.NewMessage(common.FromHex(payload))
options := whisper.Options{
To: crypto.ToECDSAPub(common.FromHex(to)),
TTL: time.Duration(ttl) * time.Second,
Topics: whisper.NewTopicsFromStrings(topics...),
}
if len(from) != 0 {
if key := self.Whisper.GetIdentity(crypto.ToECDSAPub(common.FromHex(from))); key != nil {
options.From = key
} else {
return fmt.Errorf("unknown identity to send from: %s", from)
}
}
// Wrap and send the message
pow := time.Duration(priority) * time.Millisecond
envelope, err := message.Wrap(pow, options)
if err != nil {
return err
}
if err := self.Whisper.Send(envelope); err != nil {
return err
}
return nil
}
// Watch installs a new message handler to run in case a matching packet arrives
// from the whisper network.
func (self *Whisper) Watch(to, from string, topics [][]string, fn func(WhisperMessage)) int {
filter := whisper.Filter{
To: crypto.ToECDSAPub(common.FromHex(to)),
From: crypto.ToECDSAPub(common.FromHex(from)),
Topics: whisper.NewFilterTopicsFromStrings(topics...),
}
filter.Fn = func(message *whisper.Message) {
fn(NewWhisperMessage(message))
}
return self.Whisper.Watch(filter)
}
// Messages retrieves all the currently pooled messages matching a filter id.
func (self *Whisper) Messages(id int) []WhisperMessage {
pool := self.Whisper.Messages(id)
messages := make([]WhisperMessage, len(pool))
for i, message := range pool {
messages[i] = NewWhisperMessage(message)
}
return messages
}